Potentiometric determination of cephalothin

The composition of a pseudo-liquid potential-determining phase for the cephalothin-selective electrode has been determined and the following basic electrode parameters were examined: measurement range, slope, limit of detection, selectivity and lifetime. This paper discusses the effect of side-chain substituents on the electrode properties, the electrode having been used for cephalothin determination in the range 43-436.5 mg l-1 (standard deviation, 0.64-4.5 mg l-1).