Flow-Injection Amperometric Determination of Tacrine based on Ion Transfer across a Water–Plasticized Polymeric Membrane Interface

A flow-injection pulse amperometric method for determining tacrine, based on ion transfer across a plasticized poly(vinyl chloride) (PVC) membrane, was developed. A four-electrode potentiostat with ohmic drop compensation was used, while a flow-through cell incorporated the four electrodes and the membrane, which contained tetrabutylammonium tetraphenylborate. The influence of the applied potential and of the flow-injection variables on the determination of tacrine was studied. In the selected conditions, a linear relationship between peak height and tacrine concentration was found up to 4×10(-5)M tacrine. The detection limit was 1×10(-7)M. Good repeatability was obtained. Some common ions and pharmaceutical excipients did not interfere.