Biosensors

Research

13 pages, 3215 KiB

Open AccessArticle

A Metal-Organic Framework-Based Colorimetric Sensor Array for Transcutaneous CO₂ Monitoring via Lensless Imaging

by Syed Saad Ahmed, Jingjing Yu, Wei Ding, Sabyasachi Ghosh, David Brumels, Songxin Tan, Laxmi Raj Jaishi, Amirhossein Amjad and Xiaojun Xian

Biosensors 2024, 14(11), 516; https://doi.org/10.3390/bios14110516 - 22 Oct 2024

Viewed by 1609

Abstract

Transcutaneous carbon dioxide (TcPCO2) monitoring provides a non-invasive alternative to measuring arterial carbon dioxide (PaCO2), making it valuable for various applications, such as sleep diagnostics and neonatal care. However, traditional transcutaneous monitors are bulky, expensive, and pose risks such as skin burns. To [...] Read more.

Transcutaneous carbon dioxide (TcPCO2) monitoring provides a non-invasive alternative to measuring arterial carbon dioxide (PaCO2), making it valuable for various applications, such as sleep diagnostics and neonatal care. However, traditional transcutaneous monitors are bulky, expensive, and pose risks such as skin burns. To address these limitations, we have introduced a compact, cost-effective CMOS imager-based sensor for TcPCO2 detection by utilizing colorimetric reactions with metal–organic framework (MOF)-based nano-hybrid materials. The sensor, with a colorimetric sensing array fabricated on an ultrathin PDMS membrane and then adhered to the CMOS imager surface, can record real-time sensing data through image processing without the need for additional optical components, which significantly reduces the sensor’s size. Our system shows impressive sensitivity and selectivity, with a low detection limit of 26 ppm, a broad detection range of 0–2% CO₂, and strong resistance to interference from common skin gases. Feasibility tests on human subjects demonstrate the potential of this MOF-CMOS imager-based colorimetric sensor for clinical applications. Additionally, its compact design and responsiveness make it suitable for sports and exercise settings, offering valuable insights into respiratory function and performance. The sensing system’s compact size, low cost, and reversible and highly sensitive TcPCO2 monitoring capability make it ideal for integration into wearable devices for remote health tracking. Full article

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

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11 pages, 8063 KiB

Open AccessArticle

Fundamental Study of a Wristwatch Sweat Lactic Acid Monitor

by Sakae Konno and Hiroyuki Kudo

Biosensors 2024, 14(4), 187; https://doi.org/10.3390/bios14040187 - 10 Apr 2024

Cited by 2 | Viewed by 1886

Abstract

A lactic acid (LA) monitoring system aimed at sweat monitoring was fabricated and tested. The sweat LA monitoring system uses a continuous flow of phosphate buffer saline, instead of chambers or cells, for collecting and storing sweat fluid excreted at the skin surface. [...] Read more.

A lactic acid (LA) monitoring system aimed at sweat monitoring was fabricated and tested. The sweat LA monitoring system uses a continuous flow of phosphate buffer saline, instead of chambers or cells, for collecting and storing sweat fluid excreted at the skin surface. To facilitate the use of the sweat LA monitoring system by subjects when exercising, the fluid control system, including the sweat sampling device, was designed to be unaffected by body movements or muscle deformation. An advantage of our system is that the skin surface condition is constantly refreshed by continuous flow. A real sample test was carried out during stationary bike exercise, which showed that LA secretion increased by approximately 10 μg/cm²/min compared to the baseline levels before exercise. The LA levels recovered to baseline levels after exercise due to the effect of continuous flow. This indicates that the wristwatch sweat LA monitor has the potential to enable a detailed understanding of the LA distribution at the skin surface. Full article

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

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17 pages, 2633 KiB

Open AccessArticle

Monitoring Changes in Oxygen Muscle during Exercise with High-Flow Nasal Cannula Using Wearable NIRS Biosensors

by Felipe Contreras-Briceño, Maximiliano Espinosa-Ramírez, Augusta Rivera-Greene, Camila Guerra-Venegas, Antonia Lungenstrass-Poulsen, Victoria Villagra-Reyes, Raúl Caulier-Cisterna, Oscar F. Araneda and Ginés Viscor

Biosensors 2023, 13(11), 985; https://doi.org/10.3390/bios13110985 - 13 Nov 2023

Cited by 1 | Viewed by 2822

Abstract

Exercise increases the cost of breathing (COB) due to increased lung ventilation (

\dot{V}

E), inducing respiratory muscles deoxygenation (

\nabla

SmO₂), while the increase in workload implies

\nabla

SmO₂ in locomotor muscles. This phenomenon has been proposed as [...] Read more.

Exercise increases the cost of breathing (COB) due to increased lung ventilation (

\dot{V}

E), inducing respiratory muscles deoxygenation (

\nabla

SmO₂), while the increase in workload implies

\nabla

SmO₂ in locomotor muscles. This phenomenon has been proposed as a leading cause of exercise intolerance, especially in clinical contexts. The use of high-flow nasal cannula (HFNC) during exercise routines in rehabilitation programs has gained significant interest because it is proposed as a therapeutic intervention for reducing symptoms associated with exercise intolerance, such as fatigue and dyspnea, assuming that HFNC could reduce exercise-induced

\nabla

SmO₂. SmO₂ can be detected using optical wearable devices provided by near-infrared spectroscopy (NIRS) technology, which measures the changes in the amount of oxygen bound to chromophores (e.g., hemoglobin, myoglobin, cytochrome oxidase) at the target tissue level. We tested in a study with a cross-over design whether the muscular desaturation of m.vastus lateralis and m.intercostales during a high-intensity constant-load exercise can be reduced when it was supported with HFNC in non-physically active adults. Eighteen participants (nine women; age: 22 ± 2 years, weight: 65.1 ± 11.2 kg, height: 173.0 ± 5.8 cm, BMI: 21.6 ± 2.8 kg·m⁻²) were evaluated in a cycle ergometer (15 min, 70% maximum watts achieved in ergospirometry (

\dot{V}

O₂-peak)) breathing spontaneously (control, CTRL) or with HFNC support (HFNC; 50 L·min⁻¹, fiO₂: 21%, 30 °C), separated by seven days in randomized order. Two-way ANOVA tests analyzed the

\nabla

SmO₂ (m.intercostales and m.vastus lateralis), and changes in

\dot{V}

E and

\nabla

SmO₂·

\dot{V}

E⁻¹. Dyspnea, leg fatigue, and effort level (RPE) were compared between trials by the Wilcoxon matched-paired signed rank test. We found that the interaction of factors (trial × exercise-time) was significant in

\nabla

SmO₂-m.intercostales,

\dot{V}

E, and (

\nabla

SmO₂-m.intercostales)/

\dot{V}

E (p < 0.05, all) but not in

\nabla

SmO₂-m.vastus lateralis.

\nabla

SmO₂-m.intercostales was more pronounced in CTRL during exercise since 5′ (p < 0.05). Hyperventilation was higher in CTRL since 10′ (p < 0.05). The

\nabla

SmO₂·

\dot{V}

E⁻¹ decreased during exercise, being lowest in CTRL since 5′. Lower dyspnea was reported in HFNC, with no differences in leg fatigue and RPE. We concluded that wearable optical biosensors documented the beneficial effect of HFNC in COB due to lower respiratory

\nabla

SmO₂ induced by exercise. We suggest incorporating NIRS devices in rehabilitation programs to monitor physiological changes that can support the clinical impact of the therapeutic intervention implemented. Full article

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

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Review

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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 1641

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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17 pages, 3361 KiB

Open AccessReview

Advances in Cardiovascular Wearable Devices

by Sheikh Muhammad Asher Iqbal, Mary Ann Leavitt, Imadeldin Mahgoub and Waseem Asghar

Biosensors 2024, 14(11), 525; https://doi.org/10.3390/bios14110525 - 30 Oct 2024

Viewed by 2587

Abstract

Cardiovascular diseases are a leading cause of death worldwide. They mainly include coronary artery disease, rheumatic heart disease, andcerebrovascular disease, and. Cardiovascular diseases can be better managed and diagnosed using wearable devices. Wearable devices, in comparison to traditional cardiovascular diagnostic tools, are not [...] Read more.

Cardiovascular diseases are a leading cause of death worldwide. They mainly include coronary artery disease, rheumatic heart disease, andcerebrovascular disease, and. Cardiovascular diseases can be better managed and diagnosed using wearable devices. Wearable devices, in comparison to traditional cardiovascular diagnostic tools, are not only inexpensive but also have the potential to provide continuous real-time monitoring. This paper reviews some of the recent advances in cardiovascular wearable devices. It discusses traditional implantable devices for cardiovascular diseases as well as wearable devices. The different types of wearable devices are categorized based on different technologies, namely using galvanic contact, photoplethysmography (PPG), and radio frequency (RF) waves. It also highlights the use of artificial intelligence (AI) in cardiovascular disease diagnostics as well as future perspectives on cardiovascular devices. Full article

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

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25 pages, 14822 KiB

Open AccessReview

Tear-Based Ocular Wearable Biosensors for Human Health Monitoring

by Arunima Rajan, Jithin Vishnu and Balakrishnan Shankar

Biosensors 2024, 14(10), 483; https://doi.org/10.3390/bios14100483 - 8 Oct 2024

Viewed by 5574

Abstract

Wearable tear-based biosensors have garnered substantial interest for real time monitoring with an emphasis on personalized health care. These biosensors utilize major tear biomarkers such as proteins, lipids, metabolites, and electrolytes for the detection and recording of stable biological signals in a non-invasive [...] Read more.

Wearable tear-based biosensors have garnered substantial interest for real time monitoring with an emphasis on personalized health care. These biosensors utilize major tear biomarkers such as proteins, lipids, metabolites, and electrolytes for the detection and recording of stable biological signals in a non-invasive manner. The present comprehensive review delves deep into the tear composition along with potential biomarkers that can identify, monitor, and predict certain ocular diseases such as dry eye disease, conjunctivitis, eye-related infections, as well as diabetes mellitus. Recent technologies in tear-based wearable point-of-care medical devices, specifically the state-of-the-art and prospects of glucose, pH, lactate, protein, lipid, and electrolyte sensing from tear are discussed. Finally, the review addresses the existing challenges associated with the widespread application of tear-based sensors, which will pave the way for advanced scientific research and development of such non-invasive health monitoring devices. Full article

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

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22 pages, 1736 KiB

Open AccessReview

New Advances in Antenna Design toward Wearable Devices Based on Nanomaterials

by Chunge Wang, Ning Zhang, Chen Liu, Bangbang Ma, Keke Zhang, Rongzhi Li, Qianqian Wang and Sheng Zhang

Biosensors 2024, 14(1), 35; https://doi.org/10.3390/bios14010035 - 10 Jan 2024

Cited by 7 | Viewed by 5437

Abstract

Wearable antennas have recently garnered significant attention due to their attractive properties and potential for creating lightweight, compact, low-cost, and multifunctional wireless communication systems. With the breakthrough progress in nanomaterial research, the use of lightweight materials has paved the way for the widespread [...] Read more.

Wearable antennas have recently garnered significant attention due to their attractive properties and potential for creating lightweight, compact, low-cost, and multifunctional wireless communication systems. With the breakthrough progress in nanomaterial research, the use of lightweight materials has paved the way for the widespread application of wearable antennas. Compared with traditional metallic materials like copper, aluminum, and nickel, nanoscale entities including zero-dimensional (0-D) nanoparticles, one-dimensional (1-D) nanofibers or nanotubes, and two-dimensional (2-D) nanosheets exhibit superior physical, electrochemical, and performance characteristics. These properties significantly enhance the potential for constructing durable electronic composites. Furthermore, the antenna exhibits compact size and high deformation stability, accompanied by greater portability and wear resistance, owing to the high surface-to-volume ratio and flexibility of nanomaterials. This paper systematically discusses the latest advancements in wearable antennas based on 0-D, 1-D, and 2-D nanomaterials, providing a comprehensive overview of their development and future prospects in the field. Full article

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

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Other

Jump to: Research, Review

18 pages, 2000 KiB

Open AccessSystematic Review

Is Breath Best? A Systematic Review on the Accuracy and Utility of Nanotechnology Based Breath Analysis of Ketones in Type 1 Diabetes

by Kamal Marfatia, Jing Ni, Veronica Preda and Noushin Nasiri

Biosensors 2025, 15(1), 62; https://doi.org/10.3390/bios15010062 - 19 Jan 2025

Viewed by 709

Abstract

Timely ketone detection in patients with type 1 diabetes mellitus (T1DM) is critical for the effective management of diabetic ketoacidosis (DKA). This systematic review evaluates the current literature on breath-based analysis for ketone detection in T1DM, highlighting nanotechnology as a potential for a [...] Read more.

Timely ketone detection in patients with type 1 diabetes mellitus (T1DM) is critical for the effective management of diabetic ketoacidosis (DKA). This systematic review evaluates the current literature on breath-based analysis for ketone detection in T1DM, highlighting nanotechnology as a potential for a non-invasive alternative to blood-based ketone measurements. A comprehensive search across 5 databases identified 11 studies meeting inclusion criteria, showcasing various breath analysis techniques, such as semiconducting gas sensors, colorimetry, and nanoparticle-based chemo-resistive sensors. These studies report high sensitivity and correlation between breath acetone (BrAce) levels and blood ketones, with some demonstrating accuracies up to 94.7% and correlations reaching R² values as high as 0.98. However, significant heterogeneity in methodologies and cut-off values limits device comparability and precludes meta-analysis. Despite these challenges, the findings indicate that BrAce monitoring could offer significant clinical benefits by enabling the earlier detection of ketone buildup, reducing DKA-related hospitalisations and healthcare costs. Standardising BrAce measurement techniques and sensitivity thresholds is essential to broaden clinical adoption. This review underscores the promise of nanotechnology-based breath analysis as a transformative tool for DKA management, with potential utility across varied ketotic conditions. Full article

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

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