Multi-channel planar waveguide evanescent wave biosensor

Abstract

The invention provides a multi-channel planar waveguide evanescent wave biosensor, belongs to the technical field of biological testing, and particularly relates to fluorescent dye-labeled biological substance luminescence excited by laser, thereby achieving the biological detection technology. The biosensor is characterized in that: in the process of laser optical waveguide in a flat glass medium, a plurality of total reflection points are formed on the interface of two-phase medium, fluorescent labeled biological molecules in the point spatial range are excited by evanescent waves generated at the total reflection points to generate fluorescence, the fluorescence is collected by multimode fibers, and fluorescence signals are detected by a lock-in amplifier. As the laser in planar waveguide process can form a plurality of total reflection points, each total reflection point is marked with different biological molecules and the fluorescence signal is detected separately, simultaneous determination of multi-index in a sample can be achieved. The biosensor has the characteristics of simple waveguide structure, high fluorescence collection efficiency, small background noise interference, enabling simultaneous determination of multi-index and the like.

Description

technical field [0001] The invention designs a planar waveguide evanescent wave biosensor based on the principle of total internal reflection fluorescence, and its application fields include biomedicine, environmental monitoring, food inspection and the like. It can detect a variety of target substances such as biological macromolecules, small organic molecules, viruses and bacteria. Background technique [0002] When the light wave is transmitted in the glass medium by total internal reflection, an evanescent wave can be generated on the side of the optically sparse medium at the total reflection point. The evanescent wave is a kind of energy wave, and its transmission depth is usually only tens to hundreds Nano. In the space where the evanescent wave exists, the biological substances labeled with fluorescent molecules connected to the surface of the chip by adsorption or bioaffinity reaction are excited and generate fluorescence. The fluorescence intensity has a quantitat...

AI Technical Summary

Problems solved by technology

The disadvantages of this technology are: 1) The lens is used to collect fluorescence and occupies a large space, so the system can only accommodate one collection optical path. When measuring the fluorescence intensity of 4 sample cells, a stepping motor is required to move the sample cells together with the sensing elements sequentially Go to the next measurement position, so the biological reaction results of 4 sample pools cannot be measured at the same time, and the measurement period is too long

2) The system contains 4 parallel sample pools, and each sample pool needs to be injected separately. The sampling flow path and procedures are complicated, and the simultaneous determination of multiple indicators in the same sample cannot be realized.

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