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.