Biosensors Based on SOI Nanowire Transistors for Biomedicine and Virusology

Abstract

This article contains the results of research on the topical problem of highly sensitive express registration of biological objects using field-effect transistors with the surface open for analyte access, which are made based on silicon-on-insulator (SOI) films. The possibilities of dielectrophoretic effects for controlling the concentration of the analyte in the area of sensory elements are considered on the example of the indication of viruses of nuclear polyhedrosis and vaccinia. It is shown that the use of the dielectrophoresis (DEPh) effect makes it possible to solve (1) the key tasks for creating sensor systems: increasing the detecting ability, as well as exrtacting and verifying the signal from the target particles; and (2) the fundamental task: determining the charge state of the analyte in solutions without modifying the sensors' surface. The problems and prospects of the mass application of nanowire (NW) biosensors, including those with the dielectrophoretic effect, in biotechnology, virology, etc., are discussed.

Analysis of Electric Field Distribution for SOI-FET Sensors with Dielectrophoretic Control

“…At the p-DEP, the particles are localized both on the DEP electrodes and on the sensor surface. Note that these results were experimentally observed at the virus detection by the sensors with DEP control in the study [ 14 ]. Note also that in the case of the p-DEP, the maximum efficiency of control by the bioparticles from the side of the DEP electrodes can be reached at a high V bg voltage.…”

“…The experimental limit of the detection for the nanowire SOI-FET sensors was found to be on the femtomolar level for proteins and DNA [ 3 , 4 , 5 , 6 ]. The dielectrophoretic (DEP) delivery of the bioparticles to the sensor elements is one of the most successful methods to overcome this issue [ 12 , 13 , 14 , 15 ].…”

“…For a targeted delivery of the bioparticles to the sensor elements, devices with embedded electrodes [ 13 , 14 ] or insulating iDEP structures can be used [ 15 ]. In the DEP platforms with embedded electrodes, planar DEP electrodes are typically located near a sensor element.…”

SOI-FET Sensors with Dielectrophoretic Concentration of Viruses and Proteins

“…It means that, in the case of sensors with DEP-controlled viruses, the DEP force acting on viruses does not affect (acts weakly) the concentration of background proteins near the sensor element. However, despite a large number of experimental and theoretical studies on the DEP-manipulation of bioparticles (see reviews [ 13 , 14 , 17 , 18 ]), only a few reports [ 15 , 18 , 19 , 20 , 21 ] are devoted to such a problem as the DEP delivery of an analyte to FET sensors.…”