An amperometric glucose electrode based on carbon paste, chemically modified with glucose dehydrogenase, nicotinamide adenine dinucleotide, and a phenoxazine mediator, coated with a poly(ester sulfonic acid) cation exchanger

An amperometric glucose electrode is described based on carbon paste chemically modified with glucose dehydrogenase, nicotinamide adenine dinucleotide, and a mediator, Meldola Blue. The surface of the chemically modified carbon paste electrode (CMCPE) is protected by coverage with a poly(ester sulfonic acid) cation exchanger to form a membrane, which prevents the aqueous soluble species from dissolving out of the CMCPE. The CMCPE was investigated in the flow‐injection analysis operation. Linear calibration curves for glucose were obtained between 100 μM and 20 mM glucose at +100 mV versus Ag/AgCl. The sample throughput was 40 h −1 . The electrodes remained stable for about 2 weeks.