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Li Q, Dou L, Zhang Y, Luo L, Yang H, Wen K, Yu X, Shen J, Wang Z. A comprehensive review on the detection of Staphylococcus aureus enterotoxins in food samples. Compr Rev Food Sci Food Saf 2024; 23:e13264. [PMID: 38284582 DOI: 10.1111/1541-4337.13264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 10/12/2023] [Accepted: 10/15/2023] [Indexed: 01/30/2024]
Abstract
Staphylococcal enterotoxins (SEs), the major virulence factors of Staphylococcus aureus, cause a wide range of food poisoning and seriously threaten human health by infiltrating the food supply chain at different phases of manufacture, processes, distribution, and market. The significant prevalence of Staphylococcus aureus calls for efficient, fast, and sensitive methods for the early detection of SEs. Here, we provide a comprehensive review of the hazards of SEs in contaminated food, the characteristic and worldwide regulations of SEs, and various detection methods for SEs with extensive comparison and discussion of benefits and drawbacks, mainly including biological detection, genetic detection, and mass spectrometry detection and biosensors. We highlight the biosensors for the screening purpose of SEs, which are classified according to different recognition elements such as antibodies, aptamers, molecularly imprinted polymers, T-cell receptors, and transducers such as optical, electrochemical, and piezoelectric biosensors. We analyzed challenges of biosensors for the monitoring of SEs and conclude the trends for the development of novel biosensors should pay attention to improve samples pretreatment efficiency, employ innovative nanomaterials, and develop portable instruments. This review provides new information and insightful commentary, important to the development and innovation of further detection methods for SEs in food samples.
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Affiliation(s)
- Qing Li
- National Key Laboratory of Veterinary Public Health safety, College of Veterinary Medicine China Agricultural University, Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, and Beijing Laboratory for Food Quality and Safety, Beijing, China
| | - Leina Dou
- National Key Laboratory of Veterinary Public Health safety, College of Veterinary Medicine China Agricultural University, Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, and Beijing Laboratory for Food Quality and Safety, Beijing, China
| | - Yingjie Zhang
- National Key Laboratory of Veterinary Public Health safety, College of Veterinary Medicine China Agricultural University, Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, and Beijing Laboratory for Food Quality and Safety, Beijing, China
| | - Liang Luo
- National Key Laboratory of Veterinary Public Health safety, College of Veterinary Medicine China Agricultural University, Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, and Beijing Laboratory for Food Quality and Safety, Beijing, China
| | - Huijuan Yang
- National Key Laboratory of Veterinary Public Health safety, College of Veterinary Medicine China Agricultural University, Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, and Beijing Laboratory for Food Quality and Safety, Beijing, China
| | - Kai Wen
- National Key Laboratory of Veterinary Public Health safety, College of Veterinary Medicine China Agricultural University, Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, and Beijing Laboratory for Food Quality and Safety, Beijing, China
| | - Xuezhi Yu
- National Key Laboratory of Veterinary Public Health safety, College of Veterinary Medicine China Agricultural University, Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, and Beijing Laboratory for Food Quality and Safety, Beijing, China
| | - Jianzhong Shen
- National Key Laboratory of Veterinary Public Health safety, College of Veterinary Medicine China Agricultural University, Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, and Beijing Laboratory for Food Quality and Safety, Beijing, China
| | - Zhanhui Wang
- National Key Laboratory of Veterinary Public Health safety, College of Veterinary Medicine China Agricultural University, Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, and Beijing Laboratory for Food Quality and Safety, Beijing, China
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Chang X, Cheng Y, Wang X, Wang Y, Liu X, Han T, Gao Z, Zhou H. A novel ultrasensitive and fast aptamer biosensor of SEB based on AuNPs-assisted metal-enhanced fluorescence. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:159977. [PMID: 36347282 DOI: 10.1016/j.scitotenv.2022.159977] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 11/01/2022] [Accepted: 11/01/2022] [Indexed: 06/16/2023]
Abstract
A fluorescent biosensor strategy was developed in combination with immunomagnetic separation for rapid and sensitive detection of staphylococcal enterotoxin B (SEB). Magnetic nanoparticles (MNPs) modified with aptamer of SEB could capture the SEB. Then the gold nanoparticles (AuNPs) fluorescent probe was added and a "sandwich structure" was formed between AuNPs, SEB and MNPs. The MNPs-SEB-AuNPs structure could be separated with an additional magnetic field, which resulted the lower signals of AuNPs fluorescent probe. In optimal conditions, the current method displayed a broad quantitative range from 100 to 107 fg/mL and the limit of detection was 3.43 fg/mL. The recovery of SEB-spiked milk samples ranged from 92.00 to 119.00 %, which revealed that the developed method had great accuracy. Furthermore, the method was fast and economical for ultrasensitive detection. Therefore, the fluorescent biosensor based on MNPs-AuNPs is promising for the detection of other environmental and food pollutants.
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Affiliation(s)
- Xueyu Chang
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, People's Republic of China
| | - Yaqian Cheng
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, People's Republic of China
| | - Xinke Wang
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, People's Republic of China
| | - Yonghui Wang
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, People's Republic of China
| | - Xueli Liu
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, People's Republic of China
| | - Tie Han
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, People's Republic of China
| | - Zhixian Gao
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, People's Republic of China.
| | - Huanying Zhou
- Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, People's Republic of China.
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Multifunctional 3D electrode platform for real-time in situ monitoring and stimulation of cardiac tissues. Biosens Bioelectron 2018; 112:149-155. [DOI: 10.1016/j.bios.2018.04.037] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 04/09/2018] [Accepted: 04/17/2018] [Indexed: 12/26/2022]
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Mondal B, N B, Ramlal S, Kingston J. Colorimetric DNAzyme Biosensor for Convenience Detection of Enterotoxin B Harboring Staphylococcus aureus from Food Samples. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:1516-1522. [PMID: 29350529 DOI: 10.1021/acs.jafc.7b04820] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In the present study, a colorimetric DNAzymes biosensor strategy was devised in combination with immunomagnetic separation for rapid and easy detection of enterotoxin B harboring Staphylococcus aureus from food and clinical samples. The method employs immunocapture of S. aureus and amplification of seb gene by DNAzyme complementary sequence integrated forward primer and with specific reverse primer. The DNAzyme sequence integrated dsDNA PCR products when treated with hemin and TMB (3,3',5,5'-tetramethylbenzidine) in the presence of H2O2 produce colorimetric signal. A linear relationship of optical signal with the initial template of seb was obtained which could be monitored by visually or spectrophotrometrically for qualitative and quantitative detection. The limit of detection for the assay was approximately 102 CFU/mL of seb gene harboring target. This method is convenient compared to gel based and ELISA systems. Further, spiking studies and analysis on natural samples emphasized the robustness and applicability of developed method. Altogether, the established assay could be a reliable alternative, low-cost, viable detection tool for the routine investigation of seb from food and clinical sources.
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Affiliation(s)
- Bhairab Mondal
- Defence Food Research Laboratory , Microbiology Division, Siddarthanagar, Mysore, Karnataka 570011, India
| | - Bhavanashri N
- Defence Food Research Laboratory , Microbiology Division, Siddarthanagar, Mysore, Karnataka 570011, India
| | - Shylaja Ramlal
- Defence Food Research Laboratory , Microbiology Division, Siddarthanagar, Mysore, Karnataka 570011, India
| | - Joseph Kingston
- Defence Food Research Laboratory , Microbiology Division, Siddarthanagar, Mysore, Karnataka 570011, India
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Mondal B, Ramlal S, Lavu PS, N B, Kingston J. Highly Sensitive Colorimetric Biosensor for Staphylococcal Enterotoxin B by a Label-Free Aptamer and Gold Nanoparticles. Front Microbiol 2018; 9:179. [PMID: 29487580 PMCID: PMC5816949 DOI: 10.3389/fmicb.2018.00179] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 01/25/2018] [Indexed: 11/20/2022] Open
Abstract
A simple, sensitive and selective colorimetric biosensor for the detection of Staphylococcal enterotoxin B (SEB) was developed using SEB-binding aptamer (SEB2) as recognition element and unmodified gold nanoparticles (AuNPs) as colorimetric probes. The assay is based on color change from red to purple due to conformational change of aptamer in the presence of SEB, and the phenomenon of salt-induced AuNPs aggregation which could be monitored by naked eye or UV–vis spectrometer. Results showed that the AuNPs can effectively differentiate the SEB induced conformational change of the aptamer in the presence of a given high salt concentration. A linear response in the range of 50 μg/mL to 0.5 ng/mL of SEB concentration was obtained. The assay was highly specific to SEB as compared to other related toxins. The limit of detection (LOD) of SEB achieved within few minutes was 50 ng/mL visually and spectrometric method improved it to 0.5 ng/mL. Robustness of the assay was tested in artificially spiked milk samples and cross-checked using in house developed sandwich ELISA (IgY as capturing and SEB specific monoclonal as revealing antibody) and PCR. This colorimetric assay could be a suitable alternative over existing methods during biological emergencies due to its simplicity, sensitive and cost effectiveness.
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Affiliation(s)
- Bhairab Mondal
- Microbiology Division, Defence Food Research Laboratory, Mysore, India
| | - Shylaja Ramlal
- Microbiology Division, Defence Food Research Laboratory, Mysore, India
| | - Padma S Lavu
- Microbiology Division, Defence Food Research Laboratory, Mysore, India
| | - Bhavanashri N
- Microbiology Division, Defence Food Research Laboratory, Mysore, India
| | - Joseph Kingston
- Microbiology Division, Defence Food Research Laboratory, Mysore, India
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Adzhri R, Md Arshad M, Gopinath SC, Ruslinda A, Fathil M, Ayub R, Nor MNM, Voon C. High-performance integrated field-effect transistor-based sensors. Anal Chim Acta 2016; 917:1-18. [DOI: 10.1016/j.aca.2016.02.042] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 02/24/2016] [Accepted: 02/25/2016] [Indexed: 12/18/2022]
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Wang Y, Salazar JK. Culture-Independent Rapid Detection Methods for Bacterial Pathogens and Toxins in Food Matrices. Compr Rev Food Sci Food Saf 2015; 15:183-205. [DOI: 10.1111/1541-4337.12175] [Citation(s) in RCA: 161] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 09/14/2015] [Indexed: 11/29/2022]
Affiliation(s)
- Yun Wang
- Div. of Food Processing Science and Technology; U.S. Food and Drug Administration; Bedford Park IL U.S.A
| | - Joelle K. Salazar
- Div. of Food Processing Science and Technology; U.S. Food and Drug Administration; Bedford Park IL U.S.A
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Zhang Z, Yu L, Xu L, Hu X, Li P, Zhang Q, Ding X, Feng X. Biotoxin sensing in food and environment via microchip. Electrophoresis 2014; 35:1547-59. [DOI: 10.1002/elps.201300570] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 02/21/2014] [Accepted: 03/20/2014] [Indexed: 12/23/2022]
Affiliation(s)
- Zhaowei Zhang
- Oil Crops Research Institute; Chinese Academy of Agricultural Sciences; Wuhan China
- Key Laboratory of Biology and Genetic Improvement of Oil Crops; Ministry of Agriculture; Wuhan China
| | - Li Yu
- Oil Crops Research Institute; Chinese Academy of Agricultural Sciences; Wuhan China
- Laboratory of Risk Assessment for Oilseeds Products (Wuhan); Ministry of Agriculture; Wuhan China
| | - Lin Xu
- Oil Crops Research Institute; Chinese Academy of Agricultural Sciences; Wuhan China
- Quality Inspection and Test Center for Oilseeds Products; Ministry of Agriculture; Wuhan China
| | - Xiaofeng Hu
- Oil Crops Research Institute; Chinese Academy of Agricultural Sciences; Wuhan China
- Key Laboratory of Detection for Mycotoxins; Ministry of Agriculture; Wuhan China
| | - Peiwu Li
- Oil Crops Research Institute; Chinese Academy of Agricultural Sciences; Wuhan China
- Key Laboratory of Biology and Genetic Improvement of Oil Crops; Ministry of Agriculture; Wuhan China
- Laboratory of Risk Assessment for Oilseeds Products (Wuhan); Ministry of Agriculture; Wuhan China
- Quality Inspection and Test Center for Oilseeds Products; Ministry of Agriculture; Wuhan China
- Key Laboratory of Detection for Mycotoxins; Ministry of Agriculture; Wuhan China
| | - Qi Zhang
- Oil Crops Research Institute; Chinese Academy of Agricultural Sciences; Wuhan China
- Key Laboratory of Biology and Genetic Improvement of Oil Crops; Ministry of Agriculture; Wuhan China
| | - Xiaoxia Ding
- Key Laboratory of Biology and Genetic Improvement of Oil Crops; Ministry of Agriculture; Wuhan China
- Laboratory of Risk Assessment for Oilseeds Products (Wuhan); Ministry of Agriculture; Wuhan China
| | - Xiaojun Feng
- Britton Chance Center for Biomedical Photonics at Wuhan National Laboratory for Optoelectronics-Hubei Bioinformatics and Molecular Imaging Key Laboratory; Systems Biology Theme, Department of Biomedical Engineering, College of Life Science and Technology; Huazhong University of Science and Technology; Wuhan China
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Bruck HA, Yang M, Kostov Y, Rasooly A. Electrical percolation based biosensors. Methods 2013; 63:282-9. [PMID: 24041756 PMCID: PMC3902888 DOI: 10.1016/j.ymeth.2013.08.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 07/30/2013] [Accepted: 08/28/2013] [Indexed: 01/29/2023] Open
Abstract
A new approach to label free biosensing has been developed based on the principle of "electrical percolation". In electrical percolation, long-range electrical connectivity is formed in randomly oriented and distributed systems of discrete elements. By applying this principle to biological interactions, it is possible to measure biological components both directly and electronically. The main element for electrical percolation biosensor is the biological semiconductor (BSC) which is a multi-layer 3-D carbon nanotube-antibody network. In the BSC, molecular interactions, such as binding of antigens to the antibodies, disrupt the network continuity causing increased resistance of the network. BSCs can be fabricated by immobilizing conducting elements, such as pre-functionalized single-walled carbon nanotubes (SWNTs)-antibody complex, directly onto a substrate, such as a Poly(methyl methacrylate) (PMMA) surface (also known as plexi-glass or Acrylic). BSCs have been demonstrated for direct (label-free) electronic measurements of antibody-antigen binding using SWNTs. If the concentration of the SWNT network is slightly above the electrical percolation threshold, then binding of a specific antigen to the pre-functionalized SWNT dramatically increases the electrical resistance due to changes in the tunneling between the SWNTs. Using anti-staphylococcal enterotoxin B (SEB) IgG as a "gate" and SEB as an "actuator", it was demonstrated that the BSC was able to detect SEB at concentrations of 1 ng/ml. Based on this concept, an automated configuration for BSCs is described here that enables real time continuous detection. The new BSC configuration may permit assembly of multiple sensors on the same chip to create "biological central processing units (CPUs)" with multiple biological elements, capable of processing and sorting out information on multiple analytes simultaneously.
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Affiliation(s)
- Hugh Alan Bruck
- University of Maryland College Park (UMCP), College Park MD 20742
| | - Minghui Yang
- College of Chemistry and Chemical Engineering, Central South University, Changsha, China, 410083, China
| | | | - Avraham Rasooly
- Division of Biology, Office of Science and Engineering, FDA, Silver Spring, MD 20993
- National Cancer Institute, Rockville, MD 20850
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McGrath TF, Elliott CT, Fodey TL. Biosensors for the analysis of microbiological and chemical contaminants in food. Anal Bioanal Chem 2012; 403:75-92. [PMID: 22278073 DOI: 10.1007/s00216-011-5685-9] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Revised: 11/17/2011] [Accepted: 12/19/2011] [Indexed: 10/14/2022]
Abstract
Increases in food production and the ever-present threat of food contamination from microbiological and chemical sources have led the food industry and regulators to pursue rapid, inexpensive methods of analysis to safeguard the health and safety of the consumer. Although sophisticated techniques such as chromatography and spectrometry provide more accurate and conclusive results, screening tests allow a much higher throughput of samples at a lower cost and with less operator training, so larger numbers of samples can be analysed. Biosensors combine a biological recognition element (enzyme, antibody, receptor) with a transducer to produce a measurable signal proportional to the extent of interaction between the recognition element and the analyte. The different uses of the biosensing instrumentation available today are extremely varied, with food analysis as an emerging and growing application. The advantages offered by biosensors over other screening methods such as radioimmunoassay, enzyme-linked immunosorbent assay, fluorescence immunoassay and luminescence immunoassay, with respect to food analysis, include automation, improved reproducibility, speed of analysis and real-time analysis. This article will provide a brief footing in history before reviewing the latest developments in biosensor applications for analysis of food contaminants (January 2007 to December 2010), focusing on the detection of pathogens, toxins, pesticides and veterinary drug residues by biosensors, with emphasis on articles showing data in food matrices. The main areas of development common to these groups of contaminants include multiplexing, the ability to simultaneously analyse a sample for more than one contaminant and portability. Biosensors currently have an important role in food safety; further advances in the technology, reagents and sample handling will surely reinforce this position.
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Affiliation(s)
- T F McGrath
- ASSET Technology Centre, Institute of Agri-Food and Land Use, School of Biological Sciences, Queen's University Belfast, Belfast, UK.
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Piezoelectric immunosensor for direct and rapid detection of staphylococcal enterotoxin A (SEA) at the ng level. Biosens Bioelectron 2011; 29:140-4. [DOI: 10.1016/j.bios.2011.08.007] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Revised: 08/02/2011] [Accepted: 08/03/2011] [Indexed: 11/20/2022]
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Computerized disease profiling using GPS-linked multi-function sensor cartridges. J Med Syst 2011; 36:2537-45. [PMID: 21667099 DOI: 10.1007/s10916-011-9726-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2011] [Accepted: 04/25/2011] [Indexed: 10/18/2022]
Abstract
Disease identification in public health monitoring routinely employs analyte detection systems capable of discriminating mixtures of analytes, toxins, cells and/or bacteria in medical and/or environmental solutions. The development of smart sensors capable of discriminating such compounds has become increasingly important for clinical, environmental, and health applications. While some sensors have been fashioned for single analyte detection, methods and systems that facilitate rapid screening of multiple clinical components are needed, serving as triggers for potential epidemics or more specific confirmatory testing. In public health applications, there is like need for immediate collection of geocoded data tagged by disease identification characteristics, with corresponding alerting capabilities. In this technology review we propose one promising model for using a combination of emerging systems-based technologies in multi sensor cartridges, integrated with GPS-enabled, alert-capable mobile phone devices.
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Yang M, Sun S, Bruck HA, Kostov Y, Rasooly A. Lab-on-a-chip for label free biological semiconductor analysis of staphylococcal enterotoxin B. LAB ON A CHIP 2010; 10:2534-2540. [PMID: 20668726 DOI: 10.1039/c005141a] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We describe a new lab-on-a-chip (LOC) which utilizes a biological semiconductor (BSC) transducer for label free analysis of Staphylococcal Enterotoxin B (SEB) (or other biological interactions) directly and electronically. BSCs are new transducers based on electrical percolation through a multi-layer carbon nanotube-antibody network. In BSCs the passage of current through the conductive network is dependent upon the continuity of the network. Molecular interactions within the network, such as binding of antigens to the antibodies, disrupt the network continuity causing increased resistance of the network. For the fabrication of a BSC based detector, we combined several elements: (1) BSC transducers for direct detection, (2) LOC for flow through continuous measurements, (3) a digital multimeter with computer connection for data logging, (4) pumps and valves for fluid delivery, and (5) a computer for fluid delivery control and data analysis. Polymer lamination technology was used for the fabrication of a four layer LOC for BSC detection, the BSC on the chip is fabricated by immobilizing pre-functionalized single-walled carbon nanotubes (SWNTs)-antibody complex directly on the PMMA surface of the LOC. SEB samples were loaded into the device using a peristaltic pump and the change in resistance resulting from antibody-antigen interactions was continuously monitored and recorded. Binding of SEB rapidly increases the BSC electrical resistance. SEB in buffer was assayed with limit of detection (LOD) of 5 ng mL(-1) at a signal to baseline (S/B) ratio of 2. A secondary antibody was used to verify the presence of the SEB captured on the surface of the BSC and for signal amplification. The new LOC system permits rapid detection and semi-automated operation of BSCs. Such an approach may enable the development of multiple biological elements "Biological Central Processing Units (CPUs)" for parallel processing and sorting out automatically information on multiple analytes simultaneously. Such an approach has potential use for point-of-care medical and environmental testing.
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Affiliation(s)
- Minghui Yang
- Center for Advanced Sensor Technology, University of Maryland Baltimore County, MD 21250, USA
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