ELECTROCHEMICAL DETECTABILITY OF CATECHOLAMINES USING HIGH PERFORMANCE LIQUID CHROMATOGRAPHY AND THERMAL STABILITY OF A STRONGLY ACIDIC CATION EXCHANGE RESIN IN AQUEOUS SOLUTION (HPLC)

The analysis of catecholamines has been investigated using an ion-pairing chromatographic method which utilizes a controlled potential coulometric detector. Two coulometric detectors with different electrolytic cell designs have been investigated. The resulting sensitivity was comparable to that obtained with an amperometric detector. This technique has been applied to the analysis of plasma catecholamines. Cation exchange resin Dowex 50W-X8 has been heated in alkaline water (pH 9.3-9.5) at a temperature of 100(DEGREES)C in order to study its thermal stability. Iron was added to the test system to study its possible catalylic effect on the resin thermal stability. Measurements of changes in capacity were made and the decomposition products formed were investigated. The resin was found to be stable at 100(DEGREES)C. The main water soluble decomposition product released by the resin was sulfate ion. Organic material was also found but it was not possible to identify it. Iron was found to have small or negligible effect on the thermal decomposition of the resin.