Fluorescence-quenched colloidal gold immunochromatographic test strip, preparation method and application of fluorescence-quenched colloidal gold immunochromatographic test strip

Abstract

The invention provides a fluorescence-quenched colloidal gold chromatography test strip which comprises a bottom plate, and a sample pad, a combination pad, a nitrocellulose membrane and absorbent paper which are sequentially arranged on the bottom plate from left to right; the sample pad and the combination pad, the combination pad and the nitrocellulose membrane, and the nitrocellulose membraneand the absorbent paper are partially laminated; gold nanoparticles are arranged on the combination pad, and antibodies of a to-be-detected object are marked on the gold nanoparticles; an antigen anda detection T line of a dual-excitation dual-emission up-conversion nanoparticle labeled detection object are fixed on the nitrocellulose membrane; the up-conversion nanoparticles can emit red light or green light under the excitation of two different near-infrared lights at the same time. The invention also discloses a preparation method and a detection method of the kit. According to the chromatographic test strip and the detection method thereof provided by the invention, the result can be directly observed under the excitation of near-infrared light, the sensitive components are accuratelyand quantitatively detected, the background interference is eliminated, the background value is low, the signal is stable, and the sensitivity is greatly improved.

Description

technical field [0001] The invention belongs to the technical field of biomedical diagnosis and food safety detection, and specifically relates to a colloidal gold immunochromatographic test strip based on double-excitation and double-emission up-conversion luminescence nanoparticle fluorescence quenching, a preparation method and an application thereof. Background technique [0002] Harmful chemical and biological contaminants in environmental and food samples are a global concern due to their adverse effects on ecosystems. These substances come from residual medical (pharmaceutical pollutants), agricultural (pesticides), biological (pathogens and the toxins they release) and industrial (chemical solvents, industrial by-products, etc.) waste. These substances are highly carcinogenic and harmful to humans. adverse effects on health. Therefore, the timely detection of carcinogens and pathogenic bacteria in food has become a major issue in modern biomedicine. [0003] Immuno...

AI Technical Summary

Problems solved by technology

[0007] The application of existing fluorescent materials in immunochromatography technology has significantly improved the detection performance of the method, but when the existing up-conversion test strips detect carcinogens such as aflatoxin (AFT) by immunochromatography, Because the organic dye markers used are easy to decompose under light, prone to photobleaching, and have the characteristics of concentration quenching, which affects the accuracy and reliability of the analysis results; it is used to label carcinogen antibodies or pathogenic bacteria antibodies. Nanoparticles have only one detection signal and low sensitivity, so the quantitative detection results of the carcinogen content in the sample to be detected are not accurate

At the same time, the preparation and detection methods of immunochromatographic test paper in the prior art cannot support the precise quantitative detection of sensitive components or substances.

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