Blood chemistry by disposable ISE with the Chempro 500 system

Potentiometric measurements are usually done with multiple determination electrodes. Disposable electrodes were first introduced on the Ektachem systems by Kodak with the concept of differential potentiometric measurement between the specimen and a reference fluid delivered on two parts of a single slide. In the Chempro 500 system a calibrating solution and the specimen are sequentially measured by the same potentiometric system with a classic reference electrode and selective electrodes present on a disposable device in various combinations. This device is connected to a compact analyzer with a microprocessor, a display and a printer. The authors evaluated the analytical performance of the Chempro 500 on whole blood, plasma and serum specimens over a two months period. Results and practicability are discussed and compared to those of reference instruments, according to requirements of decentralized analysis.