Enzyme sensors based on a coated-wire electrode. Effects of buffer concentration and pH on the potentiometric response of penicillin sensor.

The effects of pH and concentration of working buffer on the potentiometric response of a penicillin sensor based on a carboxyl-substituted poly(vinyl chloride)-coated Ag electrode were examined. The sensor showed a good response in buffer solutions of pH 6.5-8.5. The buffer concentration affected the response of the sensor. Higher concentration buffer (30 mM) strongly disturbed the response due to the higher buffer capacity.