Biosensors

17 pages, 1432 KiB

Open AccessReview

Open Hardware for Microfluidics: Exploiting Raspberry Pi Singleboard Computer and Camera Systems for Customisable Laboratory Instrumentation

by Rüya Meltem Sarıyer, Alexander Daniel Edwards and Sarah Helen Needs

Biosensors 2023, 13(10), 948; https://doi.org/10.3390/bios13100948 - 23 Oct 2023

Cited by 3 | Viewed by 4092

Abstract

The integration of Raspberry Pi miniature computer systems with microfluidics has revolutionised the development of low-cost and customizable analytical systems in life science laboratories. This review explores the applications of Raspberry Pi in microfluidics, with a focus on imaging, including microscopy and automated [...] Read more.

The integration of Raspberry Pi miniature computer systems with microfluidics has revolutionised the development of low-cost and customizable analytical systems in life science laboratories. This review explores the applications of Raspberry Pi in microfluidics, with a focus on imaging, including microscopy and automated image capture. By leveraging the low cost, flexibility and accessibility of Raspberry Pi components, high-resolution imaging and analysis have been achieved in direct mammalian and bacterial cellular imaging and a plethora of image-based biochemical and molecular assays, from immunoassays, through microbial growth, to nucleic acid methods such as real-time-qPCR. The control of image capture permitted by Raspberry Pi hardware can also be combined with onboard image analysis. Open-source hardware offers an opportunity to develop complex laboratory instrumentation systems at a fraction of the cost of commercial equipment and, importantly, offers an opportunity for complete customisation to meet the users’ needs. However, these benefits come with a trade-off: challenges remain for those wishing to incorporate open-source hardware equipment in their own work, including requirements for construction and operator skill, the need for good documentation and the availability of rapid prototyping such as 3D printing plus other components. These advances in open-source hardware have the potential to improve the efficiency, accessibility, and cost-effectiveness of microfluidic-based experiments and applications. Full article

(This article belongs to the Collection Recent Developments in Microfluidics)

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13 pages, 4723 KiB

Open AccessArticle

A Novel Optical Fiber Terahertz Biosensor Based on Anti-Resonance for The Rapid and Nondestructive Detection of Tumor Cells

by Zhe He, Yueping Luo, Guorong Huang, Marc Lamy de la Chapelle, Huiyan Tian, Fengxin Xie, Weidong Jin, Jia Shi, Xiang Yang and Weiling Fu

Biosensors 2023, 13(10), 947; https://doi.org/10.3390/bios13100947 - 23 Oct 2023

Cited by 2 | Viewed by 2004

Abstract

The sensitive and accurate detection of tumor cells is essential for successful cancer therapy and improving cancer survival rates. However, current tumor cell detection technologies have some limitations for clinical applications due to their complexity, low specificity, and high cost. Herein, we describe [...] Read more.

The sensitive and accurate detection of tumor cells is essential for successful cancer therapy and improving cancer survival rates. However, current tumor cell detection technologies have some limitations for clinical applications due to their complexity, low specificity, and high cost. Herein, we describe the design of a terahertz anti-resonance hollow core fiber (THz AR-HCF) biosensor that can be used for tumor cell detection. Through simulation and experimental comparisons, the low-loss property of the THz AR-HCF was verified, and the most suitable fiber out of multiple THz AR-HCFs was selected for biosensing applications. By measuring different cell numbers and different types of tumor cells, a good linear relationship between THz transmittance and the numbers of cells between 10 and 10⁶ was found. Meanwhile, different types of tumor cells can be distinguished by comparing THz transmission spectra, indicating that the biosensor has high sensitivity and specificity for tumor cell detection. The biosensor only required a small amount of sample (as low as 100 μL), and it enables label-free and nondestructive quantitative detection. Our flow cytometry results showed that the cell viability was as high as 98.5 ± 0.26% after the whole assay process, and there was no statistically significant difference compared with the negative control. This study demonstrates that the proposed THz AR-HCF biosensor has great potential for the highly sensitive, label-free, and nondestructive detection of circulating tumor cells in clinical samples. Full article

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

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11 pages, 2653 KiB

Open AccessArticle

Intensity Interrogation-Based High-Sensitivity Surface Plasmon Resonance Imaging Biosensor for Apoptosis Detection in Cancer

by Xin Yuan, Zhenxiao Niu, Lang Liu, Youjun Zeng, Lin Ma, Zhaogang Nie, Zhen Tian, Dongyun Kai, Fangteng Zhang, Guanyu Liu, Siwei Li and Zhengqiang Yuan

Biosensors 2023, 13(10), 946; https://doi.org/10.3390/bios13100946 - 23 Oct 2023

Cited by 4 | Viewed by 2147

Abstract

Intensity interrogation-based surface plasmon resonance imaging (ISPRi) sensing has a simple schematic design and is the most widely used surface plasmon resonance technology at present. In this study, we report the successful development of a novel high-sensitivity ISPRi biosensor and its application for [...] Read more.

Intensity interrogation-based surface plasmon resonance imaging (ISPRi) sensing has a simple schematic design and is the most widely used surface plasmon resonance technology at present. In this study, we report the successful development of a novel high-sensitivity ISPRi biosensor and its application for apoptosis detection in cancer cells. By optimizing the excitation wavelength and excitation angle, we achieved a refractive index resolution (RIR) of 5.20 × 10⁻⁶ RIU. Importantly, the biosensor has been tested and validated for high-throughput and label-free detection of activated caspase-3 with its specific inhibitor Z-DEVD-FMK in apoptotic cells. Therefore, this study describes a novel molecular imaging system to monitor apoptosis in cancers for disease diagnosis and/or evaluation of therapeutic efficacy of anti-cancer drugs. Full article

(This article belongs to the Special Issue Nano Biosensor and Its Application for In Vivo/Vitro Diagnosis)

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15 pages, 4380 KiB

Open AccessArticle

Isothermal Amplification and Hypersensitive Fluorescence Dual-Enhancement Nucleic Acid Lateral Flow Assay for Rapid Detection of Acinetobacter baumannii and Its Drug Resistance

by Qian Wang, Shuai Zheng, Yong Liu, Chongwen Wang, Bing Gu, Long Zhang and Shu Wang

Biosensors 2023, 13(10), 945; https://doi.org/10.3390/bios13100945 - 23 Oct 2023

Viewed by 2211

Abstract

Acinetobacter baumannii (A. baumannii) is among the main pathogens that cause nosocomial infections. The ability to rapidly and accurately detect A. baumannii and its drug resistance is essential for blocking secondary infections and guiding treatments. In this study, we reported a [...] Read more.

Acinetobacter baumannii (A. baumannii) is among the main pathogens that cause nosocomial infections. The ability to rapidly and accurately detect A. baumannii and its drug resistance is essential for blocking secondary infections and guiding treatments. In this study, we reported a nucleic acid fluorescent lateral flow assay (NFLFA) to identify A. baumannii and carbapenem-resistant A. baumannii (CRAB) in a rapid and quantitative manner by integrating loop-mediated isothermal amplification (LAMP) and silica–based multilayered quantum dot nanobead tag (Si@MQB). First, a rapid LAMP system was established and optimised to support the effective amplification of two bacterial genes in 35 min. Then, the antibody-modified Si@MQB was introduced to capture the two kinds of amplified DNA sequences and simultaneously detect them on two test lines of a LFA strip, which greatly improved the detection sensitivity and stability of the commonly used AuNP-based nucleic acid LFA. With these strategies, the established LAMP-NFLFA achieved detection limits of 199 CFU/mL and 287 CFU/mL for the RecA (house-keeping gene) and bla_OXA-23 (drug resistance gene) genes, respectively, within 43 min. Furthermore, the assay exhibited good repeatability and specificity for detecting target pathogens in real complex specimens and environments; thus, the proposed assay undoubtedly provides a promising and low-cost tool for the on-site monitoring of nosocomial infections. Full article

(This article belongs to the Section Biosensors and Healthcare)

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12 pages, 3730 KiB

Open AccessArticle

Assessing Phase-Change Materials as Effective Long-Term Biosensors in Limb Prosthetics

by Robert Johnston, Danielle Sell, Goeran Fiedler and Anita Singh

Biosensors 2023, 13(10), 944; https://doi.org/10.3390/bios13100944 - 22 Oct 2023

Viewed by 1631

Abstract

Monitoring and controlling the microclimate at the skin–socket interface of limb prostheses is an important, yet unresolved, clinical problem. Phase-change materials (PCMs) represent a promising biosensor technology that holds the potential to both detect and alter (i.e., stabilize) changes in the temperature of [...] Read more.

Monitoring and controlling the microclimate at the skin–socket interface of limb prostheses is an important, yet unresolved, clinical problem. Phase-change materials (PCMs) represent a promising biosensor technology that holds the potential to both detect and alter (i.e., stabilize) changes in the temperature of a hybrid biological/mechanical system, such as a prosthesis. The biologically inspired sensor capabilities of PCMs can enhance the internal socket conditions and offer improved comfort and suspension while minimizing skin injuries for prosthesis users. This study investigated how prosthetic liners equipped with PCM biosensors affected the long-term outcomes for prosthesis users. In this double-blinded longitudinal crossover study, a cohort of transtibial prosthesis users wore regular conventional liners for six months and PCM liners for another six months. Prosthesis utilization, physical performance, and gait symmetry were studied using Modus StepWatch, the 2-minute walk test, and the TekScan F-Scan gait test, respectively. Measured parameters from these various tests, acquired at multiple timepoints during the study, were compared pairwise between the two liners per individual. While the obtained quantitative data trends, such as the gait symmetry, favored the PCM liners, no statistically significant differences were found between the PCM and conventional gel liners in any of the study parameters. Full article

(This article belongs to the Special Issue Devices and Wearable Devices toward Innovative Applications)

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13 pages, 5518 KiB

Open AccessArticle

Microfluidic Sensor Based on Cell-Imprinted Polymer-Coated Microwires for Conductometric Detection of Bacteria in Water

by Shiva Akhtarian, Ali Doostmohammadi, Daphne-Eleni Archonta, Garrett Kraft, Satinder Kaur Brar and Pouya Rezai

Biosensors 2023, 13(10), 943; https://doi.org/10.3390/bios13100943 - 20 Oct 2023

Cited by 4 | Viewed by 1841

Abstract

The rapid, inexpensive, and on-site detection of bacterial contaminants using highly sensitive and specific microfluidic sensors is attracting substantial attention in water quality monitoring applications. Cell-imprinted polymers (CIPs) have emerged as robust, cost-effective, and versatile recognition materials with selective binding sites for capturing [...] Read more.

The rapid, inexpensive, and on-site detection of bacterial contaminants using highly sensitive and specific microfluidic sensors is attracting substantial attention in water quality monitoring applications. Cell-imprinted polymers (CIPs) have emerged as robust, cost-effective, and versatile recognition materials with selective binding sites for capturing whole bacteria. However, electrochemical transduction of the binding event to a measurable signal within a microfluidic device to develop easy-to-use, compact, portable, durable, and affordable sensors remains a challenge. For this paper, we employed CIP-functionalized microwires (CIP-MWs) with an affinity towards E. coli and integrated them into a low-cost microfluidic sensor to measure the conductometric transduction of CIP–bacteria binding events. The sensor comprised two CIP-MWs suspended perpendicularly to a PDMS microchannel. The inter-wire electrical resistance of the microchannel was measured before, during, and after exposure of CIP-MWs to bacteria. A decline in the inter-wire resistance of the sensor after 30 min of incubation with bacteria was detected. Resistance change normalization and the subsequent analysis of the sensor’s dose-response curve between 0 to 10⁹ CFU/mL bacteria revealed the limits of detection and quantification of 2.1 × 10⁵ CFU/mL and 7.3 × 10⁵ CFU/mL, respectively. The dynamic range of the sensor was 10⁴ to 10⁷ CFU/mL where the bacteria counts were statistically distinguishable from each other. A linear fit in this range resulted in a sensitivity of 7.35 μS per CFU/mL. Experiments using competing Sarcina or Listeria cells showed specificity of the sensor towards the imprinted E. coli cells. The reported CIP-MW-based conductometric microfluidic sensor can provide a cost-effective, durable, portable, and real-time solution for the detection of pathogens in water. Full article

(This article belongs to the Special Issue Microfluidic Biosensing Technologies for Point-of-Care Applications)

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13 pages, 2662 KiB

Open AccessArticle

The Development of Reagentless Amperometric Glucose Biosensor Based on Gold Nanostructures, Prussian Blue and Glucose Oxidase

by Laura Sakalauskiene, Benediktas Brasiunas, Anton Popov, Asta Kausaite-Minkstimiene and Almira Ramanaviciene

Biosensors 2023, 13(10), 942; https://doi.org/10.3390/bios13100942 - 20 Oct 2023

Cited by 4 | Viewed by 2711

Abstract

Precise blood glucose detection plays a crucial role in diagnosing and medicating diabetes, in addition to aiding diabetic patients in effectively managing their condition. In this research, a first-generation reagentless amperometric glucose biosensor was developed by combining the graphite rod (GR) electrode modification [...] Read more.

Precise blood glucose detection plays a crucial role in diagnosing and medicating diabetes, in addition to aiding diabetic patients in effectively managing their condition. In this research, a first-generation reagentless amperometric glucose biosensor was developed by combining the graphite rod (GR) electrode modification by gold nanostructures (AuNS) and Prussian blue (PB) with glucose oxidase (GOx)—an enzyme that can oxidize glucose and produce H₂O₂. Firstly, AuNS was electrochemically deposited on the GR electrode (AuNS/GR), and then PB was electrochemically synthesized on the AuNS/GR electrode (PB/AuNS/GR). Finally, GOx was immobilized over the PB/AuNS nanocomposite with the assistance of Nafion (Nf) (Nf-GOx/PB/AuNS/GR). An application of PB in the design of a glucose biosensor enables an easy electrochemical reduction and, thus, the determination of the H₂O₂ produced during the GOx-catalyzed oxidation of glucose in the sample at a low operation potential of −0.05 V vs. Ag/AgCl/KCl_{3 mol L}⁻¹. In addition, AuNS increased the electrochemically active surface area, improved the GOx immobilization and ensured a higher analytical signal. The developed glucose biosensor based on the Nf-GOx/PB/AuNS/GR electrode exhibited a wide linear range, from 0.025 to 1 mmol L⁻¹ of glucose, with a 0.0088 mmol L⁻¹ limit of detection, good repeatability and high selectivity over electroactive interfering substances. The developed biosensor is convenient for the determination of glucose in the physiological environment. Full article

(This article belongs to the Special Issue Biosensors for the Analysis and Detection of Drug, Food or Disease)

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9 pages, 2580 KiB

Open AccessCommunication

RT-RPA-PfAgo System: A Rapid, Sensitive, and Specific Multiplex Detection Method for Rice-Infecting Viruses

by Yan Liu, Wenqiang Xia, Wei Zhao, Peiying Hao, Zhengliang Wang, Xiaoping Yu, Xuping Shentu and Kai Sun

Biosensors 2023, 13(10), 941; https://doi.org/10.3390/bios13100941 - 20 Oct 2023

Cited by 6 | Viewed by 2362

Abstract

The advancement in CRISPR-Cas biosensors has transmuted the detection of plant viruses owing to their rapid and higher sensitivity. However, false positives and restricted multiplexing capabilities are still the challenges faced by this technology, demanding the exploration of novel methodologies. In this study, [...] Read more.

The advancement in CRISPR-Cas biosensors has transmuted the detection of plant viruses owing to their rapid and higher sensitivity. However, false positives and restricted multiplexing capabilities are still the challenges faced by this technology, demanding the exploration of novel methodologies. In this study, a novel detection system was developed by integrating reverse transcriptome (RT) techniques with recombinase polymerase isothermal amplification (RPA) and Pyrococcus furiosus Argonaute (PfAgo). The RT-RPA-PfAgo system enabled the simultaneous detection of rice ragged stunt virus (RRSV), rice grassy stunt virus (RGSV), and rice black streaked dwarf virus (RBSDV). Identifying targets via guide DNA without being hindered by protospacer adjacent motif sequences is the inherent merit of PfAgo, with the additional advantage of it being simple, cost-effective, and exceptionally sensitive, with detection limits between 3.13 and 5.13 copies/µL, in addition to it effectively differentiating between the three distinct viruses. The field evaluations were also in accordance with RT-PCR methods. The RT-RPA-PfAgo system proved to be a robust, versatile, highly specific, and sensitive method with great potential for practicality in future plant virus diagnostics. Full article

(This article belongs to the Special Issue Biosensing Technologies for Bacteria and Virus Detections)

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12 pages, 12196 KiB

Open AccessArticle

Tapered Fiber Bioprobe Based on U-Shaped Fiber Transmission for Immunoassay

by Xinghong Chen, Lei Xiao, Xuejin Li, Duo Yi, Jinghan Zhang, Hao Yuan, Zhiyao Ning, Xueming Hong and Yuzhi Chen

Biosensors 2023, 13(10), 940; https://doi.org/10.3390/bios13100940 - 20 Oct 2023

Cited by 2 | Viewed by 1774

Abstract

In this paper, a tapered fiber bioprobe based on Mach–Zehnder interference (MZI) is proposed. To retain the highly sensitive straight-tapered fiber MZI sensing structure, we designed a U-shaped transmission fiber structure for the collection of optical sensing signals to achieve a miniature-insert-probe design. [...] Read more.

In this paper, a tapered fiber bioprobe based on Mach–Zehnder interference (MZI) is proposed. To retain the highly sensitive straight-tapered fiber MZI sensing structure, we designed a U-shaped transmission fiber structure for the collection of optical sensing signals to achieve a miniature-insert-probe design. The spectrum responses from the conventional straight-tapered fiber MZI sensor and our proposed sensor were compared and analyzed, and experimental results showed that our proposed sensor not only has the same sensing capability as the straight-tapered fiber sensor, but also has the advantages of being flexible, convenient, and less liquid-consuming, which are attributed to the inserted probe design. The tapered fiber bioprobe obtained a sensitivity of 1611.27 nm/RIU in the refractive index detection range of 1.3326–1.3414. Finally, immunoassays for different concentrations of human immunoglobulin G were achieved with the tapered fiber bioprobe through surface functionalization, and the detection limit was 45 ng/mL. Our tapered fiber bioprobe has the insert-probe advantages of simpleness, convenience, and fast operation. Simultaneously, it is low-cost, highly sensitive, and has a low detection limit, which means it has potential applications in immunoassays and early medical diagnosis. Full article

(This article belongs to the Special Issue Recent Advances in Optical Fiber Biosensor)

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15 pages, 3458 KiB

Open AccessEditor’s ChoiceReview

Quantitative Imaging of Genetically Encoded Fluorescence Lifetime Biosensors

by Cong Quang Vu and Satoshi Arai

Biosensors 2023, 13(10), 939; https://doi.org/10.3390/bios13100939 - 19 Oct 2023

Cited by 5 | Viewed by 4406

Abstract

Genetically encoded fluorescence lifetime biosensors have emerged as powerful tools for quantitative imaging, enabling precise measurement of cellular metabolites, molecular interactions, and dynamic cellular processes. This review provides an overview of the principles, applications, and advancements in quantitative imaging with genetically encoded fluorescence [...] Read more.

Genetically encoded fluorescence lifetime biosensors have emerged as powerful tools for quantitative imaging, enabling precise measurement of cellular metabolites, molecular interactions, and dynamic cellular processes. This review provides an overview of the principles, applications, and advancements in quantitative imaging with genetically encoded fluorescence lifetime biosensors using fluorescence lifetime imaging microscopy (go-FLIM). We highlighted the distinct advantages of fluorescence lifetime-based measurements, including independence from expression levels, excitation power, and focus drift, resulting in robust and reliable measurements compared to intensity-based approaches. Specifically, we focus on two types of go-FLIM, namely Förster resonance energy transfer (FRET)–FLIM and single-fluorescent protein (FP)-based FLIM biosensors, and discuss their unique characteristics and benefits. This review serves as a valuable resource for researchers interested in leveraging fluorescence lifetime imaging to study molecular interactions and cellular metabolism with high precision and accuracy. Full article

(This article belongs to the Special Issue Probes for Living Cell Detection)

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17 pages, 3894 KiB

Open AccessArticle

Analytical Validation of a Spiral Microfluidic Chip with Hydrofoil-Shaped Pillars for the Enrichment of Circulating Tumor Cells

by Begum Sen-Dogan, Mehmet Alper Demir, Buket Sahin, Ender Yildirim, Gizem Karayalcin, Sebnem Sahin, Ege Mutlu, Taylan Berkin Toral, Ebru Ozgur, Ozge Zorlu and Haluk Kulah

Biosensors 2023, 13(10), 938; https://doi.org/10.3390/bios13100938 - 19 Oct 2023

Cited by 1 | Viewed by 2215

Abstract

The isolation of circulating tumor cells (CTCs) from peripheral blood with high efficiency remains a challenge hindering the utilization of CTC enrichment methods in clinical practice. Here, we propose a microfluidic channel design for the size-based hydrodynamic enrichment of CTCs from blood in [...] Read more.

The isolation of circulating tumor cells (CTCs) from peripheral blood with high efficiency remains a challenge hindering the utilization of CTC enrichment methods in clinical practice. Here, we propose a microfluidic channel design for the size-based hydrodynamic enrichment of CTCs from blood in an epitope-independent and high-throughput manner. The microfluidic channel comprises a spiral-shaped part followed by a widening part, incorporating successive streamlined pillars, that improves the enrichment efficiency. The design was tested against two benchmark designs, a spiral microfluidic channel and a spiral microfluidic channel followed by a widening channel without the hydrofoils, by processing 5 mL of healthy blood samples spiked with 100 MCF-7 cells. The results proved that the design with hydrofoil-shaped pillars perform significantly better in terms of recovery (recovery rate of 67.9% compared to 23.6% in spiral and 56.7% in spiral with widening section), at a cost of slightly lower white blood cell (WBC) depletion (depletion rate of 94.2% compared to 98.6% in spiral and 94.2% in spiral with widening section), at 1500 µL/min flow rate. For analytical validation, the design was further tested with A549, SKOV-3, and BT-474 cell lines, yielding recovery rates of 62.3 ± 8.4%, 71.0 ± 6.5%, and 82.9 ± 9.9%, respectively. The results are consistent with the size and deformability variation in the respective cell lines, where the increasing size and decreasing deformability affect the recovery rate in a positive manner. The analysis before and after the microfluidic chip process showed that the process does not affect cell viability. Full article

(This article belongs to the Special Issue Microfluidics for Biomedical Applications (2nd Edition))

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Graphical abstract

3 pages, 170 KiB

Open AccessEditorial

Special Issue “Synthetic Biology for Biosensing in Health and Environmental Applications”

by Baojun Wang and Cheemeng Tan

Biosensors 2023, 13(10), 937; https://doi.org/10.3390/bios13100937 - 19 Oct 2023

Viewed by 1958

Abstract

Biosensors are analytical devices that utilize biological sensing elements, such as enzymes, antibodies, nucleic acids, or cells, to detect a given analyte [...] Full article

(This article belongs to the Special Issue Synthetic Biology for Biosensing in Health and Environmental Applications)

17 pages, 7074 KiB

Open AccessArticle

Ruthenium-Anchored Carbon Sphere-Customized Sensor for the Selective Amperometric Detection of Melatonin

by Sivaguru Jayaraman, Thenmozhi Rajarathinam, Hyeon-Geun Jang, Dinakaran Thirumalai, Jaewon Lee, Hyun-Jong Paik and Seung-Cheol Chang

Biosensors 2023, 13(10), 936; https://doi.org/10.3390/bios13100936 - 18 Oct 2023

Cited by 6 | Viewed by 2027

Abstract

Melatonin (MT), a pineal gland hormone, regulates the sleep/wake cycle and is a potential biomarker for neurodegenerative disorders, depression, hypertension, and several cancers, including prostate cancer and hepatocarcinoma. The amperometric detection of MT was achieved using a sensor customized with ruthenium-incorporated carbon spheres [...] Read more.

Melatonin (MT), a pineal gland hormone, regulates the sleep/wake cycle and is a potential biomarker for neurodegenerative disorders, depression, hypertension, and several cancers, including prostate cancer and hepatocarcinoma. The amperometric detection of MT was achieved using a sensor customized with ruthenium-incorporated carbon spheres (Ru–CS), possessing C- and O-rich catalytically active Ru surfaces. The non-covalent interactions and ion–molecule adducts between Ru and CS favor the formation of heterojunctions at the sensor–analyte interface, thus accelerating the reactions towards MT. The Ru–CS/Screen-printed carbon electrode (SPCE) sensor demonstrated the outstanding electrocatalytic oxidation of MT owing to its high surface area and heterogeneous rate constants and afforded a lower detection limit (0.27 μM), high sensitivity (0.85 μA μM ⁻¹ cm⁻²), and excellent selectivity for MT with the co-existence of crucial neurotransmitters, including norepinephrine, epinephrine, dopamine, and serotonin. High concentrations of active biomolecules, such as ascorbic acid and tyrosine, did not interfere with MT detection. The practical feasibility of the sensor for MT detection in pharmaceutical samples was demonstrated, comparable to the data provided on the product labels. The developed amperometric sensor is highly suitable for the quality control of medicines because of its low cost, simplicity, small sample size, speed of analysis, and potential for automation. Full article

(This article belongs to the Special Issue Polymer-Metal-Carbon-Based Hybrid Materials for Biosensors)

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21 pages, 1709 KiB

Open AccessReview

Microfluidic Device-Based Virus Detection and Quantification in Future Diagnostic Research: Lessons from the COVID-19 Pandemic

by Andres Escobar, Alex Diab-Liu, Kamaya Bosland and Chang-qing Xu

Biosensors 2023, 13(10), 935; https://doi.org/10.3390/bios13100935 - 18 Oct 2023

Cited by 1 | Viewed by 2975

Abstract

The global economic and healthcare crises experienced over the past three years, as a result of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has significantly impacted the commonplace habits of humans around the world. SARS-CoV-2, the virus responsible for the coronavirus 2019 (COVID-19) [...] Read more.

The global economic and healthcare crises experienced over the past three years, as a result of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has significantly impacted the commonplace habits of humans around the world. SARS-CoV-2, the virus responsible for the coronavirus 2019 (COVID-19) phenomenon, has contributed to the deaths of millions of people around the world. The potential diagnostic applications of microfluidic devices have previously been demonstrated to effectively detect and quasi-quantify several different well-known viruses such as human immunodeficiency virus (HIV), influenza, and SARS-CoV-2. As a result, microfluidics has been further explored as a potential alternative to our currently available rapid tests for highly virulent diseases to better combat and manage future potential outbreaks. The outbreak management during COVID-19 was initially hindered, in part, by the lack of available quantitative rapid tests capable of confirming a person’s active infectiousness status. Therefore, this review will explore the use of microfluidic technology, and more specifically RNA-based virus detection methods, as an integral part of improved diagnostic capabilities and will present methods for carrying the lessons learned from COVID-19 forward, toward improved diagnostic outcomes for future pandemic-level threats. This review will first explore the context of the COVID-19 pandemic and how diagnostic technology was shown to have required even greater advancements to keep pace with the transmission of such a highly infectious virus. Secondly, the historical significance of integrating microfluidic technology in diagnostics and how the different types of genetic-based detection methods may vary in their potential practical applications. Lastly, the review will summarize the past, present, and future potential of RNA-based virus detection/diagnosis and how it might be used to better prepare for a future pandemic. Full article

(This article belongs to the Special Issue Emerging Point-of-Care Biosensors and Their Applications)

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13 pages, 3538 KiB

Open AccessArticle

Wearable Electrochemical Glove-Based Analytical Device (eGAD) for the Detection of Methamphetamine Employing Silver Nanoparticles

by Nigar Anzar, Shariq Suleman, Yashda Singh, Suhel Parvez, Manika Khanuja, Roberto Pilloton and Jagriti Narang

Biosensors 2023, 13(10), 934; https://doi.org/10.3390/bios13100934 - 18 Oct 2023

Cited by 1 | Viewed by 2203

Abstract

Illicit drug misuse has become a widespread issue that requires continuous drug monitoring and diagnosis. Wearable electrochemical drug detection devices possess the potential to function as potent screening instruments in the possession of law enforcement personnel, aiding in the fight against drug trafficking [...] Read more.

Illicit drug misuse has become a widespread issue that requires continuous drug monitoring and diagnosis. Wearable electrochemical drug detection devices possess the potential to function as potent screening instruments in the possession of law enforcement personnel, aiding in the fight against drug trafficking and facilitating forensic investigations conducted on site. These wearable sensors are promising alternatives to traditional detection methods. In this study, we present a novel wearable electrochemical glove-based analytical device (eGAD) designed especially for detecting the club drug, methamphetamine. To develop this sensor, we immobilized meth aptamer onto silver nanoparticle (AgNPs)-modified electrodes that were printed onto latex gloves. The characteristics of AgNPs, including their shape, size and purity were analysed using FTIR, SEM and UV vis spectrometry, confirming the successful synthesis. The developed sensor shows a 0.1 µg/mL limit of detection and 0.3 µg/mL limit of quantification with a linear concentration range of about 0.01–5 µg/mL and recovery percentages of approximately 102 and 103%, respectively. To demonstrate its applicability, we tested the developed wearable sensor by spiking various alcoholic and non-alcoholic drink samples. We found that the sensor remains effective for 60 days, making it a practical option with a reasonable shelf-life. The developed sensor offers several advantages, including its affordability, ease of handling and high sensitivity and selectivity. Its portable nature makes it an ideal tool for rapid detection of METH in beverages too. Full article

(This article belongs to the Special Issue Current Accuracy and Advances in Wearable Sensors and Biosensors for Physiological Signals Measurement)

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28 pages, 4284 KiB

Open AccessReview

Smart Contact Lenses—A Step towards Non-Invasive Continuous Eye Health Monitoring

by Nikolay L. Kazanskiy, Svetlana N. Khonina and Muhammad A. Butt

Biosensors 2023, 13(10), 933; https://doi.org/10.3390/bios13100933 - 18 Oct 2023

Cited by 9 | Viewed by 5072

Abstract

According to the age-old adage, while eyes are often considered the gateway to the soul, they might also provide insights into a more pragmatic aspect of our health: blood sugar levels. This potential breakthrough could be realized through the development of smart contact [...] Read more.

According to the age-old adage, while eyes are often considered the gateway to the soul, they might also provide insights into a more pragmatic aspect of our health: blood sugar levels. This potential breakthrough could be realized through the development of smart contact lenses (SCLs). Although contact lenses were first developed for eyesight correction, new uses have recently become available. In the near future, it might be possible to monitor a variety of ocular and systemic disorders using contact lens sensors. Within the realm of glaucoma, SCLs present a novel prospect, offering a potentially superior avenue compared to traditional management techniques. These lenses introduce the possibility of non-invasive and continuous monitoring of intraocular pressure (IOP) while also enabling the personalized administration of medication as and when needed. This convergence holds great promise for advancing glaucoma care. In this review, recent developments in SCLs, including their potential applications, such as IOP and glucose monitoring, are briefly discussed. Full article

(This article belongs to the Section Wearable Biosensors)

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12 pages, 3092 KiB

Open AccessArticle

Development of a Novel H-Shaped Electrochemical Aptasensor for Detection of Hg²⁺ Based on Graphene Aerogels–Au Nanoparticles Composite

by Gang Peng, Mengxue Guo, Yuting Liu, Han Yang, Zuorui Wen and Xiaojun Chen

Biosensors 2023, 13(10), 932; https://doi.org/10.3390/bios13100932 - 18 Oct 2023

Viewed by 1673

Abstract

Hg²⁺, a highly toxic heavy metal, poses significant environmental and health risks, necessitating rapid detection methods. In this study, we employed an electrochemical aptasensor for rapid and sensitive detection of Hg²⁺ based on DNA strands (H2 and H3) immobilized graphene [...] Read more.

Hg²⁺, a highly toxic heavy metal, poses significant environmental and health risks, necessitating rapid detection methods. In this study, we employed an electrochemical aptasensor for rapid and sensitive detection of Hg²⁺ based on DNA strands (H2 and H3) immobilized graphene aerogels-Au nanoparticles (GAs-AuNPs) hybrid recognition interface and exonuclease III (Exo III)-mediated cyclic amplification. Firstly, Gas-AuNPs were modified on the surface of the ITO electrode to form a sensing interface to increase DNA loading and accelerate electron transfer. Then, DNA helper was generated with the addition of Hg²⁺ via Exo III-mediated cycling. Finally, the hairpin structures of H2 and H3 were opened with the DNA helper, and then the methylene blue (MB) functionalized DNA (A1 and A2) combined with the H2 and H3 to form an H-shaped structure. The current response of MB as an electrochemical probe was proportional to the concentration of Hg²⁺. Under optimal conditions, the aptasensor showed excellent performance for Hg²⁺, achieving a linear range from 1 fM to 10 nM and a detection limit of 0.16 fM. Furthermore, the aptasensor was used to detect Hg²⁺ in spiked milk samples, achieving a high recovery rate and demonstrating promising application prospects. Full article

(This article belongs to the Special Issue Recent Advances in Aptasensors for Clinical, Environmental and Food Safety Analysis)

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16 pages, 2317 KiB

Open AccessArticle

Electrochemical DNA Sensor for Valrubicin Detection Based on Poly(Azure C) Films Deposited from Deep Eutectic Solvent

by Anna Porfireva, Ekaterina Begisheva, Vladimir Evtugyn and Gennady Evtugyn

Biosensors 2023, 13(10), 931; https://doi.org/10.3390/bios13100931 - 18 Oct 2023

Cited by 3 | Viewed by 1857

Abstract

A novel electrochemical DNA sensor was developed for the detection of the anthracycline drug, valrubicin, on the base of poly(Azure C) electropolymerized from the deep eutectic solvent reline and covered with adsorbed DNA from calf thymus. Biosensor assembling was performed by multiple scanning [...] Read more.

A novel electrochemical DNA sensor was developed for the detection of the anthracycline drug, valrubicin, on the base of poly(Azure C) electropolymerized from the deep eutectic solvent reline and covered with adsorbed DNA from calf thymus. Biosensor assembling was performed by multiple scanning of the potential in one drop (100 µL) of the dye dissolved in reline and placed on the surface of a screen-printed carbon electrode. Stabilization of the coating was achieved by its polarization in the phosphate buffer. The electrochemical characteristics of the electron transfer were determined and compared with a similar coating obtained from phosphate buffer. The use of deep eutectic solvent made it possible to increase the monomer concentration and avoid using organic solvents on the stage of electrode modification. After the contact of the DNA sensor with valrubicin, two signals related to the intrinsic redox activity of the coating and the drug redox conversion were found on voltammogram. Their synchronous changes with the analyte concentration increased the reliability of the detection. In the square-wave mode, the DNA sensor made it possible to determine from 3 µM to 1 mM (limit of detection, 1 µM) in optimal conditions. The DNA sensor was successfully tested in the voltammetric determination of valrubicin in spiked artificial urine, Ringer-Locke solution mimicking plasma electrolytes and biological samples (urine and saliva) with a recovery of 90–110%. After further testing on clinical samples, it can find application in the pharmacokinetics studies and screening of new drugs’ interaction with DNA. Full article

(This article belongs to the Special Issue Recent Progress in DNA Nanostructure-Based Electrochemical Biosensors)

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19 pages, 6872 KiB

Open AccessReview

Application and Development of EEG Acquisition and Feedback Technology: A Review

by Yong Qin, Yanpeng Zhang, Yan Zhang, Sheng Liu and Xiaogang Guo

Biosensors 2023, 13(10), 930; https://doi.org/10.3390/bios13100930 - 17 Oct 2023

Cited by 7 | Viewed by 6974

Abstract

This review focuses on electroencephalogram (EEG) acquisition and feedback technology and its core elements, including the composition and principles of the acquisition devices, a wide range of applications, and commonly used EEG signal classification algorithms. First, we describe the construction of EEG acquisition [...] Read more.

This review focuses on electroencephalogram (EEG) acquisition and feedback technology and its core elements, including the composition and principles of the acquisition devices, a wide range of applications, and commonly used EEG signal classification algorithms. First, we describe the construction of EEG acquisition and feedback devices encompassing EEG electrodes, signal processing, and control and feedback systems, which collaborate to measure faint EEG signals from the scalp, convert them into interpretable data, and accomplish practical applications using control feedback systems. Subsequently, we examine the diverse applications of EEG acquisition and feedback across various domains. In the medical field, EEG signals are employed for epilepsy diagnosis, brain injury monitoring, and sleep disorder research. EEG acquisition has revealed associations between brain functionality, cognition, and emotions, providing essential insights for psychologists and neuroscientists. Brain–computer interface technology utilizes EEG signals for human–computer interaction, driving innovation in the medical, engineering, and rehabilitation domains. Finally, we introduce commonly used EEG signal classification algorithms. These classification tasks can identify different cognitive states, emotional states, brain disorders, and brain–computer interface control and promote further development and application of EEG technology. In conclusion, EEG acquisition technology can deepen the understanding of EEG signals while simultaneously promoting developments across multiple domains, such as medicine, science, and engineering. Full article

(This article belongs to the Section Biosensors and Healthcare)

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14 pages, 3037 KiB

Open AccessArticle

Peptide-Coated Bacteriorhodopsin-Based Photoelectric Biosensor for Detecting Rheumatoid Arthritis

by Hsiu-Mei Chen, Yi-Hsuan Tsai, Chien-Yi Hsu, Yong-Yi Wang, Cheng-En Hsieh, Jin-Hua Chen, Yu-Sheng Chang and Ching-Yu Lin

Biosensors 2023, 13(10), 929; https://doi.org/10.3390/bios13100929 - 16 Oct 2023

Cited by 4 | Viewed by 4756

Abstract

An effective early diagnosis is important for rheumatoid arthritis (RA) management. This study reveals a novel RA detection method using bacteriorhodopsin as a photoelectric transducer, a light-driven proton pump in purple membranes (PMs). It was devised by covalently conjugating a PM monolayer-coated electrode [...] Read more.

An effective early diagnosis is important for rheumatoid arthritis (RA) management. This study reveals a novel RA detection method using bacteriorhodopsin as a photoelectric transducer, a light-driven proton pump in purple membranes (PMs). It was devised by covalently conjugating a PM monolayer-coated electrode with a citrullinated-inter-alpha-trypsin inhibitor heavy chain 3 (ITIH3)^542–556 peptide that recognizes the serum RA-associated autoantibodies. The direct serum coating decreased the photocurrents in the biosensor, with the reduction in the photocurrent caused by coating with an RA-patient serum that is significantly larger than that with a healthy-control serum (38.1% vs. 20.2%). The difference in the reduction in the photocurrent between those two serum groups widened after the serum-coated biosensor was further labeled with gold nanoparticle (AuNP)-conjugated anti-IgA (anti-IgA-AuNP) (53.6% vs. 30.6%). Both atomic force microscopic (AFM) and Raman analyses confirmed the sequential peptide, serum, and anti-IgA-AuNP coatings on the PM-coated substrates. The reductions in the photocurrent measured in both the serum and anti-IgA-AuNPs coating steps correlated well with the results using commercial enzyme-linked immunosorbent assay kits (Spearman rho = 0.805 and 0.787, respectively), with both a sensitivity and specificity close to 100% in both steps. It was shown that an RA diagnosis can be performed in either a single- or two-step mode using the developed biosensor. Full article

(This article belongs to the Special Issue Immunoassays and Biosensing)

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4 pages, 187 KiB

Open AccessEditorial

Smart and Multifunctional Nanomaterials and Applications for Food Safety

by Long Wu

Biosensors 2023, 13(10), 928; https://doi.org/10.3390/bios13100928 - 16 Oct 2023

Viewed by 1629

Abstract

Due to growing concerns about food safety and public health, the contaminants or residues of various harmful substances in food have received much attention in recent years [...] Full article

(This article belongs to the Special Issue Smart and Multifunctional Nanomaterials and Applications for Food Safety)

13 pages, 6058 KiB

Open AccessCommunication

Surface-Enhanced Raman Scattering Active Core-Shell Ag NPs@Carbon Dots with Enzyme-Mimicking Activities for Label-Free Measurement Cholesterol

by Jian Ju, Lin Li, Bei Li, Sagar Regmi, Tingting Wang, Jiao Xu, Chaojie Li and Shixing Tang

Biosensors 2023, 13(10), 927; https://doi.org/10.3390/bios13100927 - 16 Oct 2023

Viewed by 2037

Abstract

Serological-sensitive testing of cholesterol holds significant value in the fields of healthcare and clinical diagnosis. This study reports on the preparation of peroxidase-mimicking nanozymes through the wrapping of N, S-doped carbon dots (DCDs) on the surface of silver nanoparticles (Ag NPs@DCD). The shell–core [...] Read more.

Serological-sensitive testing of cholesterol holds significant value in the fields of healthcare and clinical diagnosis. This study reports on the preparation of peroxidase-mimicking nanozymes through the wrapping of N, S-doped carbon dots (DCDs) on the surface of silver nanoparticles (Ag NPs@DCD). The shell–core structure of Ag NPs@DCD displays peroxidase-mimicking capability, with the potential to catalyze inactive Raman probe molecules into the Raman reporters. Furthermore, a “shell-isolated nanoparticles-enhanced Raman spectroscopy” structure exhibited an enhanced Raman signal of reporter molecules. Ag NPs@DCD were utilized to create a label-free SERS sensing system for high-performance detection of cholesterol in serum samples. These results demonstrate the potential of the novel nanozyme-based SERS approach for clinical diagnosis. Full article

(This article belongs to the Special Issue Recent Advance in Biosensors and Its Applications in Point-of-Care Molecular Diagnostics (POC-MDx))

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27 pages, 4314 KiB

Open AccessReview

Current Status and Emerging Trends in Colorectal Cancer Screening and Diagnostics

by Shreya Singh Beniwal, Paula Lamo, Ajeet Kaushik, Dionisio Lorenzo Lorenzo-Villegas, Yuguang Liu and ArunSundar MohanaSundaram

Biosensors 2023, 13(10), 926; https://doi.org/10.3390/bios13100926 - 13 Oct 2023

Cited by 13 | Viewed by 5883

Abstract

Colorectal cancer (CRC) is a prevalent and potentially fatal disease categorized based on its high incidences and mortality rates, which raised the need for effective diagnostic strategies for the early detection and management of CRC. While there are several conventional cancer diagnostics available, [...] Read more.

Colorectal cancer (CRC) is a prevalent and potentially fatal disease categorized based on its high incidences and mortality rates, which raised the need for effective diagnostic strategies for the early detection and management of CRC. While there are several conventional cancer diagnostics available, they have certain limitations that hinder their effectiveness. Significant research efforts are currently being dedicated to elucidating novel methodologies that aim at comprehending the intricate molecular mechanism that underlies CRC. Recently, microfluidic diagnostics have emerged as a pivotal solution, offering non-invasive approaches to real-time monitoring of disease progression and treatment response. Microfluidic devices enable the integration of multiple sample preparation steps into a single platform, which speeds up processing and improves sensitivity. Such advancements in diagnostic technologies hold immense promise for revolutionizing the field of CRC diagnosis and enabling efficient detection and monitoring strategies. This article elucidates several of the latest developments in microfluidic technology for CRC diagnostics. In addition to the advancements in microfluidic technology for CRC diagnostics, the integration of artificial intelligence (AI) holds great promise for further enhancing diagnostic capabilities. Advancements in microfluidic systems and AI-driven approaches can revolutionize colorectal cancer diagnostics, offering accurate, efficient, and personalized strategies to improve patient outcomes and transform cancer management. Full article

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

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11 pages, 12866 KiB

Open AccessArticle

Functionalized-Graphene Field Effect Transistor-Based Biosensor for Ultrasensitive and Label-Free Detection of β-Galactosidase Produced by Escherichia coli

by Shanhong Wei, Yanzhi Dou, Shiping Song and Tie Li

Biosensors 2023, 13(10), 925; https://doi.org/10.3390/bios13100925 - 12 Oct 2023

Viewed by 1982

Abstract

The detection of β-galactosidase (β-gal) activity produced by Escherichia coli (E. coli) can quickly analyze the pollution degree of seawater bodies in bathing and fishing grounds to avoid large-scale outbreaks of water pollution. Here, a functionalized biosensor based on graphene-based field [...] Read more.

The detection of β-galactosidase (β-gal) activity produced by Escherichia coli (E. coli) can quickly analyze the pollution degree of seawater bodies in bathing and fishing grounds to avoid large-scale outbreaks of water pollution. Here, a functionalized biosensor based on graphene-based field effect transistor (GFET) modified with heat-denatured casein was developed for the ultrasensitive and label-free detection of the β-gal produced by E. coli in real water samples. The heat-denatured casein coated on the graphene surface, as a probe linker and blocker, plays an important role in fabricating GEFT biosensor. The GFET biosensor response to the β-gal produced by E. coli has a wide concentration dynamic range spanning nine orders of magnitude, in a concentration range of 1 fg·mL⁻¹–100 ng·mL⁻¹, with a limit of detection (LOD) 0.187 fg·mL⁻¹ (1.61 aM). In addition to its attomole sensitivity, the GFET biosensor selectively recognized the β-gal in the water sample and showed good selectivity. Importantly, the detection process of the β-gal produced by E. coli can be completed by a straightforward one-step specific immune recognition reaction. These results demonstrated the usefulness of the approach, meeting environmental monitoring requirements for future use. Full article

(This article belongs to the Special Issue Electrochemical Sensors and Biosensors for Environmental, Health, and Food Safety Applications)

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14 pages, 1789 KiB

Open AccessArticle

Development of an Electrochemical Sensor for SARS-CoV-2 Detection Based on Loop-Mediated Isothermal Amplification

by Ane Rivas-Macho, Unai Eletxigerra, Ruth Diez-Ahedo, Ángela Barros, Santos Merino, Felipe Goñi-de-Cerio and Garbiñe Olabarria

Biosensors 2023, 13(10), 924; https://doi.org/10.3390/bios13100924 - 11 Oct 2023

Cited by 3 | Viewed by 1813

Abstract

The pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused more than 6 million deaths all over the world, demonstrating the need for a simple, fast and cost-effective point-of-care (POC) test for the detection of the virus. In this work, [...] Read more.

The pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused more than 6 million deaths all over the world, demonstrating the need for a simple, fast and cost-effective point-of-care (POC) test for the detection of the virus. In this work, we developed an electrochemical sensor for SARS-CoV-2 virus detection on clinical samples based on loop-mediated isothermal amplification (LAMP). With the development of this novel sensor, the time of each measurement is significantly reduced by avoiding the DNA extraction step and replacing it with inactivation of the sample by heating it at 95 °C for 10 min. To make the reaction compatible with the sample pre-treatment, an RNase inhibitor was added directly to the premix. The LAMP product was measured in a novel, easy-to-use manufactured sensor containing a custom-made screen-printed carbon electrode. Electrochemical detection was performed with a portable potentiostat, and methylene blue was used as the redox-transducing molecule. The developed sensor achieved a limit of detection of 62 viral copies and was 100% specific for the detection of the SARS-CoV-2 virus. The performance of the electrochemical sensor was validated with nasopharyngeal samples, obtaining a sensibility and specificity of 100% compared to the gold standard RT-PCR method. Full article

(This article belongs to the Special Issue Advances in Amplification Methods for Biosensors (Volume II))

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10 pages, 1527 KiB

Open AccessCommunication

Photoacoustic Chemical Imaging Sodium Nano-Sensor Utilizing a Solvatochromic Dye Transducer for In Vivo Application

by Jeff Folz, Jacalyn H. Wasserman, Janggun Jo, Xueding Wang and Raoul Kopelman

Biosensors 2023, 13(10), 923; https://doi.org/10.3390/bios13100923 - 11 Oct 2023

Viewed by 1605

Abstract

Sodium has many vital and diverse roles in the human body, including maintaining the cellular pH, generating action potential, and regulating osmotic pressure. In cancer, sodium dysregulation has been correlated with tumor growth, metastasis, and immune cell inhibition. However, most in vivo sodium [...] Read more.

Sodium has many vital and diverse roles in the human body, including maintaining the cellular pH, generating action potential, and regulating osmotic pressure. In cancer, sodium dysregulation has been correlated with tumor growth, metastasis, and immune cell inhibition. However, most in vivo sodium measurements are performed via Na²³ NMR, which is handicapped by slow acquisition times, a low spatial resolution (in mm), and low signal-to-noise ratios. We present here a plasticizer-free, ionophore-based sodium-sensing nanoparticle that utilizes a solvatochromic dye transducer to circumvent the pH cross-sensitivity of most previously reported sodium nano-sensors. We demonstrate that this nano-sensor is non-toxic, boasts a 200 μM detection limit, and is over 1000 times more selective for sodium than potassium. Further, the in vitro photoacoustic calibration curve presented demonstrates the potential of this nano-sensor for performing the in vivo chemical imaging of sodium over the entire physiologically relevant concentration range. Full article

(This article belongs to the Special Issue Advances in Bioimaging and Biosensing)

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24 pages, 2232 KiB

Open AccessReview

Emerging Applications of Nanobiosensors in Pathogen Detection in Water and Food

by Hiram Martin Valenzuela-Amaro, Alberto Aguayo-Acosta, Edgar Ricardo Meléndez-Sánchez, Orlando de la Rosa, Perla Guadalupe Vázquez-Ortega, Mariel Araceli Oyervides-Muñoz, Juan Eduardo Sosa-Hernández and Roberto Parra-Saldívar

Biosensors 2023, 13(10), 922; https://doi.org/10.3390/bios13100922 - 11 Oct 2023

Cited by 12 | Viewed by 4982

Abstract

Food and waterborne illnesses are still a major concern in health and food safety areas. Every year, almost 0.42 million and 2.2 million deaths related to food and waterborne illness are reported worldwide, respectively. In foodborne pathogens, bacteria such as Salmonella, Shiga-toxin [...] Read more.

Food and waterborne illnesses are still a major concern in health and food safety areas. Every year, almost 0.42 million and 2.2 million deaths related to food and waterborne illness are reported worldwide, respectively. In foodborne pathogens, bacteria such as Salmonella, Shiga-toxin producer Escherichia coli, Campylobacter, and Listeria monocytogenes are considered to be high-concern pathogens. High-concern waterborne pathogens are Vibrio cholerae, leptospirosis, Schistosoma mansoni, and Schistosima japonicum, among others. Despite the major efforts of food and water quality control to monitor the presence of these pathogens of concern in these kinds of sources, foodborne and waterborne illness occurrence is still high globally. For these reasons, the development of novel and faster pathogen-detection methods applicable to real-time surveillance strategies are required. Methods based on biosensor devices have emerged as novel tools for faster detection of food and water pathogens, in contrast to traditional methods that are usually time-consuming and are unsuitable for large-scale monitoring. Biosensor devices can be summarized as devices that use biochemical reactions with a biorecognition section (isolated enzymes, antibodies, tissues, genetic materials, or aptamers) to detect pathogens. In most cases, biosensors are based on the correlation of electrical, thermal, or optical signals in the presence of pathogen biomarkers. The application of nano and molecular technologies allows the identification of pathogens in a faster and high-sensibility manner, at extremely low-pathogen concentrations. In fact, the integration of gold, silver, iron, and magnetic nanoparticles (NP) in biosensors has demonstrated an improvement in their detection functionality. The present review summarizes the principal application of nanomaterials and biosensor-based devices for the detection of pathogens in food and water samples. Additionally, it highlights the improvement of biosensor devices through nanomaterials. Nanomaterials offer unique advantages for pathogen detection. The nanoscale and high specific surface area allows for more effective interaction with pathogenic agents, enhancing the sensitivity and selectivity of the biosensors. Finally, biosensors’ capability to functionalize with specific molecules such as antibodies or nucleic acids facilitates the specific detection of the target pathogens. Full article

(This article belongs to the Special Issue Novel Nanomaterials and Nanotechnology: From Fabrication Methods and Improvement Strategies to Applications in Biosensing and Biomedicine)

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17 pages, 2075 KiB

Open AccessArticle

Immunotechniques for the Group Determination of Macrolide Antibiotics Traces in the Environment Using a Volume-Mediated Sensitivity Enhancement Strategy

by Maksim A. Burkin, Anna N. Tevyashova, Elena N. Bychkova, Artem O. Melekhin and Inna A. Galvidis

Biosensors 2023, 13(10), 921; https://doi.org/10.3390/bios13100921 - 10 Oct 2023

Cited by 1 | Viewed by 1645

Abstract

Macrolide antibiotics, which are effective antimicrobial agents, are intensively used in human and veterinary medicine, as well as in agriculture. Consequently, they are found all over the world as environmental pollutants, causing harm to sensitive ecological communities and provoking a selection of resistant [...] Read more.

Macrolide antibiotics, which are effective antimicrobial agents, are intensively used in human and veterinary medicine, as well as in agriculture. Consequently, they are found all over the world as environmental pollutants, causing harm to sensitive ecological communities and provoking a selection of resistant forms. A novel azithromycin derivative, which was used as hapten conjugate, ensured the group immunorecognition of six major macrolide representatives (105–41%), namely erythromycin, erythromycin ethylsuccinate, clarithromycin, roxithromycin, azithromycin, and dirithromycin in a competitive immunoassay based on anti-clarithromycin antibodies. The heterologous hapten-based ELISA format resulted in a 5-fold increase in sensitivity, with an IC₅₀ value of 0.04 ng/mL for erythromycin. In this study, we proposed an underexploited strategy in an immunoassay field to significantly improve the detectability of analytes in environmental samples. Unlike most approaches, it does not require special enhancers/amplifiers or additional concentration/extraction procedures; instead, it involves analyzing a larger volume of test samples. A gradual volume increase in the samples (from 0.025 to 10 mL) analyzed using a direct competitive ELISA, immunobeads, and immunofiltration assay formats based on the same reagents resulted in a significant improvement (more than 50-fold) in assay sensitivity and detection limit up to 5 and 1 pg/mL, respectively. The suitability of the test for detecting the macrolide contamination of natural water was confirmed by the recovery of macrolides from spiked blank samples (71.7–141.3%). During 2022–2023, a series of natural water samples from Lake Onega and its influents near Petrozavodsk were analyzed, using both the developed immunoassay and HPLC-MS/MS. The results revealed no contamination of macrolide antibiotic. Full article

(This article belongs to the Special Issue Novel Biosensors for Food Safety and Environmental Monitoring)

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13 pages, 2647 KiB

Open AccessArticle

Functionalized GD2 Electrochemical Immunosensor to Diagnose Minimum Residual Disease of Bone Marrow in Neuroblastoma Effectively

by Chong Chen, Chang Hu, Baixun He, Yongchang Bai, Feng He, Shuang Li and Cherie S. Tan

Biosensors 2023, 13(10), 920; https://doi.org/10.3390/bios13100920 - 10 Oct 2023

Viewed by 1726

Abstract

Neuroblastoma (NB) is known as the “king of childhood tumors” due to its highly metastatic, recurrence-prone, and difficult-to-treat characteristics. International Neuroblastoma Risk Grading Group (INRG) has recommended GD2, a disialoganglioside expressed on neuroectodermal tumor cells, as the target for detecting minimal residual disease [...] Read more.

Neuroblastoma (NB) is known as the “king of childhood tumors” due to its highly metastatic, recurrence-prone, and difficult-to-treat characteristics. International Neuroblastoma Risk Grading Group (INRG) has recommended GD2, a disialoganglioside expressed on neuroectodermal tumor cells, as the target for detecting minimal residual disease in bone marrow metastases of high-risk neuroblastoma in children. Therefore, accurately identifying GD2-positive cells is crucial for diagnosing children with high-risk NB. Here, we designed a graphene/AuNP/GD2 Ab-functionalized electrochemical biosensor for GD2 detection. A three-electrode system was processed using a screen-printed technique with a working electrode of indium tin oxide, a counter electrode of carbon, and a reference electrode of silver/silver chloride. Graphene/AuNPs were modified on the indium tin oxide electrode using chronoamperometric scans, and then, the GD2 antibody was modified on the biosensor by electrostatic adsorption to achieve sensitive and specific detection of GD2-positive cells in bone marrow fluid. The results showed that a graphene/AuNP/GD2 Ab-functionalized electrochemical biosensor achieved GD2-positive cell detection in the range of 10² cells/mL~10⁵ cells/mL by differential pulse voltammetry. Bone marrow fluid samples from 12 children with high-risk NB were retained for testing on our biosensor and showed 100% compliance with the clinical application of the gold-standard immunocytochemical staining technique for detecting GD2-positive cells qualitatively. The GD2-based electrochemical assay can accurately detect children with high-risk NB, providing a rapidly quantitative basis for clinical diagnosis and treatment. Full article

(This article belongs to the Special Issue Electrochemical (Bio-) Sensors in Biological Applications—2nd Edition)

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11 pages, 3810 KiB

Open AccessArticle

A Nanozymatic-Mediated Smartphone Colorimetric Sensing Platform for the Detection of Dimethyl Phthalate (DMP) and Dibutyl Phthalate (DBP)

by Wenhui Li, Xuecheng Zhang, Haojie Zhang, Cheng Zhang, Yingjie Chen, Cong Li, Yonghong Hu, Xiaoping Yu, Biao Zhang and Xiaodong Lin

Biosensors 2023, 13(10), 919; https://doi.org/10.3390/bios13100919 - 8 Oct 2023

Cited by 5 | Viewed by 1932

Abstract

Plasticizers are a type of toxic substance that may remain in food, posing significant health risks including carcinogenic, teratogenic, mutagenic, and other adverse effects. In this study, a novel strategy was employed by combining Pt@Au nanozymes with high catalytic properties to created two [...] Read more.

Plasticizers are a type of toxic substance that may remain in food, posing significant health risks including carcinogenic, teratogenic, mutagenic, and other adverse effects. In this study, a novel strategy was employed by combining Pt@Au nanozymes with high catalytic properties to created two catalytic signal probes, designated as Pt@Au@Ab1 and Pt@Au@Ab2, specifically designed for the detection of dimethyl phthalate (DMP) and dibutyl phthalate (DBP). These catalytic signal probes served as the foundation for the development of a colorimetric immunoassay, enabling the simultaneous detection of both DMP and DBP. The colorimetric immunoassay is capable of detecting DMP in the range of 0.5–100 μg/L with a limit of detection as low as 0.1 μg/L and DBP in the range of 1–32 μg/L with a low limit of detection of 0.5 μg/L. The developed immunoassay can be used for the determination of the DMP and DBP in baijiu and plastic bottled drinks. The recovery rate is in the range of 96.4% and 100.5% and the coefficient of variation is between 1.0% and 7.2%. This innovative colorimetric immunoassay offers a robust tool for the simultaneous quantification of DMP and DBP in real samples. Full article

(This article belongs to the Special Issue Application of Nanomaterials for Biosensors)

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