Fast response potentiometric acetylcholine biosensor

A simple, convenient method is proposed for the preparation of fast respons e potentiometric acetylcholine (ACh) biosensors based on pH detection. As s ignal transducer antimony pH electrodes with Bat, easily renewable surface were used. Among different immobilization techniques tested the immobilizat ion of acetylcholinesterase (AChE) onto the antimony disk electrode surface by intermolecular cross linkage of AChE and BSA via glutaraldehyde vapor i n vacuum proved to be the most advantageous with respect to the analytical parameters of the biosensor. The biosensor was tested for the determination of an or::organophosphorus type insecticide; trichlorfon using an indirect approach based on the AChE inhibiting character of this pesticide. After e ach inhibition measurement cycle the biosensor was reactivated in pyridin-2 -aldoxime methiodide for prolonged lifetime. The fast response of the ACh b iosensor resulted in a considerable because of the real analysis rime of th e inhibitor.