Acoustic impedance immunosensors are disclosed that are capable of real-time measurement of GABA in a buffer solution. Several embodiments include a bio-specific recognition layer on a quartz crystal surface, where the bio-recognition layer is formed by molecular self-assembly on a gold electrode surface. Various real time measurements can be made by examining the impedance parameters of the quartz crystal on which the bio-specific recognition layer is located as it interacts with GABA. In one embodiment, the invention includes an electrochemical cell that possesses a working electrode. The working electrode including a layer of piezoelectric material, at least one electrode layer fixed to the piezoelectric material and a bio-specific recognition layer formed on the electrode layer and including anti-GABA. In addition, an electrochemical workstation is connected to at least one electrode of the electrochemical cell and an impedance analyzer is connected to the working electrode.
Acoustic immunosensor for detecting neurotransmitter GABA