Echo wall sensor based on sound evanescent field coupling

Abstract

The invention provides an echo wall sensor based on sound evanescent field coupling, relates to an acoustic wave biosensor used for biological detection. The sensor includes a membrane structure, a thin-walled round tube resonant cavity, a support device and an excitation receiving device, wherein the thin-walled round tube resonant cavity is supported by the support device; the distance between the thin-walled round tube resonant cavity in a joint excitation echo wall mode and the membrane structure is adjustable; the axis of the thin-walled round tube resonant cavity is parallel to the upper surface of the membrane structure and vertical to the propagation direction of acoustic waves; and the input end and the output end of the excitation receiving device used for exciting and receiving lamb waves are fixed on the membrane structure. The sensor separates the transmission function and the sensing function, and improves the quality factor of acoustic wave resonance in liquid phase, the label-free biosensors of high sensitivity, low detection-limit detection and in integration and array form can be manufactured, and information in the thin-walled resonant cavity in the echo wall mode and related physical information of a to-be-detected object can be obtained through the variation of detection signals.

Description

technical field [0001] The invention relates to an acoustic wave biosensor for biological detection, in particular a whispering wall sensor based on acoustic evanescent field coupling. Background technique [0002] An ideal biosensor should not only have high sensitivity, but also have the characteristics of small size, portability, reusability, high specificity and stable operation. At present, although the whispering gallery optical sensor has a very high quality factor (Q value) and detection sensitivity in the air, its characteristics in the liquid have yet to be investigated. In addition, in order to achieve the mode matching between the optical fiber and the micro-resonator, it usually uses a tapered optical fiber to couple light into the resonant cavity. At this time, the diameter of the optical fiber is usually small, which is not only difficult to manufacture, but the system is fragile and difficult to reuse. However, thin-film acoustic wave devices can be designed...

AI Technical Summary

Problems solved by technology

Therefore, although its theoretical sensitivity is extremely high, due to the low Q value, the frequency change caused by phase noise often exceeds the frequency change caused by antigen-antibody binding, especially in a liquid environment, it is difficult to detect the tiny mass caused by molecular binding in an affinity reaction change, making its high sensitivity feature unable to play

Images