Biological Acoustic Sensors for Microbial Cell Detection

Abstract

One of the most popular areas in microbiology is the development of fast and sensitive methods for the detection of bacteria based on electrophysical analysis. The paper demonstrated the capabilities of various electroacoustic biological sensors for detection and identification of microbial cells. These sensors are based on the following main elements: the piezoelectric resonator with a longitudinal electric field, the piezoelectric resonator with a lateral electric field, the acoustic delay line with inhomogeneous piezoactive acoustic waves, and the delay line using a slot acoustic mode. They can conduct cell detection and identification of bacteria using immobilized microorganisms or directly in cell suspension. The principle of operation of such sensors is based on the registration of the interaction of microbial cells with specific antibodies, bacteriophages, and mini-antibodies. The sensitivity range of microbial cell detection is 103–108 cells/ml with the suspension conductivity of 5–50 μS/cm. At that the analysis time varies from 5 min to several hours. The presented possibilities of electroacoustic biological sensors for the detection of bacteria are focused on the clinical use of onsite as a personalized diagnostic device. The possibility of rapid detection of microflora allows timely diagnosis of the disease and timely medical assistance. In general, acoustic biological sensors form a wide class of detection systems and are very promising for use in microbiology, medicine, and veterinary medicine for solving the problems of detection and identification of bacteria.