Immunochromatographic test strip, and making method and detection method thereof

Abstract

The invention provides an immunochromatographic test strip. The test strip comprises a sample pad, a binding pad, a cellulose nitrate membrane, an absorbent pad and a backing pad, the cellulose nitrate membrane comprises a detection line and a quality control line, and the cellulose nitrate membrane also comprises a double antibody line. The double antibody line is arranged between the detection line and the quality control line. The invention also provides a making method and a detection method of the immunochromatographic test strip. The immunochromatographic test strip reserves the advantages of simple operation, simple structure and low cost of traditional immunochromatographic test strips, effectively avoids the false negative phenomenon appearing in the detection of high concentration of a substance to be tested of traditional test strips, effectively improves the detection accuracy of immunochromatography, and enlarges the linear detection range; and the test strip comprehensively utilizes the signal intensities of the above lines in a display area and the relationship among the signal intensities of the three lines not limited to the signal intensity of the detection line, so the test strip can be used to accurately determine the concentration of the substance to be tested, and the sensitivity and the specificity of immunochromatographic detection are greatly improved.

Description

technical field [0001] The invention relates to an immunochromatography detection technology, in particular to an immunochromatography test strip with an added judgment line, a manufacturing method and a detection method thereof. Background technique [0002] Immunochromatography technology is a new type of detection technology that combines immunolabeling technology and chromatography technology. It can use the chromogenic properties of markers to achieve qualitative, semi-quantitative, and quantitative analysis of the analyte. It uses the microporous filter membrane as the solid phase carrier, the liquid to be tested as the mobile phase, and uses the capillary action and siphon effect of the microporous filter membrane to guide the liquid to be tested to flow forward. The antigen or antibody on the filter membrane reacts to form an immune complex, which stays on the detection line. Through the optical density analysis of the color depth or fluorescence of the marker, the i...

AI Technical Summary

Problems solved by technology

Because the contact time between the analyte and the labeled antigen or antibody is short, there must be insufficient antigen-antibody reaction, then there will be uncaptured analyte and the formed immune complex to siphon together to develop color area, and the immune complex has a larger steric hindrance than the free analyte, and its flow velocity lags behind the free analyte, so there will be uncaptured analytes arriving on the detection line before the immune complex, It reacts with the antigen or antibody immobilized on the display area, occupying the site that should theoretically bind to the immune complex, resulting in a decrease in the immune complex remaining on the detection line, and the signal intensity on the detection line will be weaker than the theoretical one, so prone to false negative results

[0016] 2. In the current interpretation methods of test strip results, as long as the quality control line is colored, whether it is visual observation or instrument reading results, most of them only observe the signal strength on the detection line, and the result judgment basis is single, which is prone to errors

[0017] Since the traditional immunochromatographic test strips based on gold nanoparticles are directly observed by the naked eye, the sensitivity is limited. Other methods, such as enzymatic method, silver staining enhancement method, chemiluminescence method or fluorescence method, some require fluorescence excitation to produce chemiluminescence. , with testing equipment for inspection, the operation is complicated and the cost is high

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