Biosensors

19 pages, 3996 KiB

Open AccessArticle

Peroxidase-like Nanoparticles of Noble Metals Stimulate Increasing Sensitivity of Flavocytochrome b₂-Based L-Lactate Biosensors

by Galina Gayda, Olha Demkiv, Nataliya Stasyuk, Yuriy Boretsky, Mykhailo Gonchar and Marina Nisnevitch

Biosensors 2024, 14(11), 562; https://doi.org/10.3390/bios14110562 - 20 Nov 2024

Viewed by 230

Abstract

We report the development of amperometric biosensors (ABSs) employing flavocytochrome b₂ (Fcb₂) coupled with nanoparticles (NPs) of noble metals on graphite electrode (GE) surfaces. Each NPs/GE configuration was evaluated for its ability to decompose hydrogen peroxide (H₂O [...] Read more.

We report the development of amperometric biosensors (ABSs) employing flavocytochrome b₂ (Fcb₂) coupled with nanoparticles (NPs) of noble metals on graphite electrode (GE) surfaces. Each NPs/GE configuration was evaluated for its ability to decompose hydrogen peroxide (H₂O₂), mimicking peroxidase (PO) activity. The most effective nanoPO (nPO) was selected for developing ABSs targeting L-lactate. Consequently, several Fcb₂/nPO-based ABSs with enhanced sensitivity to L-lactate were developed, demonstrating mediated ET between Fcb₂ and the GE surface. The positive effect of noble metal NPs on Fcb₂-based sensor sensitivity may be explained by the synergy between their dual roles as both PO mimetics and electron transfer mediators. Furthermore, our findings provide preliminary data that may prompt a re-evaluation of the mechanism of L-lactate oxidation in Fcb₂-mediated catalysis. Previously, it was believed that L-lactate oxidation via Fcb₂ catalysis did not produce H₂O₂, unlike catalysis via L-lactate oxidase. Our initial research revealed that the inclusion of nPO in Fcb₂-based ABSs significantly increased their sensitivity. Employing other PO mimetics in ABSs for L-lactate yielded similar results, reinforcing our hypothesis that trace amounts of H₂O₂ may be generated as a transient intermediate in this reaction. The presence of nPO enhances the L-lactate oxidation rate through H₂O₂ utilization, leading to signal amplification and heightened bioelectrode sensitivity. The proposed ABSs have been successfully tested on blood serum and fermented food samples, showing their promise for L-lactate monitoring in medicine and the food industry. Full article

(This article belongs to the Special Issue Microelectrode Array for Biomedical Applications)

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27 pages, 8324 KiB

Open AccessReview

Recent Advances in the Fabrication and Application of Electrochemical Paper-Based Analytical Devices

by Zarfashan Shahid, Kornautchaya Veenuttranon, Xianbo Lu and Jiping Chen

Biosensors 2024, 14(11), 561; https://doi.org/10.3390/bios14110561 - 20 Nov 2024

Viewed by 499

Abstract

In response to growing environmental concerns, the scientific community is increasingly incorporating green chemistry principles into modern analytical techniques. Electrochemical paper-based analytical devices (ePADs) have emerged as a sustainable and efficient alternative to conventional analytical devices, offering robust applications in point-of-care testing, personalized [...] Read more.

In response to growing environmental concerns, the scientific community is increasingly incorporating green chemistry principles into modern analytical techniques. Electrochemical paper-based analytical devices (ePADs) have emerged as a sustainable and efficient alternative to conventional analytical devices, offering robust applications in point-of-care testing, personalized healthcare, environmental monitoring, and food safety. ePADs align with green chemistry by minimizing reagent use, reducing energy consumption, and being disposable, making them ideal for eco-friendly and cost-effective analyses. Their user-friendly interface, alongside sensitive and selective detection capabilities, has driven their popularity in recent years. This review traces the evolution of ePADs from simple designs to complex multilayered structures that optimize analyte flow and improve detection. It also delves into innovative electrode fabrication methods, assessing key advantages, limitations, and modification strategies for enhanced sensitivity. Application-focused sections explore recent advancements in using ePADs for detecting diseases, monitoring environmental hazards like heavy metals and bacterial contamination, and screening contaminants in food. The integration of cutting-edge technologies, such as wearable wireless devices and the Internet of Things (IoT), further positions ePADs at the forefront of point-of-care testing (POCT). Finally, the review identifies key research gaps and proposes future directions for the field. Full article

(This article belongs to the Special Issue Paper-Based Biosensing Technologies: From Design to Application)

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29 pages, 4599 KiB

Open AccessReview

Advances in Wearable Biosensors for Healthcare: Current Trends, Applications, and Future Perspectives

by Dang-Khoa Vo and Kieu The Loan Trinh

Biosensors 2024, 14(11), 560; https://doi.org/10.3390/bios14110560 - 18 Nov 2024

Viewed by 670

Abstract

Wearable biosensors are a fast-evolving topic at the intersection of healthcare, technology, and personalized medicine. These sensors, which are frequently integrated into clothes and accessories or directly applied to the skin, provide continuous, real-time monitoring of physiological and biochemical parameters such as heart [...] Read more.

Wearable biosensors are a fast-evolving topic at the intersection of healthcare, technology, and personalized medicine. These sensors, which are frequently integrated into clothes and accessories or directly applied to the skin, provide continuous, real-time monitoring of physiological and biochemical parameters such as heart rate, glucose levels, and hydration status. Recent breakthroughs in downsizing, materials science, and wireless communication have greatly improved the functionality, comfort, and accessibility of wearable biosensors. This review examines the present status of wearable biosensor technology, with an emphasis on advances in sensor design, fabrication techniques, and data analysis algorithms. We analyze diverse applications in clinical diagnostics, chronic illness management, and fitness tracking, emphasizing their capacity to transform health monitoring and facilitate early disease diagnosis. Additionally, this review seeks to shed light on the future of wearable biosensors in healthcare and wellness by summarizing existing trends and new advancements. Full article

(This article belongs to the Special Issue Artificial Skins and Wearable Biosensors for Healthcare Monitoring)

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16 pages, 2696 KiB

Open AccessArticle

A Paper-Based Assay for the Determination of Total Antioxidant Capacity in Human Serum Samples

by Michelle T. Tran, Sophia V. Gomez, Vera Alenicheva and Vincent T. Remcho

Biosensors 2024, 14(11), 559; https://doi.org/10.3390/bios14110559 - 18 Nov 2024

Viewed by 423

Abstract

Determining the total antioxidant capacity (TAC) of biological samples is a valuable approach to measuring health status under oxidative stress conditions, such as infertility and type 2 diabetes. The Trolox equivalent antioxidant capacity (TEAC) assay is the most common approach to evaluating TAC [...] Read more.

Determining the total antioxidant capacity (TAC) of biological samples is a valuable approach to measuring health status under oxidative stress conditions, such as infertility and type 2 diabetes. The Trolox equivalent antioxidant capacity (TEAC) assay is the most common approach to evaluating TAC in biological matrices. This assay is typically performed in clinical settings on a microtiter plate using a plate reader. However, the instrumentation and expertise requirements, and the resulting delay in the reporting of assay outcomes, make solution-based TEAC assays impractical for point-of-care or at-home testing, where individuals may want to monitor their health status during treatment. This work introduces the first microfluidic paper-based analytical device (µPAD) that measures TAC in human serum using TEAC assay chemistry. TAC was determined through a colorimetric image analysis of the degree of decolorization of 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cations (ABTS^●+) by serum antioxidants. The µPAD showed a linear response to Trolox, ranging from 0.44 to 2.4 mM, (r = 0.999). The performance of paper-based TEAC assays was validated through direct comparison to solution-based TEAC assays. There was a 0.04 mM difference in TAC values between the two platforms, well within one standard deviation of a standard solution-based assay conducted on an aliquot of the same serum sample (±0.25 mM). The µPAD had a limit of detection (LOD) of 0.20 mM, well below the TAC of normal human serum. The results suggest that the proposed device can be used for biological TAC determination and expands the field of TAC analysis in point-of-care health monitoring. Full article

(This article belongs to the Section Nano- and Micro-Technologies in Biosensors)

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21 pages, 13351 KiB

Open AccessArticle

Bioluminescent Whole-Cell Bioreporter Bacterial Panel for Sustainable Screening and Discovery of Bioactive Compounds Derived from Mushrooms

by Calin Trif, Jovana Vunduk, Yardnapar Parcharoen, Aporn Bualuang and Robert S. Marks

Biosensors 2024, 14(11), 558; https://doi.org/10.3390/bios14110558 - 17 Nov 2024

Viewed by 415

Abstract

This study presents a rapid and comprehensive method for screening mushroom extracts for the putative discovery of bioactive molecules, including those exhibiting antimicrobial activity. This approach utilizes a panel of bioluminescent bacteria, whose light production is a sensitive indicator of various cellular effects [...] Read more.

This study presents a rapid and comprehensive method for screening mushroom extracts for the putative discovery of bioactive molecules, including those exhibiting antimicrobial activity. This approach utilizes a panel of bioluminescent bacteria, whose light production is a sensitive indicator of various cellular effects triggered by the extracts, including disruption of bacterial communication (quorum sensing), protein and DNA damage, fatty acid metabolism alterations, and oxidative stress induction. The bioassay’s strength is its ability to efficiently analyze a large number of extracts simultaneously while also assessing several different mechanisms of toxicity, significantly reducing screening time. All samples analyzed exhibited more than one cellular effect, as indicated by the reporter bacteria. Four samples (C. cornucopioides, F. fomentarius, I. obliquus, and M. giganteus) displayed the highest number (six) of possible mechanisms of antibacterial activity. Additionally, combining extraction and purification protocols with a bioluminescent bacterial panel enables simultaneous improvement of the desired antimicrobial properties of the extracts. The presented approach offers a valuable tool for uncovering the diverse antimicrobial mechanisms of mushroom extracts. Full article

(This article belongs to the Special Issue Prof. Shishmon Belkin 30th Anniversary of Working in Bioluminescent Bioreporter Bacteria Biosensors)

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20 pages, 7800 KiB

Open AccessArticle

Portable Miniaturized IoT-Enabled Point-of-Care Device for Electrochemical Sensing of Zopiclone in Cocktails

by María Gabriela Mejía-Méndez, Paula C. Cifuentes-Delgado, Sergio D. Gómez, Crhistian C. Segura, Nancy Ornelas-Soto and Johann F. Osma

Biosensors 2024, 14(11), 557; https://doi.org/10.3390/bios14110557 - 16 Nov 2024

Viewed by 511

Abstract

This study proposes a portable and IoT-based electrochemical point-of-care sensing device for detecting zopiclone in cocktails. The system utilizes an electrochemical laccase biosensor and a potentiostat, offering a low-cost and portable device for detecting this sedative drug in cocktails. The sensor characterization experiments [...] Read more.

This study proposes a portable and IoT-based electrochemical point-of-care sensing device for detecting zopiclone in cocktails. The system utilizes an electrochemical laccase biosensor and a potentiostat, offering a low-cost and portable device for detecting this sedative drug in cocktails. The sensor characterization experiments demonstrated the linear behavior of the oxidation and reduction currents for each of the targeted concentrations of zopiclone, enabling their detection and quantification even when mixed with an interfering substance. The proposed system could be used for the in situ analysis of cocktails, providing a valuable tool for monitoring the presence of hypnotic drugs in various social and clinical settings. The study utilized materials and reagents, including zopiclone, lab-made lemon juice, lab-made tequila, and lab-made triple sec, all prepared with reactants obtained in Bogotá, Colombia. The potentiostat used in the system was designed to manage cyclic voltammetry measurements. The electrochemical cells’ durability and longevity were also tested and characterized, with all electrodes undergoing 200 tests and their performance degradation varying according to the molecule used. The study concludes that the proposed system offers a valuable tool for detecting and monitoring pharmaceutical substances in various interfering ingredients that build up cocktails. Further research and application of this system can help address the global concern surrounding the administration of hypnotic substances to unknowing consumers through food or drinks to enable robbery and sexual assault. Full article

(This article belongs to the Special Issue Electrochemical Biosensing Platforms for Food, Drug and Health Safety)

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34 pages, 3181 KiB

Open AccessReview

Commercial Wearables for the Management of People with Autism Spectrum Disorder: A Review

by Jonathan Hernández-Capistrán, Giner Alor-Hernández, Humberto Marín-Vega, Maritza Bustos-López, Laura Nely Sanchez-Morales and Jose Luis Sanchez-Cervantes

Biosensors 2024, 14(11), 556; https://doi.org/10.3390/bios14110556 - 15 Nov 2024

Viewed by 566

Abstract

Autism Spectrum Disorder (ASD) necessitates comprehensive management, addressing complex challenges in social communication, behavioral regulation, and sensory processing, for which wearable technologies offer valuable tools to monitor and support interventions. Therefore, this review explores recent advancements in wearable technology, categorizing devices based on [...] Read more.

Autism Spectrum Disorder (ASD) necessitates comprehensive management, addressing complex challenges in social communication, behavioral regulation, and sensory processing, for which wearable technologies offer valuable tools to monitor and support interventions. Therefore, this review explores recent advancements in wearable technology, categorizing devices based on executive function, psychomotor skills, and the behavioral/emotional/sensory domain, highlighting their potential to improve ongoing management and intervention. To ensure rigor and comprehensiveness, the review employs a PRISMA-based methodology. Specifically, literature searches were conducted across diverse databases, focusing on studies published between 2014 and 2024, to identify the most commonly used wearables in ASD research. Notably, 55.45% of the 110 devices analyzed had an undefined FDA status, 23.6% received 510(k) clearance, and only a small percentage were classified as FDA Breakthrough Devices or in the submission process. Additionally, approximately 50% of the devices utilized sensors like ECG, EEG, PPG, and EMG, highlighting their widespread use in real-time physiological monitoring. Our work comprehensively analyzes a wide array of wearable technologies, including emerging and advanced. While these technologies have the potential to transform ASD management through real-time data collection and personalized interventions, improved clinical validation and user-centered design are essential for maximizing their effectiveness and user acceptance. Full article

(This article belongs to the Special Issue Recent Advances in Wearable Biosensors for Human Health Monitoring)

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14 pages, 2350 KiB

Open AccessArticle

Ultra-Selective and Sensitive Fluorescent Chemosensor Based on Phage Display-Derived Peptide with an N-Terminal Cu(II)-Binding Motif

by Marta Sosnowska, Tomasz Łęga, Dawid Nidzworski, Marcin Olszewski and Beata Gromadzka

Biosensors 2024, 14(11), 555; https://doi.org/10.3390/bios14110555 - 14 Nov 2024

Viewed by 508

Abstract

Copper, along with gold, was among the first metals that humans employed. Thus, the copper pollution of the world’s water resources is escalating, posing a significant threat to human health and aquatic ecosystems. It is crucial to develop detection technology that is both [...] Read more.

Copper, along with gold, was among the first metals that humans employed. Thus, the copper pollution of the world’s water resources is escalating, posing a significant threat to human health and aquatic ecosystems. It is crucial to develop detection technology that is both low-cost and feasible, as well as ultra-selective and sensitive. This study explored the use of the NH₂-Xxx-His motif-derived peptide from phage display technology for ultra-selective Cu²⁺ detection. Various Cu-binding M13 phage clones were isolated, and their affinity and cross-reactivity for different metal ions were determined. A detailed analysis of the amino acid sequence of the unique Cu-binding peptides was employed. For the development of an optical chemosensor, a peptide with an NH₂-Xxx-His motif was selected. The dansyl group was incorporated during solid-phase peptide synthesis, and fluorescence detection assays were employed. The efficacy of the Cu²⁺-binding peptide was verified through spectroscopic measurements. In summary, we developed a highly selective and sensitive fluorescent chemosensor for Cu²⁺ detection based on a peptide sequence from a phage display library that carries the N-terminal Xxx-His motif. Full article

(This article belongs to the Special Issue Application of Biosensors in Environmental Monitoring)

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19 pages, 9106 KiB

Open AccessReview

Chemical Heating for Minimally Instrumented Point-of-Care (POC) Molecular Diagnostics

by Michael G. Mauk, Felix Ansah and Mohamed El-Tholoth

Biosensors 2024, 14(11), 554; https://doi.org/10.3390/bios14110554 - 13 Nov 2024

Viewed by 523

Abstract

The minimal instrumentation of portable medical diagnostic devices for point-of-care applications is facilitated by using chemical heating in place of temperature-regulated electrical heaters. The main applications are for isothermal nucleic acid amplification tests (NAATs) and other enzymatic assays that require elevated, controlled temperatures. [...] Read more.

The minimal instrumentation of portable medical diagnostic devices for point-of-care applications is facilitated by using chemical heating in place of temperature-regulated electrical heaters. The main applications are for isothermal nucleic acid amplification tests (NAATs) and other enzymatic assays that require elevated, controlled temperatures. In the most common implementation, heat is generated by the exothermic reaction of a metal (e.g., magnesium, calcium, or lithium) with water or air, buffered by a phase-change material that maintains a near-constant temperature to heat the assay reactions. The ability to incubate NAATs electricity-free and to further to detect amplification with minimal instrumentation opens the door for fully disposable, inexpensive molecular diagnostic devices that can be used for pathogen detection as needed in resource-limited areas and during natural disasters, wars, and civil disturbances when access to electricity may be interrupted. Several design approaches are reviewed, including more elaborate schemes for multiple stages of incubation at different temperatures. Full article

(This article belongs to the Special Issue Biosensors Based on Isothermal Nucleic Acid Amplification Strategies)

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19 pages, 5570 KiB

Open AccessArticle

Hybrid Functional Near-Infrared Spectroscopy System and Electromyography for Prosthetic Knee Control

by Nouf Jubran AlQahtani, Ibraheem Al-Naib, Ijlal Shahrukh Ateeq and Murad Althobaiti

Biosensors 2024, 14(11), 553; https://doi.org/10.3390/bios14110553 - 13 Nov 2024

Viewed by 639

Abstract

The increasing number of individuals with limb loss worldwide highlights the need for advancements in prosthetic knee technology. To improve control and quality of life, integrating brain–computer communication with motor imagery offers a promising solution. This study introduces a hybrid system that combines [...] Read more.

The increasing number of individuals with limb loss worldwide highlights the need for advancements in prosthetic knee technology. To improve control and quality of life, integrating brain–computer communication with motor imagery offers a promising solution. This study introduces a hybrid system that combines electromyography (EMG) and functional near-infrared spectroscopy (fNIRS) to address these limitations and enhance the control of knee movements for individuals with above-knee amputations. The study involved an experiment with nine healthy male participants, consisting of two sessions: real execution and imagined execution using motor imagery. The OpenBCI Cyton board collected EMG signals corresponding to the desired movements, while fNIRS monitored brain activity in the prefrontal and motor cortices. The analysis of the simultaneous measurement of the muscular and hemodynamic responses demonstrated that combining these data sources significantly improved the classification accuracy compared to using each dataset alone. The results showed that integrating both the EMG and fNIRS data consistently achieved a higher classification accuracy. More specifically, the Support Vector Machine performed the best during the motor imagery tasks, with an average accuracy of 49.61%, while the Linear Discriminant Analysis excelled in the real execution tasks, achieving an average accuracy of 89.67%. This research validates the feasibility of using a hybrid approach with EMG and fNIRS to enable prosthetic knee control through motor imagery, representing a significant advancement potential in prosthetic technology. Full article

(This article belongs to the Section Wearable Biosensors)

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29 pages, 4900 KiB

Open AccessArticle

Physicochemical Rationale of Matrix Effects Involved in the Response of Hydrogel-Embedded Luminescent Metal Biosensors

by Elise Rotureau, Christophe Pagnout and Jérôme F. L. Duval

Biosensors 2024, 14(11), 552; https://doi.org/10.3390/bios14110552 - 13 Nov 2024

Viewed by 608

Abstract

There is currently a critical need for understanding how the response and activity of whole-cell bacterial reporters positioned in a complex biological or environmental matrix are impacted by the physicochemical properties of their micro-environment. Accordingly, a comprehensive analysis of the bioluminescence response of [...] Read more.

There is currently a critical need for understanding how the response and activity of whole-cell bacterial reporters positioned in a complex biological or environmental matrix are impacted by the physicochemical properties of their micro-environment. Accordingly, a comprehensive analysis of the bioluminescence response of Cd(II)-inducible PzntA-luxCDABE Escherichia coli biosensors embedded in silica-based hydrogels is reported to decipher how metal bioavailability, cell photoactivity and ensuing light bioproduction are impacted by the hydrogel environment and the associated matrix effects. The analysis includes the account of (i) Cd speciation and accumulation in the host hydrogels, in connection with their reactivity and electrostatic properties, and (ii) the reduced bioavailability of resources for the biosensors confined (deep) inside the hydrogels. The measurements of the bioluminescence response of the Cd(II) inducible-lux biosensors in both hydrogels and free-floating cell suspensions are completed by those of the constitutive rrnB P1-luxCDABE E. coli so as to probe cell metabolic activity in these two situations. The approach contributes to unraveling the connections between the electrostatic hydrogel charge, the nutrient/metal bioavailabilities and the resulting Cd-triggered bioluminescence output. Biosensors are hosted in hydrogels with thickness varying between 0 mm (the free-floating cell situation) and 1.6 mm, and are exposed to total Cd concentrations from 0 to 400 nM. The partitioning of bioavailable metals at the hydrogel/solution interface following intertwined metal speciation, diffusion and Boltzmann electrostatic accumulation is addressed by stripping chronopotentiometry. In turn, we detail how the bioluminescence maxima generated by the Cd-responsive cells under all tested Cd concentration and hydrogel thickness conditions collapse remarkably well on a single plot featuring the dependence of bioluminescence on free Cd concentration at the individual cell level. Overall, the construction of this master curve integrates the contributions of key and often overlooked processes that govern the bioavailability properties of metals in 3D matrices. Accordingly, the work opens perspectives for quantitative and mechanistic monitoring of metals by biosensors in environmental systems like biofilms or sediments. Full article

(This article belongs to the Section Environmental Biosensors and Biosensing)

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15 pages, 1885 KiB

Open AccessArticle

Innovative Peptide-Based Plasmonic Optical Biosensor for the Determination of Cholesterol

by Ana Lia Bernardo, Anne Parra, Virginia Cebrián, Óscar Ahumada, Sergio Oddi and Enrico Dainese

Biosensors 2024, 14(11), 551; https://doi.org/10.3390/bios14110551 - 13 Nov 2024

Viewed by 564

Abstract

Plasmonic-based biosensors have gained prominence as potent optical biosensing platforms in both scientific and medical research, attributable to their enhanced sensitivity and precision in detecting biomolecular and chemical interactions. However, the detection of low molecular weight analytes with high sensitivity and specificity remains [...] Read more.

Plasmonic-based biosensors have gained prominence as potent optical biosensing platforms in both scientific and medical research, attributable to their enhanced sensitivity and precision in detecting biomolecular and chemical interactions. However, the detection of low molecular weight analytes with high sensitivity and specificity remains a complex and unresolved issue, posing significant limitations for the advancement of clinical diagnostic tools and medical device technologies. Notably, abnormal cholesterol levels are a well-established indicator of various pathological conditions; yet, the quantitative detection of the free form of cholesterol is complicated by its small molecular size, pronounced hydrophobicity, and the necessity for mediator molecules to achieve efficient sensing. In the present study, a novel strategy for cholesterol quantification was developed, leveraging a plasmonic optical readout in conjunction with a highly specific cholesterol-binding peptide (C-pept) as a biorecognition element, anchored on a functionalized silica substrate. The resulting biosensor exhibited an exceptionally low detection limit of 21.95 µM and demonstrated a linear response in the 10–200 µM range. This peptide-integrated plasmonic sensor introduces a novel one-step competitive method for cholesterol quantification, positioning itself as a highly sensitive biosensing modality for implementation within the AVAC platform, which operates using reflective dark-field microscopy. Full article

(This article belongs to the Special Issue Nanotechnology-Enabled Biosensors)

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12 pages, 6188 KiB

Open AccessArticle

Bi-Plane Multicolor Scanning Illumination Microscopy with Multispot Excitation and a Distorted Diffraction Grating

by Siwei Li, Yunke Zhang, Zhiwen Liao, Zengyuan Tian, Hairulazwan Hashim, Youjun Zeng and Yandong Zhang

Biosensors 2024, 14(11), 550; https://doi.org/10.3390/bios14110550 - 13 Nov 2024

Viewed by 395

Abstract

Multifocus microscopy has previously been demonstrated to provide volumetric information from a single shot. However, the practical application of this method is challenging due to its weak optical sectioning and limited spatial resolution. Here, we report on the combination of a distorted diffraction [...] Read more.

Multifocus microscopy has previously been demonstrated to provide volumetric information from a single shot. However, the practical application of this method is challenging due to its weak optical sectioning and limited spatial resolution. Here, we report on the combination of a distorted diffraction grating and multifocal scanning illumination microscopy to improve spatial resolution and contrast. DG is introduced in the emission path of the multifocal scanning illumination microscopy, which splits the fluorescence signal from different sample layers into different diffraction orders. After postprocessing, super-resolution wide-field images of different sample layers can be reconstructed from single 2D scanning. Full article

(This article belongs to the Special Issue Advanced Optical Methods for Biosensing)

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15 pages, 8475 KiB

Open AccessArticle

A Novel High-Throughput Sample-in-Result-Out Device for the Rapid Detection of Viral Nucleic Acids

by Fangning Wang, Fei Hu, Yunyun Zhang, Xichen Li, Qin Ma, Xincheng Wang and Niancai Peng

Biosensors 2024, 14(11), 549; https://doi.org/10.3390/bios14110549 - 13 Nov 2024

Viewed by 441

Abstract

Clustered regularly interspaced short palindromic repeats (CRISPR) molecular diagnostic technology is one of the most reliable diagnostic tools for infectious diseases due to its short reaction time, high sensitivity, and excellent specificity. However, compared with fluorescent polymerase chain reaction (PCR) technology, CRISPR molecular [...] Read more.

Clustered regularly interspaced short palindromic repeats (CRISPR) molecular diagnostic technology is one of the most reliable diagnostic tools for infectious diseases due to its short reaction time, high sensitivity, and excellent specificity. However, compared with fluorescent polymerase chain reaction (PCR) technology, CRISPR molecular diagnostic technology lacks high-throughput automated instrumentation and standardized detection reagents for high sensitivity, limiting its large-scale clinical application. In this study, a high-throughput automated device was developed by combining reagent lyophilization, extraction-free technology, and a one-pot consumable system. This innovative approach enabled the rapid sample-in-result-out detection of 48 samples in 25 min and demonstrated high sensitivity and specificity for the qualitative analysis of clinical samples. The obtained results show that the detection limit of the designed system for African swine fever virus (ASFV) is 0.5 copies/μL. As a proof concept, a single-tube dual-target nucleic acid detection method was developed, achieving a detection limit of 5 copies/μL for the ORF1ab and N genes of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) within 45 min. The method is highly specific, reliable, and stable, providing a feasible solution for the clinical application of CRISPR nucleic acid detection technology. Full article

(This article belongs to the Special Issue Biosensing Technologies in Medical Diagnosis)

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16 pages, 7688 KiB

Open AccessArticle

Enhanced Detection of Vibrio harveyi Using a Dual-Composite DNAzyme-Based Biosensor

by Siying Li, Shuai Zhang, Weihong Jiang, Yuying Wang, Mingwang Liu, Mingsheng Lyu and Shujun Wang

Biosensors 2024, 14(11), 548; https://doi.org/10.3390/bios14110548 - 13 Nov 2024

Viewed by 460

Abstract

Vibrio harveyi is a serious bacterial pathogen which can infect a wide range of marine organisms, such as marine fish, invertebrates, and shrimp, in aquaculture, causing severe losses. In addition, V. harveyi can be transmitted through food and water, infecting humans and posing [...] Read more.

Vibrio harveyi is a serious bacterial pathogen which can infect a wide range of marine organisms, such as marine fish, invertebrates, and shrimp, in aquaculture, causing severe losses. In addition, V. harveyi can be transmitted through food and water, infecting humans and posing a serious threat to public safety. Therefore, rapid and accurate detection of this pathogen is key for the prevention and control of related diseases. In this study, nine rounds of in vitro screening were conducted with Systematic Evolution of Ligands by Exponential Enrichment (SELEX) technology using unmodified DNA libraries, targeting the crude extracellular matrix (CEM) of V. harveyi. Two DNAzymes, named DVh₁ and DVh₃, with high activity and specificity were obtained. Furthermore, a fluorescent biosensor with dual DNAzymes was constructed which exhibited improved detection efficiency. The sensor showed a good fluorescence response to multiple aquatic products (i.e., fish, shrimp, and shellfish) infected with V. harveyi, with a detection limit below 11 CFU/mL. The fluorescence signal was observed within 30 min of reaction after target addition. This simple, inexpensive, highly effective, and easy to operate DNAzymes biosensor can be used for field detection of V. harveyi. Full article

(This article belongs to the Section Optical and Photonic Biosensors)

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12 pages, 1852 KiB

Open AccessArticle

Development of an Escherichia coli Cell-Based Biosensor for Aspirin Monitoring by Genetic Engineering of MarR

by Yeonhong Kim, Yangwon Jeon, Kyeoungseok Song, Haekang Ji, Soon-Jin Hwang and Youngdae Yoon

Biosensors 2024, 14(11), 547; https://doi.org/10.3390/bios14110547 - 12 Nov 2024

Viewed by 578

Abstract

Multiple antibiotic resistance regulators (MarRs) control the transcription of genes in the mar operon of Escherichia coli in the presence of salicylic acid (SA). The interaction with SA induces conformational changes in the MarR released from the promoter of the mar operon, turning [...] Read more.

Multiple antibiotic resistance regulators (MarRs) control the transcription of genes in the mar operon of Escherichia coli in the presence of salicylic acid (SA). The interaction with SA induces conformational changes in the MarR released from the promoter of the mar operon, turning on transcription. We constructed an SA-specific E. coli cell-based biosensor by fusing the promoter of the mar operon (P_marO) and the gene that encodes an enhanced green fluorescent protein (egfp). Because SA and aspirin are structurally similar, a biosensor for monitoring aspirin can be obtained by genetically engineering MarR to be aspirin (ASP)-responsive. To shift the selectivity of MarR toward ASP, we changed the residues around the ligand-binding sites by site-directed mutagenesis. We examined the effects of genetic engineering on MarR by introducing MarRs with P_marO-egfp into E. coli. Among the tested mutants, MarR T72A improved the ASP responses by approximately 3 times compared to the wild-type MarR, while still showing an SA response. Although the MarR T72A biosensor exhibited mutual interference between SA and ASP, it accurately determined the ASP concentration in spiked water and medicine samples with over 90% accuracy. While the ASP biosensors still require improvement, our results provide valuable insights for developing E. coli cell-based biosensors for ASP and transcription factor-based biosensors in general. Full article

(This article belongs to the Special Issue Cell-Based Biosensors for Rapid Detection and Monitoring)

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10 pages, 2982 KiB

Open AccessCommunication

Preliminary Investigation of a Potential Optical Biosensor Using the Diamond™ Nucleic Acid Dye Applied to DNA and Friction Ridge Analysis from Fingerprint Traces

by Martyna Czarnomska, Aneta Lewkowicz, Emilia Gruszczyńska, Katarzyna Walczewska-Szewc, Zygmunt Gryczyński, Piotr Bojarski and Sławomir Steinborn

Biosensors 2024, 14(11), 546; https://doi.org/10.3390/bios14110546 - 11 Nov 2024

Viewed by 578

Abstract

Developments in science and technology lead to an increasing use of scientific evidence in litigation. Interdisciplinary research can improve current procedures and introduce new ones for the disclosure and examination of evidence. The dactyloscopic trace is used for personal identification by matching minutiae [...] Read more.

Developments in science and technology lead to an increasing use of scientific evidence in litigation. Interdisciplinary research can improve current procedures and introduce new ones for the disclosure and examination of evidence. The dactyloscopic trace is used for personal identification by matching minutiae (the minimum required may vary by country) or for extracting DNA material from the trace under investigation. The research presented in this article aims to propose the merging of two currently used personal identification methods, DNA analysis and dactyloscopic trace analysis, which are currently treated as separate forensic traces found at a crime scene. Namely, the forensic trace to be analyzed is the dactyloscopic trace containing DNA, and both sources of information needed for identification are examined as one. Promega’s Diamond™ Nucleic Acid Dye, presented as a safe alternative to ethidium bromide, works by binding to single- and double-stranded DNA and is used to visualize the separation of material in a gel and to detect DNA in forensic samples. Spectroscopic studies as absorption and emission spectra and fluorescence microscopy observations presented in our research confirm that Diamond™ Nucleic Acid Dye can also be used to visualize fingerprints on non-absorbent surfaces and that combining the two methods into one can significantly increase the evidential value and contribute to the design of an innovative fast-acting optical biosensor. Full article

(This article belongs to the Special Issue Advanced Materials in Nano-Photonics and Biosensor Systems)

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12 pages, 2926 KiB

Open AccessArticle

Rapid Microfluidic Biosensor for Point-of-Care Determination of Rheumatoid Arthritis via Anti-Cyclic Citrullinated Peptide Antibody Detection

by Wei-Yu Tai, To-Lin Chen, Hsing-Meng Wang and Lung-Ming Fu

Biosensors 2024, 14(11), 545; https://doi.org/10.3390/bios14110545 - 10 Nov 2024

Viewed by 589

Abstract

Rheumatoid arthritis (RA) is a chronic autoimmune disorder that causes extensive damage to multiple organs and tissues and has no known cure. This study introduces a microfluidic detection platform that combines a microfluidic reaction chip with a micro-spectrometer to accurately detect the anti-cyclic [...] Read more.

Rheumatoid arthritis (RA) is a chronic autoimmune disorder that causes extensive damage to multiple organs and tissues and has no known cure. This study introduces a microfluidic detection platform that combines a microfluidic reaction chip with a micro-spectrometer to accurately detect the anti-cyclic citrullinated peptide antibody (anti-CCP Ab) biomarker, commonly associated with arthritis. The surface of the microfluidic reaction chip is functionalized using streptavidin to enable the subsequent immobilization of biotinylated-labeled cyclic citrullinated peptide (biotin–CCP) molecules through a streptavidin–biotin reaction. The modified chip is then exposed to anti-CCP Ab, second antibody conjugated with horseradish peroxidase (HRP) (2nd Ab-HRP), 3,3′,5,5′-tetramethylbenzidine (TMB), and a stop solution. Finally, the concentration of the anti-CCP Ab biomarker is determined by analyzing the optical density (OD) of the colorimetric reaction product at 450 nm using a micro-spectrometer. The detection platform demonstrated a strong correlation (R² = 0.9966) between OD and anti-CCP Ab concentration. This was based on seven control samples with anti-CCP Ab concentrations ranging from 0.625 to 100 ng/mL. Moreover, for 30 artificial serum samples with unknown anti-CCP Ab concentrations, the biosensor achieves a correlation coefficient of (R² = 0.9650). The proposed microfluidic detection platform offers a fast and effective method for accurately identifying and quantifying the anti-CCP Ab biomarker. Thus, it offers a valuable tool for the early diagnosis and monitoring of RA and its progression in point-of-care settings. Full article

(This article belongs to the Special Issue Design, Fabrication, and Applications of Microfluidic Devices for Biosensing)

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15 pages, 3817 KiB

Open AccessArticle

β-Cyclodextrin Functionalized Au@Ag Core-Shell Nanoparticles: Plasmonic Sensors for Cysteamine and Efficient Nanocatalysts for Nitrobenzene-to-Aniline Conversion

by Ramar Rajamanikandan, Kandasamy Sasikumar and Heongkyu Ju

Biosensors 2024, 14(11), 544; https://doi.org/10.3390/bios14110544 - 9 Nov 2024

Viewed by 694

Abstract

We reported the gold/silver core-shell nanoparticles (Au_core@Ag_shell NPs) functionalized with β-cyclodextrin (β-CD) as versatile nano-agents demonstrated for human urine-based biosensing of cysteamine and catalytic conversion from nitrobenzene (NB) to aniline. First, the hybrid bimetallic nanoparticles, i.e., β-CD-Au_core@Ag_shell [...] Read more.

We reported the gold/silver core-shell nanoparticles (Au_core@Ag_shell NPs) functionalized with β-cyclodextrin (β-CD) as versatile nano-agents demonstrated for human urine-based biosensing of cysteamine and catalytic conversion from nitrobenzene (NB) to aniline. First, the hybrid bimetallic nanoparticles, i.e., β-CD-Au_core@Ag_shell NPs, constituted a colorimetric sensing platform based on localized surface plasmons, enabling cysteamine (Cyst) to be detected in a remarkably rapid manner, i.e., within 2 min, which was greatly shortened in comparison with that of our previous report. This was due largely to use of β-CD being effectively replaceable by Cyst. The detection of Cyst was demonstrated using human urine specimens in the linear range of 25–750 nM with a limit of detection of 1.83 nM. Excellent specificity in detecting Cyst was also demonstrated against potential interfering molecules. Meanwhile, the β-CD-Au_core@Ag_shell NPs were demonstrated as nanocatalysts for converting NB to aniline with efficiency enhanced by more than three-fold over the pure gold nanoparticles previously reported, due to the dual functions of the structural core-shell. The demonstrated versatile features of the hybrid nanoparticles can find applications in human urine-based biosensors for Cyst detection, and in the screening of Cyst-containing drugs, while detoxicating NB for ecological protection in aqueous media. Full article

(This article belongs to the Special Issue Nanomaterial-Enhanced Biosensing for Point-of-Care Diagnostics)

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14 pages, 4453 KiB

Open AccessArticle

An Enzyme-Free Impedimetric Sensor Based on Flower-like NiO/Carbon Microspheres for L-Glutamic Acid Assay

by Najva Sadri, Mohammad Mazloum-Ardakani, Farzaneh Asadpour, Yvonne Joseph and Parvaneh Rahimi

Biosensors 2024, 14(11), 543; https://doi.org/10.3390/bios14110543 - 9 Nov 2024

Viewed by 468

Abstract

This research introduces a non-enzymatic electrochemical sensor utilizing flower-like nickel oxide/carbon (fl-NiO/C) microspheres for the precise detection of L-glutamic acid (LGA), a crucial neurotransmitter in the field of healthcare and a frequently utilized food additive and flavor enhancer. The fl-NiO/C were synthesized with [...] Read more.

This research introduces a non-enzymatic electrochemical sensor utilizing flower-like nickel oxide/carbon (fl-NiO/C) microspheres for the precise detection of L-glutamic acid (LGA), a crucial neurotransmitter in the field of healthcare and a frequently utilized food additive and flavor enhancer. The fl-NiO/C were synthesized with controllable microstructures using metal–organic frameworks (MOFs) as precursors followed by a simple calcination process. The uniformly synthesized fl-NiO/C microspheres were further characterized using Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), and field emission scanning electron microscopy (FE-SEM). The fl-NiO/C was utilized as a modifier on the surface of a glassy carbon electrode, and an impedimetric sensor based on electrochemical impedance spectroscopy (EIS) was developed for the detection of LGA. The proposed sensor demonstrated excellent catalytic activity and selectivity towards LGA across a broad concentration range of 10–800 μM with a sensitivity of 486.9 µA.mM⁻¹.cm⁻² and a detection limit of 1.28 µM (S/N = 3). The sensor was also employed to identify LGA in blood plasma samples, yielding results that align with those obtained through HPLC. This achievement highlights the potential of fl-NiO/C microspheres in advancing cutting-edge biosensing applications. Full article

(This article belongs to the Special Issue Trends in Development of Biosensors for Disease Diagnosis, Treatment and Management—2nd Edition)

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26 pages, 4044 KiB

Open AccessReview

Research Trends in the Development of Block Copolymer-Based Biosensing Platforms

by Yong-Ho Chung and Jung Kwon Oh

Biosensors 2024, 14(11), 542; https://doi.org/10.3390/bios14110542 - 8 Nov 2024

Viewed by 476

Abstract

Biosensing technology, which aims to measure and control the signals of biological substances, has recently been developed rapidly due to increasing concerns about health and the environment. Top–down technologies have been used mainly with a focus on reducing the size of biomaterials to [...] Read more.

Biosensing technology, which aims to measure and control the signals of biological substances, has recently been developed rapidly due to increasing concerns about health and the environment. Top–down technologies have been used mainly with a focus on reducing the size of biomaterials to the nano-level. However, bottom–up technologies such as self-assembly can provide more opportunities to molecular-level arrangements such as directionality and the shape of biomaterials. In particular, block copolymers (BCPs) and their self-assembly have been significantly explored as an effective means of bottom–up technologies to achieve recent advances in molecular-level fine control and imaging technology. BCPs have been widely used in various biosensing research fields because they can artificially control highly complex nano-scale structures in a directionally controlled manner, and future application research based on interactions with biomolecules according to the development and synthesis of new BCP structures is greatly anticipated. Here, we comprehensively discuss the basic principles of BCPs technology, the current status of their applications in biosensing technology, and their limitations and future prospects. Rather than discussing a specific field in depth, this study comprehensively covers the overall content of BCPs as a biosensing platform, and through this, we hope to increase researchers’ understanding of adjacent research fields and provide research inspiration, thereby bringing about great advances in the relevant research fields. Full article

(This article belongs to the Special Issue Functional Materials for Biosensing Applications)

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24 pages, 7527 KiB

Open AccessReview

CRISPR–Cas Systems Associated with Electrolyte-Gated Graphene-Based Transistors: How They Work and How to Combine Them

by Pierre Guermonprez, Pierre Nioche, Louis Renaud, Nicolas Battaglini, Sébastien Sanaur, Eric Krejci and Benoît Piro

Biosensors 2024, 14(11), 541; https://doi.org/10.3390/bios14110541 - 7 Nov 2024

Viewed by 761

Abstract

In this review, recent advances in the combination of CRISPR–Cas systems with graphene-based electrolyte-gated transistors are discussed in detail. In the first part, the functioning of CRISPR–Cas systems is briefly explained, as well as the most common ways to convert their molecular activity [...] Read more.

In this review, recent advances in the combination of CRISPR–Cas systems with graphene-based electrolyte-gated transistors are discussed in detail. In the first part, the functioning of CRISPR–Cas systems is briefly explained, as well as the most common ways to convert their molecular activity into measurable signals. Other than optical means, conventional electrochemical transducers are also developed. However, it seems that the incorporation of CRISPR/Cas systems into transistor devices could be extremely powerful, as the former provides molecular amplification, while the latter provides electrical amplification; combined, the two could help to advance in terms of sensitivity and compete with conventional PCR assays. Today, organic transistors suffer from poor stability in biological media, whereas graphene materials perform better by being extremely sensitive to their chemical environment and being stable. The need for fast and inexpensive sensors to detect viral RNA arose on the occasion of the COVID-19 crisis, but many other RNA viruses are of interest, such as dengue, hepatitis C, hepatitis E, West Nile fever, Ebola, and polio, for which detection means are needed. Full article

(This article belongs to the Special Issue Feature Paper in Biosensor and Bioelectronic Devices 2024)

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23 pages, 6163 KiB

Open AccessReview

Recent Advance in Single-Molecule Fluorescent Biosensors for Tumor Biomarker Detection

by Jie Zhang, Jiawen Liu, Lixue Qiao, Qian Zhang, Juan Hu and Chun-yang Zhang

Biosensors 2024, 14(11), 540; https://doi.org/10.3390/bios14110540 - 7 Nov 2024

Viewed by 655

Abstract

The construction of biosensors for specific, sensitive, and rapid detection of tumor biomarkers significantly contributes to biomedical research and early cancer diagnosis. However, conventional assays often involve large sample consumption and poor sensitivity, limiting their further application in real samples. In recent years, [...] Read more.

The construction of biosensors for specific, sensitive, and rapid detection of tumor biomarkers significantly contributes to biomedical research and early cancer diagnosis. However, conventional assays often involve large sample consumption and poor sensitivity, limiting their further application in real samples. In recent years, single-molecule biosensing has emerged as a robust tool for detecting and characterizing biomarkers due to its unique advantages including simplicity, low sample consumption, ultra-high sensitivity, and rapid assay time. This review summarizes the recent advances in the construction of single-molecule biosensors for the measurement of various tumor biomarkers, including DNAs, DNA modifications, RNAs, and enzymes. We give a comprehensive review about the working principles and practical applications of these single-molecule biosensors. Additionally, we discuss the challenges and limitations of current single-molecule biosensors, and highlight the future directions. Full article

(This article belongs to the Special Issue Single-Molecule Biosensing: Recent Advances and Future Challenges)

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21 pages, 5531 KiB

Open AccessReview

Recapitulating Glioma Stem Cell Niches Using 3D Spheroid Models for Glioblastoma Research

by Hyunji Jo, Seulgi Lee, Min-Hyeok Kim, Sungsu Park and Seo-Yeon Lee

Biosensors 2024, 14(11), 539; https://doi.org/10.3390/bios14110539 - 7 Nov 2024

Viewed by 657

Abstract

Glioblastoma multiforme (GBM) is among the most aggressive brain cancers, and it contains glioma stem cells (GSCs) that drive tumor initiation, progression, and recurrence. These cells resist conventional therapies, contributing to high recurrence rates in GBM patients. Developing in vitro models that mimic [...] Read more.

Glioblastoma multiforme (GBM) is among the most aggressive brain cancers, and it contains glioma stem cells (GSCs) that drive tumor initiation, progression, and recurrence. These cells resist conventional therapies, contributing to high recurrence rates in GBM patients. Developing in vitro models that mimic the tumor microenvironment (TME), particularly the GSC niche, is crucial for understanding GBM growth and therapeutic resistance. Three-dimensional (3D) spheroid models provide a more physiologically relevant approach than traditional two-dimensional (2D) cultures, recapitulating key tumor features like hypoxia, cell heterogeneity, and drug resistance. This review examines scaffold-free and scaffold-based methods for generating 3D GBM spheroids, focusing on their applications in studying the cancer stem cell niche. The discussion encompasses methods such as the hanging drop, low-adhesion plates, and magnetic levitation, alongside advancements in embedding spheroids within extracellular matrix-based hydrogels and employing 3D bioprinting to fabricate more intricate tumor models. These 3D culture systems offer substantial potential for enhancing our understanding of GBM biology and devising more effective targeted therapies. Full article

(This article belongs to the Special Issue Microfluidics and Organ-on-a-Chip for Disease Modeling and Drug Screening (2nd Edition))

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15 pages, 4493 KiB

Open AccessArticle

Baseline Raman Spectral Fingerprints of Zebrafish Embryos and Larvae

by Isabel Oliveira Abreu, Cláudia Teixeira, Rui Vilarinho, A. Cristina S. Rocha, Joaquim Agostinho Moreira, Luís Oliva-Teles, Laura Guimarães and António Paulo Carvalho

Biosensors 2024, 14(11), 538; https://doi.org/10.3390/bios14110538 - 6 Nov 2024

Viewed by 507

Abstract

As a highly sensitive vibrational technique, Raman spectroscopy (RS) can provide valuable chemical and molecular data useful to characterise animal cell types, tissues and organs. As a label-free, rapid detection method, RS has been considered a valuable asset in forensics, biology and medicine. [...] Read more.

As a highly sensitive vibrational technique, Raman spectroscopy (RS) can provide valuable chemical and molecular data useful to characterise animal cell types, tissues and organs. As a label-free, rapid detection method, RS has been considered a valuable asset in forensics, biology and medicine. The technique has been applied to zebrafish for various purposes, including physiological, biochemical or bioaccumulation analyses. The available data point out its potential for the early diagnosis of detrimental effects elicited by toxicant exposure. Nevertheless, no baseline spectra are available for zebrafish embryos and larvae that could allow for suitable planning of toxicological assessments, comparison with toxicant-elicited spectra or mechanistic understanding of biochemical and physiological responses to the exposures. With this in mind, this work carried out a baseline characterisation of Raman spectra of zebrafish embryos and larvae throughout early development. Raman spectra were recorded from the iris, forebrain, melanocytes, heart, muscle and swim bladder between 24 and 168 h post-fertilisation. A chemometrics approach, based on partial least-squares discriminant analysis (PLS-DA), was used to obtain a Raman characterisation of each tissue or organ. In total, 117 Raman bands were identified, of which 24 were well represented and, thus, retained in the data analysed. Only three bands were found to be common to all organs and tissues. The PLS-DA provided a tentative Raman spectral fingerprint typical of each tissue or organ, reflecting the ongoing developmental dynamics. The bands showed frequencies previously assigned to collagen, cholesterol, various essential amino acids, carbohydrates and nucleic acids. Full article

(This article belongs to the Special Issue Optical Biosensors: Advances and New Perspectives)

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19 pages, 8697 KiB

Open AccessReview

In Situ and Label-Free Quantification of Membrane Protein–Ligand Interactions Using Optical Imaging Techniques: A Review

by Caixin Huang, Jingbo Zhang, Zhaoyang Liu, Jiying Xu, Ying Zhao and Pengfei Zhang

Biosensors 2024, 14(11), 537; https://doi.org/10.3390/bios14110537 - 6 Nov 2024

Viewed by 565

Abstract

Membrane proteins are crucial for various cellular processes and are key targets in pharmacological research. Their interactions with ligands are essential for elucidating cellular mechanisms and advancing drug development. To study these interactions without altering their functional properties in native environments, several advanced [...] Read more.

Membrane proteins are crucial for various cellular processes and are key targets in pharmacological research. Their interactions with ligands are essential for elucidating cellular mechanisms and advancing drug development. To study these interactions without altering their functional properties in native environments, several advanced optical imaging methods have been developed for in situ and label-free quantification. This review focuses on recent optical imaging techniques such as surface plasmon resonance imaging (SPRi), surface plasmon resonance microscopy (SPRM), edge tracking approaches, and surface light scattering microscopy (SLSM). We explore the operational principles, recent advancements, and the scope of application of these methods. Additionally, we address the current challenges and explore the future potential of these innovative optical imaging strategies in deepening our understanding of biomolecular interactions and facilitating the discovery of new therapeutic agents. Full article

(This article belongs to the Special Issue Feature Paper in Biosensor and Bioelectronic Devices 2024)

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14 pages, 2414 KiB

Open AccessArticle

Development of a Recombinase Polymerase Amplification-Coupled CRISPR/Cas12a Platform for Rapid Detection of Antimicrobial-Resistant Genes in Carbapenem-Resistant Enterobacterales

by Ji Woo Yang, Heesu Kim, Lee-Sang Hyeon, Jung Sik Yoo and Sangrim Kang

Biosensors 2024, 14(11), 536; https://doi.org/10.3390/bios14110536 - 5 Nov 2024

Viewed by 698

Abstract

The worldwide spread of carbapenemase-producing Enterobacterales (CPE) represents a significant threat owing to the high mortality and morbidity rates. Traditional diagnostic methods are often too slow and complex for rapid point-of-care testing. Therefore, we developed a recombinase polymerase amplification (RPA)-coupled CRISPR/Cas12a system (RCCS), [...] Read more.

The worldwide spread of carbapenemase-producing Enterobacterales (CPE) represents a significant threat owing to the high mortality and morbidity rates. Traditional diagnostic methods are often too slow and complex for rapid point-of-care testing. Therefore, we developed a recombinase polymerase amplification (RPA)-coupled CRISPR/Cas12a system (RCCS), a rapid, accurate, and simple diagnostic platform for detecting antimicrobial-resistant genes. The RCCS detected carbapenemase genes (bla_KPC and bla_NDM) within 50 min, including 10 min for DNA extraction and 30–40 min for RCCS reaction (a 20 min RPA reaction with a 10–20-min CRISPR/Cas12a assay). Fluorescence signals obtained from the RCCS platform were visualized using lateral-flow test strips (LFSs) and real-time and endpoint fluorescence. The LFS clearly displayed test lines while detecting carbapenemase genes. Furthermore, the RCCS platform demonstrated high sensitivity by successfully detecting bla_KPC and bla_NDM at the attomolar and picomolar levels, respectively. The accuracy of the RCCS platform was validated with clinical isolates of Klebsiella pneumoniae and Escherichia coli; a 100% detection accuracy was achieved, which has not been reported when using conventional PCR. Overall, these findings indicate that the RCCS platform is a powerful tool for rapid and reliable detection of carbapenemase-encoding genes, with significant potential for implementation in point-of-care settings and resource-limited environments. Full article

(This article belongs to the Section Biosensors and Healthcare)

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15 pages, 4571 KiB

Open AccessArticle

Lateral Flow Assay for Preeclampsia Screening Using DNA Hairpins and Surface-Enhanced Raman-Active Nanoprobes Targeting hsa-miR-17-5p

by Ka Wai Ng, Siddhant Jaitpal, Ngoc Nhu Vu, Angela Michelle T. San Juan, Sayantan Tripathy, Rohit Sai Kodam, Abhishek Bastiray, Jae-Hyun Cho, Mahua Choudhury, Gerard L. Coté and Samuel Mabbott

Biosensors 2024, 14(11), 535; https://doi.org/10.3390/bios14110535 - 5 Nov 2024

Viewed by 628

Abstract

Preeclampsia (PE) is a serious complication that poses risks to both mothers and their children. This condition is typically asymptomatic until the second or even third trimester, which can lead to poor outcomes and can be costly. Detection is particularly challenging in low- [...] Read more.

Preeclampsia (PE) is a serious complication that poses risks to both mothers and their children. This condition is typically asymptomatic until the second or even third trimester, which can lead to poor outcomes and can be costly. Detection is particularly challenging in low- and middle-income countries, where a lack of centralized testing facilities coincides with high rates of PE-related maternal mortality. Variations in the levels of hsa-miR-17-5p have been identified as constituting a potential early indicator for distinguishing between individuals with PE and those without PE during the first trimester. Thus, developing a screening test to measure hsa-miR-17-5p levels would not only facilitate rapid detection in the early stages of pregnancy but also help democratize testing globally. Here, we present a proof-of-principle lateral-flow assay (LFA) designed to measure hsa-miR-17-5p levels using DNA-hairpin recognition elements for enhanced specificity and nanoprobes for sensitive surface-enhanced resonance Raman scattering (SERS) signal transduction. The theoretical limit of detection for hsa-miR-17-5p was 3.84 × 10⁻⁴ pg/µL using SERS. Full article

(This article belongs to the Special Issue Advances in Immunoassay Biosensing Platform for Point-of-Care Diagnostics)

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12 pages, 2423 KiB

Open AccessArticle

Gold–Graphene Quantum Dot Hybrid Nanoparticle for Smart Diagnostics of Prostate Cancer

by Divakar Raj, Arun Kumar, Dhruv Kumar, Krishna Kant and Ashish Mathur

Biosensors 2024, 14(11), 534; https://doi.org/10.3390/bios14110534 - 4 Nov 2024

Viewed by 1379

Abstract

Prostate cancer is one of the most prevalent cancers afflicting men worldwide, often detected at advanced stages, leading to increased mortality rates. Addressing this challenge, we present an innovative approach employing electrochemical biosensing for early-stage prostate cancer detection. This study used Indium–Tin Oxide [...] Read more.

Prostate cancer is one of the most prevalent cancers afflicting men worldwide, often detected at advanced stages, leading to increased mortality rates. Addressing this challenge, we present an innovative approach employing electrochemical biosensing for early-stage prostate cancer detection. This study used Indium–Tin Oxide (ITO) as a substrate and a deposited gold–graphene quantum dot (Au–GQD) nanohybrid to establish electrochemical sensing platforms for DNA-hybridization assays. A capturing DNA probe, PCA3, was covalently immobilized on the surface of the Au–GQDs and deposited electrochemically onto the ITO electrode surface. The Au–GQDs enabled the capturing of the target PCA3 biomarker probe. The sensor achieved a limit of detection (LoD) of up to 211 fM and presented a linear detection range spanning 1 µM to 100 fM. A rapid 5-min response time was also achieved. The tested shelf life of the pre-immobilized sensor was approximately 19 ± 1 days, with pronounced selectivity for its intended target amidst various interferants. The sensing device has the potential to revolutionize prostate cancer management by facilitating early-stage detection and screening with enhanced treatment efficacy. Full article

(This article belongs to the Special Issue Nano-Biosensors for Detection and Monitoring (2nd Edition))

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10 pages, 4702 KiB

Open AccessCommunication

Electrochemical Determination of B-Type Natriuretic Peptide with an Epitope-Imprinted Polymer-Based Sensor

by Kai-Hsi Liu, James L. Thomas, Pei-Chia Chu, Jing-Chen Ciou, Chuen-Yau Chen, Hung-Yin Lin and Mei-Hwa Lee

Biosensors 2024, 14(11), 533; https://doi.org/10.3390/bios14110533 - 4 Nov 2024

Viewed by 629

Abstract

B-type natriuretic peptides (BNP) are produced and secreted by the myocardium to reduce blood pressure and cardiac load. They cause vasodilation, natriuresis, growth suppression, and inhibition of the sympathetic nervous system and the renin–angiotensin–aldosterone system. The measurement of plasma BNP levels provides clinically [...] Read more.

B-type natriuretic peptides (BNP) are produced and secreted by the myocardium to reduce blood pressure and cardiac load. They cause vasodilation, natriuresis, growth suppression, and inhibition of the sympathetic nervous system and the renin–angiotensin–aldosterone system. The measurement of plasma BNP levels provides clinically useful information concerning the diagnosis and management of left ventricular dysfunction and heart failure, complementing other diagnostic testing procedures. In this work, three epitopes from the N-terminal (BNPnt), C-terminal (BNPct), and the cystine-bridged cyclic peptides (BNPr) of B-type natriuretic peptides were synthesized as templates for molecular imprinting. These peptides were doped into aniline (AN) and m-aminobenzenesulfonic acid (MSAN) for electropolymerization, thus forming epitope-imprinted poly(AN-co-MSAN) conductive films (EIPs). The monomer ratio was optimized using the electrochemical signals during polymerization. The optimized films were then characterized using a scanning electron microscope (SEM), atomic force microscope (AFM), and AC impedance. The electrochemical response of the films to the target peptides and to BNP was then measured. The sensing range of the EIPs-coated electrodes was from 0.001 to 1000 pg/mL for BNP. Finally, the BNP concentration in diluted serum samples was measured with the BNPrIP-coated electrode, giving 3.15 ± 0.07 pg/mL. By spiking the sample with known BNP concentrations, the accuracy was determined to be better than ±5%. Full article

(This article belongs to the Section Biosensor and Bioelectronic Devices)

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