Research On Piezoelectric Immunosensor System

Piezoimmunosensor can provide properties of high specificity, sensitivity, rapid response, minitype and simplicity. It becomes a kind of automatic analytical sensors which utilizes the mass-sensing characteristics of the piezoelectric material connected to the biological immunosensing element.This paper describes that a quartz crystal is used to produce bulk wave oscillating in the thickness-shear mode, utilizing the dual-channel to detect the change of micro-mass from the frequency shift.This paper consists of four parts: First, the features and principle of the piezoelectric immunosensor system are described and analyzed. A physical description of various types of acoustic waves is given and prototype sensing element geometries are presented .The acoustic waves include the bulk acoustic wave (BAW), the surface acoustic wave (SAW), Bleustein-Gulyaev (B-G) wave, the love mode and the acoustic plate mode (APM). Through study of the detecting sensitivity and stability of frequency, we analyze and discuss the advantages and disadvantages for various types of vibration modes. The Love mode is the best vibration mode. Second, we design dual-channel piezoelectric ceramics sensing system in experiments in conjunction with electrolytic determination of silver in solution to demonstrate the mass-sensitive theory, analyzing the conditions of the measurements and the sensitivity of the experiments. Third, we design the various of the immunosensors for different vibration modes. Last, we study and discuss the problems of the sensing system. Practical mass-sensitive piezoelectric immunosensor system can be implemented by using devices with higher frequencies of operation or by selecting the sensitive wave vibration mode or by improving techniques for the immobilization of antibody. This type of the sensing system has a good foreground with high performance.