生物传感器的应用研究进展

生物传感器是一门由生物、化学、物理、医学、电子技术等多种学科互相渗透成长起来的高新技术 ,是一种将生物感应元件的专一性与一个能够产生和待测物浓度成比例的信号传导器结合起来的分析装置。由于其具有选择性好、灵敏度高、分析速度快、成本低、能在复杂体系中进行在线连续监测的特点 ,已在生物、医学、环境监测、食品、医药、及军事医学等领域显示出广阔的应用前景 ,引起了世界各国的极大关注。综述了生物传感器的基本原理、分类、特点及在环境监测、食品分析、生物医学和军事上的应用 ,并对其发展前景进行了展望。     

Biosensors

Biosensors are analytical devices that respond selectively to analytes in an appropriate sample and convert their concentration into an electrical signal via a combination of a biological recognition system and an electrochemical, optical or other transducer. Such devices will find application in medicine, agriculture, environmental monitoring and the bioprocessing industries. The last few years have seen great advances in the design of sensor architectures, the marriage of biological systems with monolithic silicon and optical technologies, the development of effective electron-transfer systems and the configuration of direct immunosensors. Recent progress in these areas has already led to the introduction of new-generation biosensors into the competitive diagnostics market place.     

Biological and technical challenges for implementation of yeast-based biosensors

Biosensors are low-cost and low-maintenance alternatives to conventional analytical techniques for biomedical, industrial and environmental applications. Biosensors based on whole microorganisms can be genetically engineered to attain high sensitivity and specificity for the detection of selected analytes. While bacteria-based biosensors have been extensively reported, there is a recent interest in yeast-based biosensors, combining the microbial with the eukaryotic advantages, including possession of specific receptors, stability and high robustness. Here, we describe recently reported yeast-based biosensors highlighting their biological and technical features together with their status of development, that is, laboratory or prototype. Notably, most yeast-based biosensors are still in the early developmental stage, with only a few prototypes tested for real applications. Open challenges, including systematic use of advanced molecular and biotechnological tools, bioprospecting, and implementation of yeast-based biosensors in electrochemical setup, are discussed to find possible solutions for overcoming bottlenecks and promote real-world application of yeast-based biosensors.     

检测食源性致病菌的生物传感器

  大肠埃希氏菌、李斯特氏菌和鼠伤寒沙门氏菌等几种食源性致病菌不仅威胁到人们的 生命安全,还会造成巨大的社会经济损失.生物传感器是将生物识别元件和信号转换元件紧 密结合,从而检测目标化合物的分析装置.生物传感器在致病菌检测方面具有分析速度快、 灵敏度高、专一性强等特点;可分为光学式、电化学式、压电式生物传感器等;在检测食源 性致病菌方面生物传感器表现出能够满足实际应用的发展潜力,但是生物传感器目前仍面临 并需要解决一些问题,这也是生物传感器从实验室到市场如此缓慢的原因.最后提出了实际 检测应用中对生物传感器的要求.     

Biosensors: current applications and future potential

Biological molecules such as enzymes and antibodies display a unique capacity to recognize and respond to other molecules in a way which can be exploited in the development of analytical devices. In a biosensor, the biological recognition system creates a physiochemical change proximal to a suitable transducer and thereby converts the concentration of the analyte into a quantifiable electrical signal. The design and construction of these devices requires an imaginative combination of biological, chemical, physical and engineering disciplines. Biosensors will find application in a variety of analytical fields.     

Direct biologically based biosensing of dynamic physiological function

Dynamic regulation of biological systems requires real-time assessment of relevant physiological needs. Biosensors, which transduce biological actions or reactions into signals amenable to processing, are well suited for such monitoring. Typically, in vivo biosensors approximate physiological function via the measurement of surrogate signals. The alternative approach presented here would be to use biologically based biosensors for the direct measurement of physiological activity via functional integration of relevant governing inputs. We show that an implanted excitable-tissue biosensor (excitable cardiac tissue) can be used as a real-time, integrated bioprocessor to analyze the complex inputs regulating a dynamic physiological variable (heart rate). This approach offers the potential for long-term biologically tuned quantification of endogenous physiological function.     

Biosensor technology: technology push versus market pull

Biosensor technology is based on a specific biological recognition element in combination with a transducer for signal processing. Since its inception, biosensors have been expected to play a significant analytical role in medicine, agriculture, food safety, homeland security, environmental and industrial monitoring. However, the commercialization of biosensor technology has significantly lagged behind the research output as reflected by a plethora of publications and patenting activities. The rationale behind the slow and limited technology transfer could be attributed to cost considerations and some key technical barriers. Analytical chemistry has changed considerably, driven by automation, miniaturization, and system integration with high throughput for multiple tasks. Such requirements pose a great challenge in biosensor technology which is often designed to detect one single or a few target analytes. Successful biosensors must be versatile to support interchangeable biorecognition elements, and in addition miniaturization must be feasible to allow automation for parallel sensing with ease of operation at a competitive cost. A significant upfront investment in research and development is a prerequisite in the commercialization of biosensors. The progress in such endeavors is incremental with limited success, thus, the market entry for a new venture is very difficult unless a niche product can be developed with a considerable market volume.     

Antibody production,design and use for biosensor-based applications

Currently, the reliable detection and quantification of a multitude of different analytes is crucial in many applications and settings. Biosensors have revolutionised diagnostics for use in point-of-care testing (POC), the detection of food and environmental contaminants, biological warfare agents, illicit drugs and human/animal disease markers. Antibodies continue to play a pivotal role in many sensor devices due to their exquisite specificity for their cognate antigens. In this review current biosensor platforms employing antibodies for molecular recognition are briefly described. The use of molecular biological techniques for the generation and improvement of antibodies is critically examined. Such recombinant antibodies possess improved attributes for use in biosensor development in terms of design, stability, affinity and specificity.     

Multi-analyte surface plasmon resonance biosensing

Surface plasmon resonance (SPR) biosensors are affinity sensing devices exploiting a special mode of electromagnetic field-surface plasmon-polariton-to detect the binding of analyte molecules from a liquid sample to biomolecular recognition elements immobilized on the surface of the sensor. In this paper, we review advances of SPR biosensor technology towards detection systems for the simultaneous detection of multiple analytes (multi-analyte detection). In addition, we report application of a recently developed multichannel SPR sensor based on spectroscopy of surface plasmons and wavelength division multiplexing of sensing channels to multi-analyte detection.     

A portable surface plasmon resonance sensor system for real-time monitoring of small to large analytes

Many environmental applications exist for biosensors capable of providing real-time analyses. One pressing current need is monitoring for agents of chemical- and bio-terrorism. These applications require systems that can rapidly detect small organics including nerve agents, toxic proteins, viruses, spores and whole microbes. A second area of application is monitoring for environmental pollutants. Processing of grab samples through chemical laboratories requires significant time delays in the analyses, preventing the rapid mapping and cleanup of chemical spills. The current state of development of miniaturized, integrated surface plasmon resonance (SPR) sensor elements has allowed for the development of inexpensive, portable biosensor systems capable of the simultaneous analysis of multiple analytes. Most of the detection protocols make use of antibodies immobilized on the sensor surface. The Spreeta 2000 SPR biosensor elements manufactured by Texas Instruments provide three channels for each sensor element in the system. A temperature-controlled two-element system that monitors for six analytes is currently in use, and development of an eight element sensor system capable of monitoring up to 24 different analytes will be completed in the near future. Protein toxins can be directly detected and quantified in the low picomolar range. Elimination of false positives and increased sensitivity is provided by secondary antibodies with specificity for different target epitopes, and by sensor element redundancy. Inclusion of more than a single amplification step can push the sensitivity of toxic protein detection to femtomolar levels. The same types of direct detection and amplification protocols are used to monitor for viruses and whole bacteria or spores. Special protocols are required for the detection of small molecules. Either a competition type assay where the presence of analyte inhibits the binding of antibodies to surface-immobilized analyte, or a displacement assay, where antibodies bound to analyte on the sensor surface are displaced by free analyte, can be used. The small molecule detection assays vary in sensitivity from the low micromolar range to the high picomolar.

     

A portable surface plasmon resonance sensor system for real-time monitoring of small to large analytes

Many environmental applications exist for biosensors capable of providing real-time analyses. One pressing current need is monitoring for agents of chemical- and bio-terrorism. These applications require systems that can rapidly detect small organics including nerve agents, toxic proteins, viruses, spores and whole microbes. A second area of application is monitoring for environmental pollutants. Processing of grab samples through chemical laboratories requires significant time delays in the analyses, preventing the rapid mapping and cleanup of chemical spills. The current state of development of miniaturized, integrated surface plasmon resonance (SPR) sensor elements has allowed for the development of inexpensive, portable biosensor systems capable of the simultaneous analysis of multiple analytes. Most of the detection protocols make use of antibodies immobilized on the sensor surface. The Spreeta 2000 SPR biosensor elements manufactured by Texas Instruments provide three channels for each sensor element in the system. A temperature-controlled two-element system that monitors for six analytes is currently in use, and development of an eight element sensor system capable of monitoring up to 24 different analytes will be completed in the near future. Protein toxins can be directly detected and quantified in the low picomolar range. Elimination of false positives and increased sensitivity is provided by secondary antibodies with specificity for different target epitopes, and by sensor element redundancy. Inclusion of more than a single amplification step can push the sensitivity of toxic protein detection to femtomolar levels. The same types of direct detection and amplification protocols are used to monitor for viruses and whole bacteria or spores. Special protocols are required for the detection of small molecules. Either a competition type assay where the presence of analyte inhibits the binding of antibodies to surface-immobilized analyte, or a displacement assay, where antibodies bound to analyte on the sensor surface are displaced by free analyte, can be used. The small molecule detection assays vary in sensitivity from the low micromolar range to the high picomolar.     

Electrochemical DNA biosensor for screening of chlorinated benzene pollutants

In this work, an electrochemical DNA biosensor based on double-stranded DNA modified Au electrode (dsDNA/Au) was proposed for the rapid screening and detection of chlorinated benzenes pollutants, in which redox-active methylene blue (MB) was used to amplify the interaction between dsDNA and the target analyte. Using hexachlorobenzene (HCB) as a model analyte of chlorinated benzenes, the biosensor demonstrated a linear response with the logarithm of HCB concentrations from 100 pmol L(-1) to 100 nmol L(-1). The obtained detection limit was 30 pmol L(-1), which was remarkably superior to other biosensors. The interaction mechanism of the biosensor with HCB was proposed based on systematical characterization by cyclic voltammetry (CV), differential pulse voltammetry (DPV), UV-vis spectrometry and electrochemical quartz crystal microbalance (EQCM). Further studies revealed that the biosensor could screen chlorinated benzenes in the presence of 100 fold amount of other co-existing chemicals (ethyl acetate and sodium oxalate, etc.), and the response signal of the biosensors for different chlorinated benzenes was correlative to their respective toxicity. The proposed biosensor proved to be a promising "alarm" tool for rapid screening of chlorinated benzenes in real water samples.     

In vitro selection of signaling aptamers

Reagentless biosensors that can directly transduce molecular recognition to optical signals should potentiate the development of sensor arrays for a wide variety of analytes. Nucleic acid aptamers that bind ligands tightly and specifically can be readily selected, but may prove difficult to adapt to biosensor applications. We have therefore attempted to develop selection methods that couple the broad molecular recognition properties of aptamers with signal transduction. Anti-adenosine aptamers were selected from a pool that was skewed to contain very few fluoresceinated uridines. The primary family of aptamers showed a doubling of relative fluorescence intensity at saturating concentrations of a cognate analyte, ATP, and could sense ATP concentrations as low as 25 microM. A single uridine was present in the best signaling aptamer. Surprisingly, other dyes could substitute for fluorescein and still specifically signal the presence of ATP, indicating that the single uridine functioned as a general "switch" for transducing molecular recognition to optical signals.     

Introduction to the principles and applications of biosensors

A biosensor is an analytical device that responds to an analyte in an appropriate sample and interprets its concentration as an electrical signal via a suitable combination of a biological recognition system and an electrochemical transducer. As a result of recent scientific and technological progress, such devices are likely to play an increasingly important role in generating analytical information in all sectors of human endeavour, from medicine to the military. In particular, biosensors will form the basis of cheap, simple devices for acquiring chemical information, bringing sophisticated analytical capabilities to the non-specialist and general public alike. The market opportunities for the rapid exploitation of novel developments in this sector are substantial. Biosensor research is also likely to have a significant impact on the development of modern electronics.     

Development of biosensors for cancer clinical testing

Biosensors are devices that combine a biochemical recognition/binding element (ligand) with a signal conversion unit (transducer). Biosensors are already used for several clinical applications, for example for electrochemical measurement of blood glucose concentrations. Application of biosensors in cancer clinical testing has several potential advantages over other clinical analysis methods including increased assay speed and flexibility, capability for multi-target analyses, automation, reduced costs of diagnostic testing and a potential to bring molecular diagnostic assays to community health care systems and to underserved populations. They have the potential for facilitating Point of Care Testing (POCT), where state-of-the-art molecular analysis is carried out without requiring a state-of-the-art laboratory. However, not many biosensors have been developed for cancer-related testing. One major challenge in harnessing the potential of biosensors is that cancer is a very complex set of diseases. Tumors vary widely in etiology and pathogenesis. Oncologists rely heavily on histological characterization of tumors and a few biomarkers that have demonstrated clinical utility to aid in patient management decisions. New genomic and proteomic molecular tools are being used to profile tumors and produce "molecular signatures." These signatures include genetic and epigenetic signatures, changes in gene expression, protein profiles and post-translational modifications of proteins. These molecular signatures provide new opportunities for utilizing biosensors. Biosensors have enormous potential to deliver the promise of new molecular diagnostic strategies to patients. This article describes some of the basic elements of cancer biology and cancer biomarkers relevant for the development of biosensors for cancer clinical testing, along with the challenges in using this approach.     

Applications of whole-cell bacterial sensors in biotechnology and environmental science

Biosensors have major advantages over chemical or physical analyses with regard to specificity, sensitivity, and portability. Recently, many types of whole-cell bacterial biosensors have been developed using recombinant DNA technology. The bacteria are genetically engineered to respond to the presence of chemicals or physiological stresses by synthesizing a reporter protein, such as luciferase, β-galactosidase, or green fluorescent protein. In addition to an overview of conventional biosensors, this minireview discusses a novel type of biosensor using a photosynthetic bacterium as the sensor strain and the crtA gene, which is responsible for carotenoid synthesis, as the reporter. Since bacteria possess a wide variety of stress-response mechanisms, including antioxidation, heat-shock responses, nutrient-starvation, and membrane-damage responses, DNA response elements for several stress-response proteins can be fused with various reporter genes to construct a versatile set of bacterial biosensors for a variety of analytes. Portable biosensors for on-site monitoring have been developed using a freeze-dried biosensing strain, and cell array biosensors have been designed for high-throughput analysis. Moreover, in the future, the use of single-cell biosensors will permit detailed analyses of samples. Signals from such sensors could be detected with digital imaging, epifluorescence microscopy, and/or flow cytometry.     

Biosensors for process control

Biosensors have been extensively studied during the last 20 years, and a myriad of laboratory biosensors have been developed. Improvements are required in biosensor design and performance before they become widely accepted in industrial process monitoring. However, as the biotechnology industry expands, biosensors may become more acceptable because, despite their limitations, they are the only devices capable of delivering the information required.     

Insight of smart biosensors for COVID-19: A review

The review discusses the diagnostic application of biosensors as point-of-care devices in the COVID-19 pandemic. Biosensors are important analytical tools that can be used for the robust and effective detection of infectious diseases in real-time. In this current scenario, the utilization of smart, efficient biosensors for COVID-19 detection is increasing and we have included a few smart biosensors such as smart and intelligent based biosensors, plasmonic biosensors, field effect transistor (FET) biosensors, smart optical biosensors, surface enhanced Raman scattering (SERS) biosensor, screen printed electrode (SPE)-based biosensor, molecular imprinted polymer (MIP)-based biosensor, MXene-based biosensor and metal–organic frame smart sensor. Their significance as well as the benefits and drawbacks of each kind of smart sensor are mentioned in depth. Furthermore, we have compiled a list of various biosensors which have been developed across the globe for COVID-19 and have shown promise as commercial detection devices. Significant challenges in the development of effective diagnostic methods are discussed and recommendations have been made for better diagnostic outcomes to manage the ongoing pandemic effectively.