an electrical biosensor for analyte determination is prepared by polymerization of a mixture of a biological receptor capable of binding an analyte in a sample , a protein and a polymerizing agent such as glutaraldehyde to form a polymeric film on a transducer . the mixture preferably contains a stabilizer selected from lipids , detergents and antioxidents . the receptor may be an acetylcholine receptor and the analyte , acetylcholine . a preferred stabilizer is a combination of phosphatidyl choline and octyphenoxypolyethoxyethanol . in carrying out a determination , analyte in a sample binds to the receptor causing a change in an electrical characteristic of the film which is indicative of the presence of the analyte . the biosensor may contain a second polymeric film that is free of the receptor and which serves as a control .