Preparation of colorimetric and fluorescent double-signal nanospheres and application of colorimetric and fluorescent double-signal nanospheres to immunochromatographic quantitative detection

Abstract

The invention discloses preparation of colorimetric and fluorescent double-signal nanospheres and application of the colorimetric and fluorescent double-signal nanospheres to immunochromatographic quantitative detection, and belongs to the field of medical detection. The preparation comprises the following steps: taking nanospheres as main bodies; embedding fluorescent quantum dots into the nanospheres or assembling the fluorescent quantum dots on surfaces of the nanospheres through an ultrasonic swelling method or an assembling method, so as to construct fluorescent nanospheres with rich carboxyl on surfaces and the grain diameter of 100nm to 500nm; assembling nano-gold on the surfaces of the fluorescent nanospheres through the assembling method, so as to obtain the colorimetric and fluorescent double-signal nanospheres. Visual qualitative and fluorescent quantitative detection of a target object can be simultaneously realized by combining the colorimetric and fluorescent double-signal nanospheres with an immunochromatographic technology. The double-signal nanospheres have fluorescent signal and colorimetric signal amplification effects. An immunochromatographic method, which takes the double-signal nanospheres as markers, is simple, convenient and rapid to use; compared with a traditional colloid gold immunochromatographic test paper strip, the colorimetric and fluorescent double-signal nanospheres has the advantages of high sensitivity, good repeatability, capability of accurately quantifying and the like.

Description

technical field [0001] The invention relates to the field of medical testing, in particular to the preparation of a colorimetric fluorescent double-signal nanosphere and its application in immunochromatographic quantitative detection. Background technique [0002] Immunochromatographic rapid detection has attracted widespread attention because of its simplicity and rapidity. Immunochromatography has been widely used in immunoassay, food safety, environmental monitoring and other fields. It usually uses a nitrocellulose membrane as a chromatographic membrane, and the sample solution flows on the chromatographic membrane under capillary action. The target substance in the sample will interact with the receptor (antibody or antigen) to produce a specific immune response. The traditional immunochromatography method uses colloidal gold as a marker, which can accumulate nano-gold in the detection area to develop color, and perform qualitative or semi-quantitative detection by ju...

AI Technical Summary

Problems solved by technology

However, detection based on fluorescent signals requires ultraviolet light excitation, which is very inconvenient for areas with poor medical conditions or for home use, so the scope of application is largely limited.

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