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Biosensors
Volume 13
Issue 9
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Biosensors, Volume 13, Issue 9 (September 2023) – 65 articles

Cover Story (view full-size image): In this study, a modular, multi-purpose, and cost-effective electrochemical biosensor based on a five-stranded four-way junction (5S-4WJ) system was developed for SARS-CoV-2 (genes S and N) and influenza A virus (gene M) detection. The 5S-4WJ structure consists of an electrode-immobilized universal stem-loop (USL) strand, two auxiliary DNA strands, and a universal methylene blue redox strand (UMeB). The sequence-specific auxiliary DNA strands (m and f) ensure selectivity of the biosensor for target recognition utilizing the same USL and UMeB components. The biosensor exhibited minimal loss in the signal after rehybridization, demonstrating its potential as a viable multiplex assay for both current and future pathogens, with a low limit of quantification (LOQ) of as low as 17 pM. View this paper
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24 pages, 4288 KiB  
Review
Recent Progresses in Optical Biosensors for Interleukin 6 Detection
by Marjan Majdinasab, Marc Lamy de la Chapelle and Jean Louis Marty
Biosensors 2023, 13(9), 898; https://doi.org/10.3390/bios13090898 - 21 Sep 2023
Cited by 1 | Viewed by 1687
Abstract
Interleukin 6 (IL-6) is pleiotropic cytokine with pathological pro-inflammatory effects in various acute, chronic and infectious diseases. It is involved in a variety of biological processes including immune regulation, hematopoiesis, tissue repair, inflammation, oncogenesis, metabolic control, and sleep. Due to its important role [...] Read more.
Interleukin 6 (IL-6) is pleiotropic cytokine with pathological pro-inflammatory effects in various acute, chronic and infectious diseases. It is involved in a variety of biological processes including immune regulation, hematopoiesis, tissue repair, inflammation, oncogenesis, metabolic control, and sleep. Due to its important role as a biomarker of many types of diseases, its detection in small amounts and with high selectivity is of particular importance in medical and biological fields. Laboratory methods including enzyme-linked immunoassays (ELISAs) and chemiluminescent immunoassays (CLIAs) are the most common conventional methods for IL-6 detection. However, these techniques suffer from the complexity of the method, the expensiveness, and the time-consuming process of obtaining the results. In recent years, too many attempts have been conducted to provide simple, rapid, economical, and user-friendly analytical approaches to monitor IL-6. In this regard, biosensors are considered desirable tools for IL-6 detection because of their special features such as high sensitivity, rapid detection time, ease of use, and ease of miniaturization. In this review, current progresses in different types of optical biosensors as the most favorable types of biosensors for the detection of IL-6 are discussed, evaluated, and compared. Full article
(This article belongs to the Special Issue Trend in Optical Sensors for Medical Diagnostics and Therapeutics)
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27 pages, 7670 KiB  
Article
Novel Cytochrome P450-3A4 Enzymatic Nanobiosensor for Lapatinib (a Breast Cancer Drug) Developed on a Poly(anilino-co-4-aminobenzoic Acid-Green-Synthesised Indium Nanoparticle) Platform
by Jaymi Leigh January, Ziyanda Zamaswazi Tshobeni, Nokwanda Precious Pearl Ngema, Abongile Nwabisa Jijana, Emmanuel Iheanyichukwu Iwuoha, Takalani Mulaudzi, Samantha Fiona Douman and Rachel Fanelwa Ajayi
Biosensors 2023, 13(9), 897; https://doi.org/10.3390/bios13090897 - 21 Sep 2023
Viewed by 1363
Abstract
Breast cancer (BC) is one of the most common types of cancer disease worldwide and it accounts for thousands of deaths annually. Lapatinib is among the preferred drugs for the treatment of breast cancer. Possible drug toxicity effects of lapatinib can be controlled [...] Read more.
Breast cancer (BC) is one of the most common types of cancer disease worldwide and it accounts for thousands of deaths annually. Lapatinib is among the preferred drugs for the treatment of breast cancer. Possible drug toxicity effects of lapatinib can be controlled by real-time determination of the appropriate dose for a patient at the point of care. In this study, a novel highly sensitive polymeric nanobiosensor for lapatinib is presented. A composite of poly(anilino-co-4-aminobenzoic acid) co-polymer {poly(ANI-co-4-ABA)} and coffee extract-based green-synthesized indium nanoparticles (InNPs) was used to develop the sensor platform on a screen-printed carbon electrode (SPCE), i.e., SPCE||poly(ANI-co-4-ABA-InNPs). Cytochrome P450-3A4 (CYP3A4) enzyme and polyethylene glycol (PEG) were incorporated on the modified platform to produce the SPCE||poly(ANI-co-4-ABA-InNPs)|CYP3A4|PEG lapatinib nanobiosensor. Experiments for the determination of the electrochemical response characteristics of the nanobiosensor were performed with cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The nanobiosensor calibration for 0–100 ng/mL lapatinib was linear and gave limit of detection (LOD) values of 13.21 ng/mL lapatinib and 18.6 ng/mL lapatinib in physiological buffer and human serum, respectively. The LOD values are much lower than the peak plasma concentration (Cmax) of lapatinib (2.43 µg/mL), which is attained 4 h after the administration of a daily dose of 1250 mg lapatinib. The electrochemical nanobiosensor also exhibited excellent anti-interference performance and stability. Full article
(This article belongs to the Special Issue Advanced Materials for Electrochemical Sensors and Biosensors Development)
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35 pages, 9817 KiB  
Review
A Review of Manufacturing Methods for Flexible Devices and Energy Storage Devices
by Yuntao Han, Yunwei Cui, Xuxian Liu and Yaqun Wang
Biosensors 2023, 13(9), 896; https://doi.org/10.3390/bios13090896 - 20 Sep 2023
Cited by 2 | Viewed by 2084
Abstract
Given the advancements in modern living standards and technological development, conventional smart devices have proven inadequate in meeting the demands for a high-quality lifestyle. Therefore, a revolution is necessary to overcome this impasse and facilitate the emergence of flexible electronics. Specifically, there is [...] Read more.
Given the advancements in modern living standards and technological development, conventional smart devices have proven inadequate in meeting the demands for a high-quality lifestyle. Therefore, a revolution is necessary to overcome this impasse and facilitate the emergence of flexible electronics. Specifically, there is a growing focus on health detection, necessitating advanced flexible preparation technology for biosensor-based smart wearable devices. Nowadays, numerous flexible products are available on the market, such as electronic devices with flexible connections, bendable LED light arrays, and flexible radio frequency electronic tags for storing information. The manufacturing process of these devices is relatively straightforward, and their integration is uncomplicated. However, their functionality remains limited. Further research is necessary for the development of more intricate applications, such as intelligent wearables and energy storage systems. Taking smart wear as an example, it is worth noting that the current mainstream products on the market primarily consist of bracelet-type health testing equipment. They exhibit limited flexibility and can only be worn on the wrist for measurement purposes, which greatly limits their application diversity. Flexible energy storage and flexible display also face the same problem, so there is still a lot of room for development in the field of flexible electronics manufacturing. In this review, we provide a brief overview of the developmental history of flexible devices, systematically summarizing representative preparation methods and typical applications, identifying challenges, proposing solutions, and offering prospects for future development. Full article
(This article belongs to the Special Issue Wearable Bioelectronic Devices Based on Stretchable Textile)
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14 pages, 2971 KiB  
Article
Comparative Study of SERS-Spectra of NQ21 Peptide on Silver Particles and in Gold-Coated “Nanovoids”
by Siarhei Zavatski, Sergey Dubkov, Dmitry Gromov and Hanna Bandarenka
Biosensors 2023, 13(9), 895; https://doi.org/10.3390/bios13090895 - 20 Sep 2023
Viewed by 1005
Abstract
The NQ21 peptide has relatively recently attracted attention in the biomedical sphere due to its prospects for facilitating the engineering of the HIV1 vaccine and ELISA test. Today, there is still a need for a reliable and fast methodology that reveals the secondary [...] Read more.
The NQ21 peptide has relatively recently attracted attention in the biomedical sphere due to its prospects for facilitating the engineering of the HIV1 vaccine and ELISA test. Today, there is still a need for a reliable and fast methodology that reveals the secondary structure of this analyte at the low concentrations conventionally used in vaccines and immunological assays. The present research determined the differences between the surface-enhanced Raman scattering (SERS) spectra of NQ21 peptide molecules adsorbed on solid SERS-active substrates depending on their geometry and composition. The ultimate goal of our research was to propose an algorithm and SERS-active material for structural analysis of peptides. Phosphate buffer solutions of the 30 µg/mL NQ21 peptide at different pH levels were used for the SERS measurements, with silver particles on mesoporous silicon and gold-coated “nanovoids” in macroporous silicon. The SERS analysis of the NQ21 peptide was carried out by collecting the SERS spectra maps. The map assessment with an originally developed algorithm resulted in defining the effect of the substrate on the secondary structure of the analyte molecules. Silver particles are recommended for peptide detection if it is not urgent to precisely reveal all the characteristic bands, because they provide greater enhancement but are accompanied by analyte destruction. If the goal is to carefully study the secondary structure and composition of the peptide, it is better to use SERS-active gold-coated “nanovoids”. Objective results can be obtained by collecting at least three 15 × 15 maps of the SERS spectra of a given peptide on substrates from different batches. Full article
(This article belongs to the Special Issue Nanostructures for Tip and Surface Enhanced Vibrational Spectroscopy (TERS, SERS, SEIRA, SECARS))
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18 pages, 5184 KiB  
Article
Development of a Multiplex HIV/TB Diagnostic Assay Based on the Microarray Technology
by Kanyane Malatji, Advaita Singh, Christina Thobakgale and Kabamba Alexandre
Biosensors 2023, 13(9), 894; https://doi.org/10.3390/bios13090894 - 20 Sep 2023
Cited by 1 | Viewed by 1089
Abstract
Currently there are diagnostic tests available for human immunodeficiency virus (HIV) and tuberculosis (TB); however, they are still diagnosed separately, which can delay treatment in cases of co-infection. Here we report on a multiplex microarray technology for the detection of HIV and TB [...] Read more.
Currently there are diagnostic tests available for human immunodeficiency virus (HIV) and tuberculosis (TB); however, they are still diagnosed separately, which can delay treatment in cases of co-infection. Here we report on a multiplex microarray technology for the detection of HIV and TB antibodies using p24 as well as TB CFP10, ESAT6 and pstS1 antigens on epoxy-silane slides. To test this technology for antigen–antibody interactions, immobilized antigens were exposed to human sera spiked with physiological concentrations of primary antibodies, followed by secondary antibodies conjugated to a fluorescent reporter. HIV and TB antibodies were captured with no cross-reactivity observed. The sensitivity of the slides was compared to that of high-binding plates. We found that the slides were more sensitive, with the detection limit being 0.000954 µg/mL compared to 4.637 µg/mL for the plates. Furthermore, stability studies revealed that the immobilized antigens could be stored dry for at least 90 days and remained stable across all pH and temperatures assessed, with pH 7.4 and 25 °C being optimal. The data collectively suggested that the HIV/TB multiplex detection technology we developed has the potential for use to diagnose HIV and TB co-infection, and thus can be developed further for the purpose. Full article
(This article belongs to the Section Biosensors and Healthcare)
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15 pages, 3698 KiB  
Article
Tablet-Based Sensor: A Stable and User-Friendly Tool for Point-of-Care Detection of Glucose in Urine
by Hasti Hajimiri, Seyed Hamid Safiabadi Tali, Muna Al-Kassawneh, Zubi Sadiq and Sana Jahanshahi-Anbuhi
Biosensors 2023, 13(9), 893; https://doi.org/10.3390/bios13090893 - 19 Sep 2023
Viewed by 1131
Abstract
The colorimetric detection of glucose in urine through enzymatic reactions offers a low-cost and non-invasive method to aid in diabetes management. Nonetheless, the vulnerability of enzymes to environmental conditions, particularly elevated temperatures, and their activity loss pose significant challenges for transportation and storage. [...] Read more.
The colorimetric detection of glucose in urine through enzymatic reactions offers a low-cost and non-invasive method to aid in diabetes management. Nonetheless, the vulnerability of enzymes to environmental conditions, particularly elevated temperatures, and their activity loss pose significant challenges for transportation and storage. In this work, we developed a stable and portable tablet sensor as a user-friendly platform for glucose monitoring. This innovative device encapsulates glucose oxidase and horseradish peroxidase enzymes with dextran, transforming them into solid tablets and ensuring enhanced stability and practicality. The enzymatic tablet-based sensor detected glucose in urine samples within 5 min, using 3,3′,5,5′-tetramethylbenzidine (TMB) as the indicator. The tablet sensor exhibited responsive performance within the clinically relevant range of 0–6 mM glucose, with a limit of detection of 0.013 mM. Furthermore, the tablets detected glucose in spiked real human urine samples, without pre-processing, with high precision. Additionally, with regard to thermal stability, the enzyme tablets better maintained their activity at an elevated temperature as high as 60 °C compared to the solution-phase enzymes, demonstrating the enhanced stability of the enzymes under harsh conditions. The availability of these stable and portable tablet sensors will greatly ease the transportation and application of glucose sensors, enhancing the accessibility of glucose monitoring, particularly in resource-limited settings. Full article
(This article belongs to the Section Biosensors and Healthcare)
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27 pages, 5084 KiB  
Review
An Updated Review on Electrochemical Nanobiosensors for Neurotransmitter Detection
by Hye Kyu Choi, Jin-Ha Choi and Jinho Yoon
Biosensors 2023, 13(9), 892; https://doi.org/10.3390/bios13090892 - 19 Sep 2023
Cited by 3 | Viewed by 2145
Abstract
Neurotransmitters are chemical compounds released by nerve cells, including neurons, astrocytes, and oligodendrocytes, that play an essential role in the transmission of signals in living organisms, particularly in the central nervous system, and they also perform roles in realizing the function and maintaining [...] Read more.
Neurotransmitters are chemical compounds released by nerve cells, including neurons, astrocytes, and oligodendrocytes, that play an essential role in the transmission of signals in living organisms, particularly in the central nervous system, and they also perform roles in realizing the function and maintaining the state of each organ in the body. The dysregulation of neurotransmitters can cause neurological disorders. This highlights the significance of precise neurotransmitter monitoring to allow early diagnosis and treatment. This review provides a complete multidisciplinary examination of electrochemical biosensors integrating nanomaterials and nanotechnologies in order to achieve the accurate detection and monitoring of neurotransmitters. We introduce extensively researched neurotransmitters and their respective functions in biological beings. Subsequently, electrochemical biosensors are classified based on methodologies employed for direct detection, encompassing the recently documented cell-based electrochemical monitoring systems. These methods involve the detection of neurotransmitters in neuronal cells in vitro, the identification of neurotransmitters emitted by stem cells, and the in vivo monitoring of neurotransmitters. The incorporation of nanomaterials and nanotechnologies into electrochemical biosensors has the potential to assist in the timely detection and management of neurological disorders. This study provides significant insights for researchers and clinicians regarding precise neurotransmitter monitoring and its implications regarding numerous biological applications. Full article
(This article belongs to the Special Issue Hybrid Bioelectronic Nanocomposites for Biosensing Applications)
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32 pages, 16428 KiB  
Review
Insights into the Fabrication and Electrochemical Aspects of Paper Microfluidics-Based Biosensor Module
by Rohini Kumari, Akanksha Singh, Uday Pratap Azad and Pranjal Chandra
Biosensors 2023, 13(9), 891; https://doi.org/10.3390/bios13090891 - 19 Sep 2023
Viewed by 1924
Abstract
Over the past ten years, microfluidic paper-based analytical devices (micro-PADs) have attracted a lot of attention as a viable analytical platform. It is expanding as a result of advances in manufacturing processes and device integration. Conventional microfluidics approaches have some drawbacks, including high [...] Read more.
Over the past ten years, microfluidic paper-based analytical devices (micro-PADs) have attracted a lot of attention as a viable analytical platform. It is expanding as a result of advances in manufacturing processes and device integration. Conventional microfluidics approaches have some drawbacks, including high costs, lengthy evaluation times, complicated fabrication, and the necessity of experienced employees. Hence, it is extremely important to construct a detection system that is quick, affordable, portable, and efficient. Nowadays, micro-PADs are frequently employed, particularly in electrochemical analyses, to replicate the classic standard laboratory experiments on a miniature paper chip. It has benefits like rapid assessment, small sample consumption, quick reaction, accuracy, and multiplex function. The goal of this review is to examine modern paper microfluidics-based electrochemical sensing devices for the detection of macromolecules, small molecules, and cells in a variety of real samples. The design and fabrication of micro-PADs using conventional and the latest techniques have also been discussed in detail. Lastly, the limitations and potential of these analytical platforms are examined in order to shed light on future research. Full article
(This article belongs to the Special Issue Cellulose-Based Biosensing Platforms, Volume II)
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17 pages, 2715 KiB  
Article
Genetically Encoded Fluorescent Probe for Detection of Heme-Induced Conformational Changes in Cytochrome c
by Mehmet Yunus Genceroglu, Cansu Cavdar, Selen Manioglu and Halil Bayraktar
Biosensors 2023, 13(9), 890; https://doi.org/10.3390/bios13090890 - 18 Sep 2023
Viewed by 1360
Abstract
Cytochrome c (Cytc) is a key redox protein for energy metabolism and apoptosis in cells. The activation of Cytc is composed of several steps, including its transfer to the mitochondrial membrane, binding to cytochrome c heme lyase (CCHL) and covalent attachment to heme. [...] Read more.
Cytochrome c (Cytc) is a key redox protein for energy metabolism and apoptosis in cells. The activation of Cytc is composed of several steps, including its transfer to the mitochondrial membrane, binding to cytochrome c heme lyase (CCHL) and covalent attachment to heme. The spectroscopic methods are often applied to study the structural changes of Cytc. However, they require the isolation of Cytc from cells and have limited availability under physiological conditions. Despite recent studies to elucidate the tightly regulated folding mechanism of Cytc, the role of these events and their association with different conformational states remain elusive. Here, we provide a genetically encoded fluorescence method that allows monitoring of the conformational changes of Cytc upon binding to heme and CCHL. Cerulean and Venus fluorescent proteins attached at the N and C terminals of Cytc can be used to determine its unfolded, intermediate, and native states by measuring FRET amplitude. We found that the noncovalent interaction of heme in the absence of CCHL induced a shift in the FRET signal, indicating the formation of a partially folded state. The higher concentration of heme and coexpression of CCHL gave rise to the recovery of Cytc native structure. We also found that Cytc was weakly associated with CCHL in the absence of heme. As a result, a FRET-based fluorescence approach was demonstrated to elucidate the mechanism of heme-induced Cytc conformational changes with spatiotemporal resolution and can be applied to study its interaction with small molecules and other protein partners in living cells. Full article
(This article belongs to the Section Optical and Photonic Biosensors)
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28 pages, 9556 KiB  
Review
Unraveling the Possibilities: Recent Progress in DNA Biosensing
by Meng Yu, Tingli He, Qianqian Wang and Cheng Cui
Biosensors 2023, 13(9), 889; https://doi.org/10.3390/bios13090889 - 18 Sep 2023
Cited by 2 | Viewed by 1609
Abstract
Due to the advantages of its numerous modification sites, predictable structure, high thermal stability, and excellent biocompatibility, DNA is the ideal choice as a key component of biosensors. DNA biosensors offer significant advantages over existing bioanalytical techniques, addressing limitations in sensitivity, selectivity, and [...] Read more.
Due to the advantages of its numerous modification sites, predictable structure, high thermal stability, and excellent biocompatibility, DNA is the ideal choice as a key component of biosensors. DNA biosensors offer significant advantages over existing bioanalytical techniques, addressing limitations in sensitivity, selectivity, and limit of detection. Consequently, they have attracted significant attention from researchers worldwide. Here, we exemplify four foundational categories of functional nucleic acids: aptamers, DNAzymes, i-motifs, and G-quadruplexes, from the perspective of the structure-driven functionality in constructing DNA biosensors. Furthermore, we provide a concise overview of the design and detection mechanisms employed in these DNA biosensors. Noteworthy advantages of DNA as a sensor component, including its programmable structure, reaction predictility, exceptional specificity, excellent sensitivity, and thermal stability, are highlighted. These characteristics contribute to the efficacy and reliability of DNA biosensors. Despite their great potential, challenges remain for the successful application of DNA biosensors, spanning storage and detection conditions, as well as associated costs. To overcome these limitations, we propose potential strategies that can be implemented to solve these issues. By offering these insights, we aim to inspire subsequent researchers in related fields. Full article
(This article belongs to the Section Biosensors and Healthcare)
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12 pages, 4749 KiB  
Article
Establishment and Validation of an Integrated Microfluidic Step Emulsification Chip Supporting Droplet Digital Nucleic Acid Analysis
by Gangyin Luo, Ying Zhang, Shun Wang, Xinbei Lv, Tianhang Yang and Jinxian Wang
Biosensors 2023, 13(9), 888; https://doi.org/10.3390/bios13090888 - 18 Sep 2023
Viewed by 1065
Abstract
Uniform and stable droplet generation is critical for accurate and efficient digital nucleic acid analysis (dNAA). In this study, an integrated microfluidic step emulsification device with wide-range droplet generation capability, small device dimensions, convenient fabrication strategy, low contamination and high robustness was developed. [...] Read more.
Uniform and stable droplet generation is critical for accurate and efficient digital nucleic acid analysis (dNAA). In this study, an integrated microfluidic step emulsification device with wide-range droplet generation capability, small device dimensions, convenient fabrication strategy, low contamination and high robustness was developed. A tree-shaped droplet generation nozzle distribution design was proposed to increase the uniformity of droplet generation by equating flow rates, and the flow field in the design was numerically simulated. Theoretical analysis and comparative experiments on droplet size were performed regarding the influences of nozzle dimensions and surface properties. With incubation and hydrophobic reagent treatment, droplets as small as 73.1 μm were generated with multiplex nozzles of 18 μm (h) × 80 μm (w). The droplets were then collected into a standard PCR tube and an on-chip monolayer droplet collection chamber, without manual transfer and sample contamination. The oil-to-sample volume ratio in the PCR tube was recorded during collection. In the end, the droplets generated and collected using the microfluidic device proved to be stable and uniform for nucleic acid amplification and detection. This study provides reliable characteristic information for the design and fabrication of a micro-droplet generation device, and represents a promising approach for the realization of a three-in-one dNAA device under a step emulsification method. Full article
(This article belongs to the Special Issue Microfluidics for Biomedical Applications (Volume II))
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11 pages, 2604 KiB  
Article
Rapid Evaluation of Antibacterial Carbohydrates on a Microfluidic Chip Integrated with the Impedimetric Neoglycoprotein Biosensor
by Haijie Ji, Xueqiong Yang, Hang Zhou, Feiyun Cui and Qin Zhou
Biosensors 2023, 13(9), 887; https://doi.org/10.3390/bios13090887 - 18 Sep 2023
Viewed by 1035
Abstract
The colonization of some bacteria to their host cell is mediated by selective adhesion between adhesin and glycan. The evaluation of antiadhesive carbohydrates in vitro has great significance in discovering new antibacterial drugs. In this paper, a microfluidic chip integrated with impedimetric neoglycoprotein [...] Read more.
The colonization of some bacteria to their host cell is mediated by selective adhesion between adhesin and glycan. The evaluation of antiadhesive carbohydrates in vitro has great significance in discovering new antibacterial drugs. In this paper, a microfluidic chip integrated with impedimetric neoglycoprotein biosensors was developed to evaluate the antibacterial effect of carbohydrates. Mannosylated bovine serum albumin (Man-BSA) was taken as the neoglycoprotein and immobilized on the microelectrode-modified gold nanoparticles (Au NPs) to form a bionic glycoprotein nanosensing surface (Man-BSA/Au NPs). Salmonella typhimurium (S. typhimurium) was selected as a bacteria model owing to its selective adhesion to the mannose. Electrochemical impedance spectroscopy (EIS) was used to characterize the adhesion capacity of S. typhimurium to the Man-BSA/Au NPs and evaluate the antiadhesive efficacy of nine different carbohydrates. It was illustrated that the 4-methoxyphenyl-α-D-pyran mannoside (Phenyl-Man) and mannan peptide (Mannatide) showed excellent antiadhesive efficacy, with IC50 values of 0.086 mM and 0.094 mM, respectively. The microfluidic device developed in this study can be tested in multiple channels. Compared with traditional methods for evaluating the antibacterial drug in vitro, it has the advantages of being fast, convenient, and cost-effective. Full article
(This article belongs to the Special Issue Biosensors for Biomedical Diagnostics)
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37 pages, 4267 KiB  
Review
Immobilization of Enzyme Electrochemical Biosensors and Their Application to Food Bioprocess Monitoring
by Ganchao Sun, Xiaobo Wei, Dianping Zhang, Liben Huang, Huiyan Liu and Haitian Fang
Biosensors 2023, 13(9), 886; https://doi.org/10.3390/bios13090886 - 17 Sep 2023
Cited by 3 | Viewed by 2671
Abstract
Electrochemical biosensors based on immobilized enzymes are among the most popular and commercially successful biosensors. The literature in this field suggests that modification of electrodes with nanomaterials is an excellent method for enzyme immobilization, which can greatly improve the stability and sensitivity of [...] Read more.
Electrochemical biosensors based on immobilized enzymes are among the most popular and commercially successful biosensors. The literature in this field suggests that modification of electrodes with nanomaterials is an excellent method for enzyme immobilization, which can greatly improve the stability and sensitivity of the sensor. However, the poor stability, weak reproducibility, and limited lifetime of the enzyme itself still limit the requirements for the development of enzyme electrochemical biosensors for food production process monitoring. Therefore, constructing sensing technologies based on enzyme electrochemical biosensors remains a great challenge. This article outlines the construction principles of four generations of enzyme electrochemical biosensors and discusses the applications of single-enzyme systems, multi-enzyme systems, and nano-enzyme systems developed based on these principles. The article further describes methods to improve enzyme immobilization by combining different types of nanomaterials such as metals and their oxides, graphene-related materials, metal–organic frameworks, carbon nanotubes, and conducting polymers. In addition, the article highlights the challenges and future trends of enzyme electrochemical biosensors, providing theoretical support and future perspectives for further research and development of high-performance enzyme chemical biosensors. Full article
(This article belongs to the Section Environmental Biosensors and Biosensing)
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28 pages, 4430 KiB  
Review
Recent Uses of Paper Microfluidics in Isothermal Nucleic Acid Amplification Tests
by Jocelyn Reynolds, Reid S. Loeffler, Preston J. Leigh, Hannah A. Lopez and Jeong-Yeol Yoon
Biosensors 2023, 13(9), 885; https://doi.org/10.3390/bios13090885 - 15 Sep 2023
Cited by 1 | Viewed by 1871
Abstract
Isothermal nucleic acid amplification tests have recently gained popularity over polymerase chain reaction (PCR), as they only require a constant temperature and significantly simplify nucleic acid amplification. Recently, numerous attempts have been made to incorporate paper microfluidics into these isothermal amplification tests. Paper [...] Read more.
Isothermal nucleic acid amplification tests have recently gained popularity over polymerase chain reaction (PCR), as they only require a constant temperature and significantly simplify nucleic acid amplification. Recently, numerous attempts have been made to incorporate paper microfluidics into these isothermal amplification tests. Paper microfluidics (including lateral flow strips) have been used to extract nucleic acids, amplify the target gene, and detect amplified products, all toward automating the process. We investigated the literature from 2020 to the present, i.e., since the onset of the COVID-19 pandemic, during which a significant surge in isothermal amplification tests has been observed. Paper microfluidic detection has been used extensively for recombinase polymerase amplification (RPA) and its related methods, along with loop-mediated isothermal amplification (LAMP) and rolling circle amplification (RCA). Detection was conducted primarily with colorimetric and fluorometric methods, although a few publications demonstrated flow distance- and surface-enhanced Raman spectroscopic (SERS)-based detection. A good number of publications could be found that demonstrated both amplification and detection on paper microfluidic platforms. A small number of publications could be found that showed extraction or all three procedures (i.e., fully integrated systems) on paper microfluidic platforms, necessitating the need for future work. Full article
(This article belongs to the Special Issue Paper-Based Microfluidic Devices and Applications)
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28 pages, 49182 KiB  
Review
Advancing Healthcare: Synergizing Biosensors and Machine Learning for Early Cancer Diagnosis
by Mahtab Kokabi, Muhammad Nabeel Tahir, Darshan Singh and Mehdi Javanmard
Biosensors 2023, 13(9), 884; https://doi.org/10.3390/bios13090884 - 13 Sep 2023
Cited by 4 | Viewed by 2352
Abstract
Cancer is a fatal disease and a significant cause of millions of deaths. Traditional methods for cancer detection often have limitations in identifying the disease in its early stages, and they can be expensive and time-consuming. Since cancer typically lacks symptoms and is [...] Read more.
Cancer is a fatal disease and a significant cause of millions of deaths. Traditional methods for cancer detection often have limitations in identifying the disease in its early stages, and they can be expensive and time-consuming. Since cancer typically lacks symptoms and is often only detected at advanced stages, it is crucial to use affordable technologies that can provide quick results at the point of care for early diagnosis. Biosensors that target specific biomarkers associated with different types of cancer offer an alternative diagnostic approach at the point of care. Recent advancements in manufacturing and design technologies have enabled the miniaturization and cost reduction of point-of-care devices, making them practical for diagnosing various cancer diseases. Furthermore, machine learning (ML) algorithms have been employed to analyze sensor data and extract valuable information through the use of statistical techniques. In this review paper, we provide details on how various machine learning algorithms contribute to the ongoing development of advanced data processing techniques for biosensors, which are continually emerging. We also provide information on the various technologies used in point-of-care cancer diagnostic biosensors, along with a comparison of the performance of different ML algorithms and sensing modalities in terms of classification accuracy. Full article
(This article belongs to the Special Issue Nano-Biosensors for Detection and Monitoring)
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11 pages, 2032 KiB  
Article
An Anthracene Carboxamide-Based Fluorescent Probe for Rapid and Sensitive Detection of Mitochondrial Hypochlorite in Living Cells
by Xueling Liu, Yali Wang, Guangshuai Zhou and Wenzhou Zhang
Biosensors 2023, 13(9), 883; https://doi.org/10.3390/bios13090883 - 12 Sep 2023
Viewed by 946
Abstract
Mitochondrial hypochlorite (ClO−) plays important and often contradictory roles in maintaining the redox balance of mitochondria. Abnormal ClO− levels can induce mitochondrial inactivation and further cause cell apoptosis. Herein, we have developed an anthracene carboxyimide-based fluorescent probe mito-ACS for imaging [...] Read more.
Mitochondrial hypochlorite (ClO−) plays important and often contradictory roles in maintaining the redox balance of mitochondria. Abnormal ClO− levels can induce mitochondrial inactivation and further cause cell apoptosis. Herein, we have developed an anthracene carboxyimide-based fluorescent probe mito-ACS for imaging mitochondrial ClO− in living cells. This probe exhibits some distinctive features as excellent resistance to photobleaching, high selectivity and sensitivity, as well as good water solubility. Mito-ACS showed a noticeable fluorescence response toward ClO− with a fast response (within 6 s) and a low detection limit (23 nM). Moreover, the introduction of triphenylphosphonium makes the probe soluble in water and selectively localizes to mitochondria. Furthermore, mito-ACS was successfully applied to image mitochondria ClO− in living cells with low toxicity. Remarkably. the less used fluorophore anthracene carboxyimide exhibiting excellent photostability and desirable optical properties provides a promising application prospect in biological systems. Full article
(This article belongs to the Special Issue Fluorescent Probe for Biosensing and Cell Imaging)
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18 pages, 1644 KiB  
Review
Circulating Tumor Cells Adhesion: Application in Biosensors
by Eduarda B. Paglia, Estela K. K. Baldin, Gabriela P. Freitas, Thalyta S. A. Santiago, João B. M. R. Neto, Jorge V. L. Silva, Hernandes F. Carvalho and Marisa M. Beppu
Biosensors 2023, 13(9), 882; https://doi.org/10.3390/bios13090882 - 12 Sep 2023
Cited by 1 | Viewed by 1324
Abstract
The early and non-invasive diagnosis of tumor diseases has been widely investigated by the scientific community focusing on the development of sensors/biomarkers that act as a way of recognizing the adhesion of circulating tumor cells (CTCs). As a challenge in this area, strategies [...] Read more.
The early and non-invasive diagnosis of tumor diseases has been widely investigated by the scientific community focusing on the development of sensors/biomarkers that act as a way of recognizing the adhesion of circulating tumor cells (CTCs). As a challenge in this area, strategies for CTCs capture and enrichment currently require improvements in the sensors/biomarker’s selectivity. This can be achieved by understanding the biological recognition factors for different cancer cell lines and also by understanding the interaction between surface parameters and the affinity between macromolecules and the cell surface. To overcome some of these concerns, electrochemical sensors have been used as precise, fast-response, and low-cost transduction platforms for application in cytosensors. Additionally, distinct materials, geometries, and technologies have been investigated to improve the sensitivity and specificity properties of the support electrode that will transform biochemical events into electrical signals. This review identifies novel approaches regarding the application of different specific biomarkers (CD44, Integrins, and EpCAm) for capturing CTCs. These biomarkers can be applied in electrochemical biosensors as a cytodetection strategy for diagnosis of cancerous diseases. Full article
(This article belongs to the Special Issue Biosensing and Diagnosis of Cancer)
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16 pages, 2895 KiB  
Article
Truncated Electrochemical Aptasensor with Enhanced Antifouling Capability for Highly Sensitive Serotonin Detection
by Ziheng Hu, Ruifeng Zhu, Gabriela Figueroa-Miranda, Lei Zhou, Lingyan Feng, Andreas Offenhäusser and Dirk Mayer
Biosensors 2023, 13(9), 881; https://doi.org/10.3390/bios13090881 - 11 Sep 2023
Cited by 2 | Viewed by 1261
Abstract
Accurate determination of serotonin (ST) provides insight into neurological processes and enables applications in clinical diagnostics of brain diseases. Herein, we present an electrochemical aptasensor based on truncated DNA aptamers and a polyethylene glycol (PEG) molecule-functionalized sensing interface for highly sensitive and selective [...] Read more.
Accurate determination of serotonin (ST) provides insight into neurological processes and enables applications in clinical diagnostics of brain diseases. Herein, we present an electrochemical aptasensor based on truncated DNA aptamers and a polyethylene glycol (PEG) molecule-functionalized sensing interface for highly sensitive and selective ST detection. The truncated aptamers have a small size and adopt a stable stem-loop configuration, which improves the accessibility of the aptamer for the analyte and enhances the sensitivity of the aptasensor. Upon target binding, these aptamers perform a conformational change, leading to a variation in the Faraday current of the redox tag, which was recorded by square wave voltammetry (SWV). Using PEG as blocking molecules minimizes nonspecific adsorption of other interfering molecules and thus endows an enhanced antifouling ability. The proposed electrochemical aptamer sensor showed a wide range of detection lasting from 0.1 nM to 1000 nM with a low limit of detection of 0.14 nM. Owing to the unique properties of aptamer receptors, the aptasensor also exhibits high selectivity and stability. Furthermore, with the reduced unspecific adsorption, assaying of ST in human serum and artificial cerebrospinal fluid (aCSF) showed excellent performance. The reported strategy of utilizing antifouling PEG describes a novel approach to building antifouling aptasensors and holds great potential for neurochemical investigations and clinical diagnosis. Full article
(This article belongs to the Special Issue Current Challenges and Breakthroughs in Electrochemical Aptamer-Based Sensors)
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24 pages, 5230 KiB  
Review
SERS-Based Optical Nanobiosensors for the Detection of Alzheimer’s Disease
by Feng Gao, Fang Li, Jianhao Wang, Hang Yu, Xiang Li, Hongyu Chen, Jiabei Wang, Dongdong Qin, Yiyi Li, Songyan Liu, Xi Zhang and Zhi-Hao Wang
Biosensors 2023, 13(9), 880; https://doi.org/10.3390/bios13090880 - 11 Sep 2023
Cited by 1 | Viewed by 1998
Abstract
Alzheimer’s disease (AD) is a leading cause of dementia, impacting millions worldwide. However, its complex neuropathologic features and heterogeneous pathophysiology present significant challenges for diagnosis and treatment. To address the urgent need for early AD diagnosis, this review focuses on surface-enhanced Raman scattering [...] Read more.
Alzheimer’s disease (AD) is a leading cause of dementia, impacting millions worldwide. However, its complex neuropathologic features and heterogeneous pathophysiology present significant challenges for diagnosis and treatment. To address the urgent need for early AD diagnosis, this review focuses on surface-enhanced Raman scattering (SERS)-based biosensors, leveraging the excellent optical properties of nanomaterials to enhance detection performance. These highly sensitive and noninvasive biosensors offer opportunities for biomarker-driven clinical diagnostics and precision medicine. The review highlights various types of SERS-based biosensors targeting AD biomarkers, discussing their potential applications and contributions to AD diagnosis. Specific details about nanomaterials and targeted AD biomarkers are provided. Furthermore, the future research directions and challenges for improving AD marker detection using SERS sensors are outlined. Full article
(This article belongs to the Section Optical and Photonic Biosensors)
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12 pages, 3229 KiB  
Article
Protein Identification and Quantification Using Porous Silicon Arrays, Optical Measurements, and Machine Learning
by Simon J. Ward, Tengfei Cao, Xiang Zhou, Catie Chang and Sharon M. Weiss
Biosensors 2023, 13(9), 879; https://doi.org/10.3390/bios13090879 - 09 Sep 2023
Viewed by 1456
Abstract
We report a versatile platform based on an array of porous silicon (PSi) thin films that can identify analytes based on their physical and chemical properties without the use of specific capture agents. The ability of this system to reproducibly classify, quantify, and [...] Read more.
We report a versatile platform based on an array of porous silicon (PSi) thin films that can identify analytes based on their physical and chemical properties without the use of specific capture agents. The ability of this system to reproducibly classify, quantify, and discriminate three proteins separately is demonstrated by probing the reflectance of PSi array elements with a unique combination of pore size and buffer pH, and by analyzing the optical signals using machine learning. Protein identification and discrimination are reported over a concentration range of two orders of magnitude. This work represents a significant first step towards a low-cost, simple, versatile, and robust sensor platform that is able to detect biomolecules without the added expense and limitations of using capture agents. Full article
(This article belongs to the Special Issue Advances in Biosensors Based on Reflectometry)
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14 pages, 970 KiB  
Article
Rapid and Versatile Biosensing of Liposome Encapsulation Efficiency Using Electrical Conductivity Sensor
by Tatiane Melo Pereira, Cínthia Caetano Bonatto and Luciano Paulino Silva
Biosensors 2023, 13(9), 878; https://doi.org/10.3390/bios13090878 - 08 Sep 2023
Viewed by 1921
Abstract
Liposomes are prominent nanosystems for drug delivery, with potential extending beyond isolated drugs. Ethanol-aqueous plant extracts can be encapsulated within liposomes to protect bioactive compounds (secondary metabolites) from rapid oxidation and enable sustained release. Determining which compound classes are present in each extract [...] Read more.
Liposomes are prominent nanosystems for drug delivery, with potential extending beyond isolated drugs. Ethanol-aqueous plant extracts can be encapsulated within liposomes to protect bioactive compounds (secondary metabolites) from rapid oxidation and enable sustained release. Determining which compound classes are present in each extract and the encapsulation efficiency (EE) of these extracts in liposomes is crucial for nanocarrier functionality. This involves assessing the ratio of bioactive substances within liposomes to the total content. However, quantifying EE for non-isolated compounds poses challenges due to the need for advanced analytical equipment and biosensing approaches. This study introduces an innovative method for EE quantification, using a conductivity electrode (k = 0.842/cm) to establish an EE biosensing technology. By correlating dynamic light scattering (DLS), zeta potential (ZP), and electrical conductivity (Cnd) data with the conductivity meter’s calibration curve, a robust relationship between the free extract concentration and Cnd (r2 ≥ 0.950) was established. Lavender-loaded liposomes demonstrated an EE of 56.33%, while wormwood and oregano formulations exhibited high EEs of 94.33% and 91.70%, respectively. In contrast, sage-loaded liposomes exhibited an inadequate EE, encapsulating only approximately 0.57% of the extract. The straightforward quantification of the free extract within liposome formulations, compared to more complex approaches, could facilitate EE determination and support future characterizations. Full article
(This article belongs to the Special Issue Advances in Molecular Biosensors)
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18 pages, 6546 KiB  
Article
Molecularly Imprinted Polymer-Coated CdTe Quantum Dots for Fluorometric Detection of Sulfonamide Antibiotics in Food Samples
by Bianca Mortari, Sabir Khan, Ademar Wong and Maria Del Pilar Taboada Sotomayor
Biosensors 2023, 13(9), 877; https://doi.org/10.3390/bios13090877 - 08 Sep 2023
Cited by 1 | Viewed by 1347
Abstract
This work reports the development and application of a highly selective core@shell-based quantum dot–molecularly imprinted polymer (QD@MIP) sensor for the detection of sulfadiazine (SDZ)—an antibiotic which belongs to the sulfonamide family. The synthesis of the smart material or MIP (molecularly imprinted polymer) was [...] Read more.
This work reports the development and application of a highly selective core@shell-based quantum dot–molecularly imprinted polymer (QD@MIP) sensor for the detection of sulfadiazine (SDZ)—an antibiotic which belongs to the sulfonamide family. The synthesis of the smart material or MIP (molecularly imprinted polymer) was carried out by a precipitation method directly on the quantum dot surface, which played the role of a fluorescent probe in the optical sensor. The synthesized polymer was characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. Fluorescence experiments were performed in order to evaluate the effects of pH, interaction time of the QD@MIP with the analyte and SDZ concentration in different matrices. Under optimized conditions, a linear concentration range of 10.0–60.0 ppm and a limit of detection of 3.33 ppm were obtained. The repeatability and reproducibility of the proposed QD@MIP were evaluated in terms of the RSD, where RSD values of less than 5% were obtained in both tests. Selectivity studies were carried out in the presence of four possible interfering substances with quenching properties, and the signals obtained for these interferents confirmed the excellent selectivity of the proposed sensor; the imprinting factor value obtained for SDZ was 1.64. Finally, the proposed sensor was applied in real animal-based food samples using a spiked concentration of SDZ, where the recovery values obtained were above 90% (experiments were performed in triplicate). Full article
(This article belongs to the Special Issue Trends in Fluorescent and Bioluminescent Biosensors)
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17 pages, 4182 KiB  
Article
Development of a High-Accuracy, Low-Cost, and Portable Fluorometer with Smartphone Application for the Detection of Urinary Albumin towards the Early Screening of Chronic Kidney and Renal Diseases
by Visarute Pinrod, Wireeya Chawjiraphan, Khoonsake Segkhoonthod, Kriangkai Hanchaisri, Phornpol Tantiwathanapong, Preedee Pinpradup, Thitirat Putnin, Dechnarong Pimalai, Kiatnida Treerattrakoon, Ubon Cha’on, Sirirat Anutrakulchai and Deanpen Japrung
Biosensors 2023, 13(9), 876; https://doi.org/10.3390/bios13090876 - 08 Sep 2023
Viewed by 2200
Abstract
This study presents the development of a portable fluorometer with a smartphone application designed to facilitate the early screening of chronic kidney and renal diseases by enabling the sensitive detection of urinary albumin. Utilizing a fluorescence-based aptasensor, the device achieved a linear calibration [...] Read more.
This study presents the development of a portable fluorometer with a smartphone application designed to facilitate the early screening of chronic kidney and renal diseases by enabling the sensitive detection of urinary albumin. Utilizing a fluorescence-based aptasensor, the device achieved a linear calibration curve (0.001–1.5 mg/mL) with a linearity of up to 0.98022 and a detection limit of 0.203 µg/mL for human serum albumin (HSA). The analysis of 130 urine samples demonstrated comparable performance between this study’s fluorometer, a commercial fluorometer, and the standard automated method. These findings validate the feasibility of the portable fluorometer and aptasensor combination as a reliable instrument for the sensitive and specific measurement of HSA in urine samples. Moreover, the fluorometer’s portability offers potential applications in portable point-of-care testing, enhancing its utility in clinical settings for early disease screening. Full article
(This article belongs to the Section Biosensors and Healthcare)
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9 pages, 3235 KiB  
Communication
Extraordinarily Stable Hairpin-Based Biosensors for Rapid Detection of DNA Ligases
by Ziang Wu, Roujuan Kou, Kun Ni, Rui Song, Yuxuan Li, Tianhu Li and Hao Zhang
Biosensors 2023, 13(9), 875; https://doi.org/10.3390/bios13090875 - 08 Sep 2023
Viewed by 1100
Abstract
DNA ligases are essential enzymes involved in DNA replication and repair processes in all organisms. These enzymes seal DNA breaks by catalyzing the formation of phosphodiester bonds between juxtaposed 5′ phosphate and 3′ hydroxyl termini in double-stranded DNA. In addition to their critical [...] Read more.
DNA ligases are essential enzymes involved in DNA replication and repair processes in all organisms. These enzymes seal DNA breaks by catalyzing the formation of phosphodiester bonds between juxtaposed 5′ phosphate and 3′ hydroxyl termini in double-stranded DNA. In addition to their critical roles in maintaining genomic integrity, DNA ligases have been recently identified as diagnostic biomarkers for several types of cancers and recognized as potential drug targets for the treatment of various diseases. Although DNA ligases are significant in basic research and medical applications, developing strategies for efficiently detecting and precisely quantifying these crucial enzymes is still challenging. Here, we report our design and fabrication of a highly sensitive and specific biosensor in which a stable DNA hairpin is utilized to stimulate the generation of fluorescence signals. This probe is verified to be stable under a wide range of experimental conditions and exhibits promising performance in detecting DNA ligases. We anticipate that this hairpin-based biosensor will significantly benefit the development of new targeting strategies and diagnostic tools for certain diseases. Full article
(This article belongs to the Section Biosensor and Bioelectronic Devices)
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12 pages, 1565 KiB  
Article
Cost-Effective Modular Biosensor for SARS-CoV-2 and Influenza A Detection
by Andrew Murray, Julio Ojeda, Omar El Merhebi, Percy Calvo-Marzal, Yulia Gerasimova and Karin Chumbimuni-Torres
Biosensors 2023, 13(9), 874; https://doi.org/10.3390/bios13090874 - 07 Sep 2023
Cited by 2 | Viewed by 1250
Abstract
A modular, multi-purpose, and cost-effective electrochemical biosensor based on a five-stranded four-way junction (5S-4WJ) system was developed for SARS-CoV-2 (genes S and N) and Influenza A virus (gene M) detection. The 5S-4WJ structure consists of an electrode-immobilized universal stem-loop (USL) strand, two auxiliary [...] Read more.
A modular, multi-purpose, and cost-effective electrochemical biosensor based on a five-stranded four-way junction (5S-4WJ) system was developed for SARS-CoV-2 (genes S and N) and Influenza A virus (gene M) detection. The 5S-4WJ structure consists of an electrode-immobilized universal stem-loop (USL) strand, two auxiliary DNA strands, and a universal methylene blue redox strand (UMeB). This design allows for the detection of specific nucleic acid sequences using square wave voltammetry (SWV). The sequence-specific auxiliary DNA strands (m and f) ensure selectivity of the biosensor for target recognition utilizing the same USL and UMeB components. An important feature of this biosensor is the ability to reuse the USL-modified electrodes to detect the same or alternative targets in new samples. This is accomplished by a simple procedure involving rinsing the electrodes with water to disrupt the 5S-4WJ structure and subsequent re-hybridization of the USL strand with the appropriate set of strands for a new analysis. The biosensor exhibited minimal loss in signal after rehybridization, demonstrating its potential as a viable multiplex assay for both current and future pathogens, with a low limit of quantification (LOQ) of as low as 17 pM. Full article
(This article belongs to the Special Issue Advanced Functional Materials for Electrochemical Sensor and Biosensor Applications)
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15 pages, 2879 KiB  
Article
A Methylene Blue-Enhanced Nanostructured Electrochemical Immunosensor for H-FABP Myocardial Injury Biomarker
by Cecília Maciel Prado, Paula Angélica Burgos Ferreira, Lucas Alves de Lima, Erika Ketlem Gomes Trindade and Rosa Fireman Dutra
Biosensors 2023, 13(9), 873; https://doi.org/10.3390/bios13090873 - 07 Sep 2023
Viewed by 1182
Abstract
A sensitive electrochemical immunosensor for the detection of the heart-type fatty acid binding protein (HFABP), an earlier biomarker for acute myocardial infarction than Troponins, is described. The sensing platform was enhanced with methylene blue (MB) redox coupled to carbon nanotubes (CNT) assembled on [...] Read more.
A sensitive electrochemical immunosensor for the detection of the heart-type fatty acid binding protein (HFABP), an earlier biomarker for acute myocardial infarction than Troponins, is described. The sensing platform was enhanced with methylene blue (MB) redox coupled to carbon nanotubes (CNT) assembled on a polymer film of polythionine (PTh). For this strategy, monomers of thionine rich in amine groups were electrosynthesized by cyclic voltammetry on the immunosensor’s gold surface, forming an electroactive film with excellent electron transfer capacity. Stepwise sensor surface preparation was electrochemically characterized at each step and scanning electronic microscopy was carried out showing all the preparation steps. The assembled sensor platform combines MB and PTh in a synergism, allowing sensitive detection of the H-FABP in a linear response from 3.0 to 25.0 ng∙mL−1 with a limit of detection of 1.47 ng∙mL−1 HFABP that is similar to the clinical level range for diagnostics. H-FABP is a newer powerful biomarker for distinguishing between unstable angina and acute myocardial infarction. Full article
(This article belongs to the Special Issue Nanomaterial Based Biosensors for Biomedical Applications)
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24 pages, 18152 KiB  
Review
Skin-Contact Triboelectric Nanogenerator for Energy Harvesting and Motion Sensing: Principles, Challenges, and Perspectives
by Ali Matin Nazar, Reza Mohsenian, Arash Rayegani, Mohammadamin Shadfar and Pengcheng Jiao
Biosensors 2023, 13(9), 872; https://doi.org/10.3390/bios13090872 - 06 Sep 2023
Cited by 3 | Viewed by 2217
Abstract
Energy harvesting has become an increasingly important field of research as the demand for portable and wearable devices continues to grow. Skin-contact triboelectric nanogenerator (TENG) technology has emerged as a promising solution for energy harvesting and motion sensing. This review paper provides a [...] Read more.
Energy harvesting has become an increasingly important field of research as the demand for portable and wearable devices continues to grow. Skin-contact triboelectric nanogenerator (TENG) technology has emerged as a promising solution for energy harvesting and motion sensing. This review paper provides a detailed overview of skin-contact TENG technology, covering its principles, challenges, and perspectives. The introduction begins by defining skin-contact TENG and explaining the importance of energy harvesting and motion sensing. The principles of skin-contact TENG are explored, including the triboelectric effect and the materials used for energy harvesting. The working mechanism of skin-contact TENG is also discussed. This study then moves onto the applications of skin-contact TENG, focusing on energy harvesting for wearable devices and motion sensing for healthcare monitoring. Furthermore, the integration of skin-contact TENG technology with other technologies is discussed to highlight its versatility. The challenges in skin-contact TENG technology are then highlighted, which include sensitivity to environmental factors, such as humidity and temperature, biocompatibility and safety concerns, and durability and reliability issues. This section of the paper provides a comprehensive evaluation of the technological limitations that must be considered when designing skin-contact TENGs. In the Perspectives and Future Directions section, this review paper highlights various advancements in materials and design, as well as the potential for commercialization. Additionally, the potential impact of skin-contact TENG technology on the energy and healthcare industries is discussed. Full article
(This article belongs to the Section Wearable Biosensors)
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9 pages, 5665 KiB  
Communication
Microlens-Assisted Light-Scattering Imaging of Plasmonic Nanoparticles at the Single Particle Level
by Pengcheng Zhang, Tingting Zhan, Sha Xue and Hui Yang
Biosensors 2023, 13(9), 871; https://doi.org/10.3390/bios13090871 - 06 Sep 2023
Viewed by 1004
Abstract
We present a microlens-assisted imaging approach to record the scattering light of plasmonic nanoparticles at the single particle level. The microlens can significantly enhance the backscattering of visible light from individual plasmonic nanoparticles by several dozen folds, and single gold nanoparticles with a [...] Read more.
We present a microlens-assisted imaging approach to record the scattering light of plasmonic nanoparticles at the single particle level. The microlens can significantly enhance the backscattering of visible light from individual plasmonic nanoparticles by several dozen folds, and single gold nanoparticles with a diameter as low as 60 nm can be imaged under a conventional optical microscope. This can benefit from a significant increase in the scattering intensity afforded by the microlens, meaning that the imaging of gold nanoparticles at a high temporal resolution (up to 5000 Hz) can be achieved, which is fast enough to record single particle adhesion events on the substrate. This research presents a fast and efficient means of acquiring scattering light from plasmonic nanoparticles, which has great potential to develop plasmonic nanoparticle-based biosensors and investigate a wide range of plasmonic nanoparticle-based fast interaction processes. Full article
(This article belongs to the Special Issue Nanophotonic Approaches to Biosensing and Bioimaging Applications)
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11 pages, 2584 KiB  
Review
Two Decades of Arrayed Imaging Reflectometry for Sensitive, High-Throughput Biosensing
by Gabrielle Kosoy and Benjamin L. Miller
Biosensors 2023, 13(9), 870; https://doi.org/10.3390/bios13090870 - 05 Sep 2023
Cited by 1 | Viewed by 3159
Abstract
Arrayed imaging reflectometry (AIR), first introduced in 2004, is a thin-film interference sensor technique that optimizes optical properties (angle of incidence, polarization, substrate refractive index, and thickness) to create a condition of total destructive interference at the surface of a silicon substrate. The [...] Read more.
Arrayed imaging reflectometry (AIR), first introduced in 2004, is a thin-film interference sensor technique that optimizes optical properties (angle of incidence, polarization, substrate refractive index, and thickness) to create a condition of total destructive interference at the surface of a silicon substrate. The advantages of AIR are its sensitivity, dynamic range, multiplex capability, and high-throughput compatibility. AIR has been used for the detection of antibodies against coronaviruses, influenza viruses, Staphylococcus aureus, and human autoantigens. It has also shown utility in detection of cytokines, with sensitivity comparable to bead-based and ELISA assays. Not limited to antibodies or antigens, mixed aptamer and protein arrays as well as glycan arrays have been employed in AIR for differentiating influenza strains. Mixed arrays using direct and competitive inhibition assays have enabled simultaneous measurement of cytokines and small molecules. Finally, AIR has also been used to measure affinity constants, kinetic and at equilibrium. In this review, we give an overview of AIR biosensing technologies and present the latest AIR advances. Full article
(This article belongs to the Special Issue Advances in Biosensors Based on Reflectometry)
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12 pages, 1631 KiB  
Article
Irregular Antibody Screening Using a Microdroplet Platform
by Ding-Ping Chen, Pei-Yu Wu and Yen-Heng Lin
Biosensors 2023, 13(9), 869; https://doi.org/10.3390/bios13090869 - 04 Sep 2023
Viewed by 1565
Abstract
The screening procedure for antibodies is considered the most tedious among the three pretransfusion operations, i.e., ABO and Rhesus (Rh) typing, irregular antibody screening/identification, and crossmatching tests. The commonly used screening method for irregular antibodies in clinics at present is a manual polybrene [...] Read more.
The screening procedure for antibodies is considered the most tedious among the three pretransfusion operations, i.e., ABO and Rhesus (Rh) typing, irregular antibody screening/identification, and crossmatching tests. The commonly used screening method for irregular antibodies in clinics at present is a manual polybrene test (MP). The MP test involves numerous reagent replacement and centrifuge procedures, and the sample volume is expected to be relatively less. Herein, screening red blood cells (RBCs) and serum irregular antibodies are encapsulated in microdroplets with a diameter of ~300 μm for a hemagglutination reaction. Owing to the advantage of spatial limitation in microdroplets, screening RBCs and irregular antibodies can be directly agglutinated, thereby eliminating the need for centrifugation and the addition of reagents to promote agglutination, as required by the MP method. Furthermore, the results for a large number of repeated tests can be concurrently obtained, further simplifying the steps of irregular antibody screening and increasing accuracy. Eight irregular antibodies are screened using the proposed platform, and the results are consistent with the MP method. Moreover, the volume of blood samples and antibodies can be reduced to 10 μL and 5 μL, respectively, which is ten times less than that using the MP method. Full article
(This article belongs to the Special Issue Microfluidic Biochips and Their Biomedical Applications)
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