Ion concentration polarization (ICP)-based lateral-flow chromatographic strip for immunodetection

Abstract

The invention provides an ICP-based lateral-flow chromatographic strip for immunodetection. The ICP-based lateral-flow chromatographic strip comprises a Nafion permselective membrane, a label pad, a test line, a control line and water-absorbing pads. In detection, the water-absorbing pads located at the two ends of the strip are wetted; then a to-be-detected sample is added to a sample introduction point on the strip; and a negative electrode is applied to the upper stream of the Nafion permselective membrane of the strip, and a positive electrode is applied to the other end of the strip. Under the action of an electric field, the to-be-detected sample moves towards the positive electrode and gathers due to ICP effect and is eventually captured by the test line. After completion of energization, a dry water-absorbing pad is allowed to contact with the part, located at the lower stream of the control line, of the strip, and the label pad is allowed to contact with the strip at the same time; a buffer solution is used for flushing the label pad; under chromatographic action, a labeled substance is separately bonded with the sample on the test line and with the control line; and thus, immunodetection is accomplished. According to the invention, the to-be-detected sample on the strip is enriched and directionally driven via the ICP effect under the action of the electric field and are captured by the test line, so detection sensitivity is improved.

Description

technical field [0001] The invention relates to the field of life science and medical detection, in particular to an ion concentration polarization effect (Ion Concentration Polarization, ICP) immunodetection lateral flow chromatography paper strip. Background technique [0002] The immunoassay method is based on the principle of specific binding between antigens and antibodies to perform qualitative or quantitative detection of the samples to be tested. Immunochromatographic detection based on lateral flow paper strips has always played an important role in the initial screening and rapid diagnosis of diseases due to its simple detection method, low detection cost, and short detection time. However, due to the limitations of the detection principle itself, the sensitivity of lateral flow paper strip immunochromatographic detection is relatively low, and it is difficult to achieve accurate quantitative detection. [0003] The traditional lateral flow paper strip relies on t...

AI Technical Summary

Problems solved by technology

However, due to the limitations of the detection principle itself, the sensitivity of lateral flow paper strip immunochromatographic detection is relatively low, and it is difficult to achieve accurate quantitative detection

[0003] The traditional lateral flow paper strip relies on the capillary chromatography force provided by the nitrocellulose membrane to realize the directional movement of the test sample, and realizes the capture and detection of the test sample through the test line. During the chromatographic flow process on the test line, part of the sample to be tested will inevitably remain in the paper strip area upstream of the test line, thus reducing the detection sensitivity

In addition, due to the difference in the consistency of nitrocellulose membranes between different paper strips, under the action of single capillary chromatography, even with the same concentration of samples to be tested, there will be differences in the capture results on the test line. Therefore, the traditional side Difficult to achieve quantitative detection of flow paper strips

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