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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http://dx.doi.org/10.3389/fmicb.2018.00179 | DOI Listing |
Typical biosensing platforms are based on the "lock-and-key" approach, providing high specificity and sensitivity for environmental and food safety monitoring. However, they are limited in their ability to detect multiple analytes simultaneously. With the use of pattern identification methods, biosensor arrays can detect faint fluctuations caused by multiple analytes with similar properties in complex systems.
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State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Engineering Research Center of Technical Textiles, Ministry of Education, College of Materials Science and Engineering, College of Science in Donghua University, State Key Laboratory of Polyolefins and Catalysis, Shanghai Key Laboratory of Catalysis Technology for Polyolefins (Shanghai Research Institute of Chemical Industry Co., Ltd., Shanghai), Key Laboratory of High Performance Fibers & Products, PR China. Electronic address:
Here, a green poly(ionic liquid)-regulated one-pot method is developed for the synthesis of Au@Pt core-shell nanospheres (PNSs) under mild reaction conditions in water. It is found that the poly(ionic liquid) poly[1-methyl-3-butyl (3-hydroxy) imidazole] chloride (PIL-Cl) is very vital to guide the construction of Au@Pt PNSs. The as-obtained Au@Pt-1 PNSs have perfect spherical outlines, porous core-shell structures and large specific surface area by which they exhibit excellent peroxidase-like activity in acidic media and can be used to develop a simple and reliable colorimetric sensing platform.
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January 2025
College of Chemistry and Chemical Engineering, Xinyang Key Laboratory of Functional Nanomaterials for Bioanalysis, Xinyang Normal University, Xinyang 464000, China.
To advance the biological understanding of heat shock protein (HSP) in different types of cancers, it is crucial to achieve its accurate determination. Herein, a dual-mode self-powered photoelectrochemical (PEC) and colorimetric platform was proposed by integrating enzymatic catalysis and a chemical redox cycling amplification strategy. In this system, ascorbic acid (AA), as the signal reporter for PEC and colorimetric assay, can be regenerated during the tris(2-carboxyethyl) phosphine-mediated chemical redox cycling process.
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State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, 214122, China.
A dual-signal aptamer-based assay utilizing colorimetric and fluorescence techniques was developed for the determination of zearalenone (ZEN). The CdTe quantum dots, serving as the fluorescent signal source, were surface-modified onto FeO@SiO and subsequently functionalized with the aptamer. The COF-Au was modified with complementary chain, which possessed peroxide (POD)-like enzyme properties, and could catalyze the peroxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to ox TMB, resulting in the generation of colorimetric signals.
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December 2024
Prokhorov General Physics Institute of the Russian Academy of Sciences, 38 Vavilov Street, 119991 Moscow, Russia.
A novel approach to developing lateral flow assays (LFAs) for the detection of CYFRA 21-1 (cytokeratin 19 fragment, a molecular biomarker for epithelial-origin cancers) is proposed. Magnetic bioconjugates (MBCs) were employed in combination with advanced optical and magnetic tools to optimize assay conditions. The approach integrates such techniques as label-free spectral-phase interferometry, colorimetric detection, and ultrasensitive magnetometry using the magnetic particle quantification (MPQ) technique.
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