Estimation of tetrahydrobiopterin and other pterins in cerebrospinal fluid using reversed-phase high-performance liquid chromatography with electrochemical and fluorescence detection.

We describe an isocratic, reversed-phase high-performance liquid chromatographic method for the simultaneous measurement of fully oxidised, dihydro- and tetrahydropterins in cerebrospinal fluid. Tetrahydrobiopterin is detected electrochemically using an ESA Coulochem detector in the redox mode. Dihydropterins are detected by fluorescence following post-column electrochemical oxidation, and fully oxidised pterins by their natural fluorescence. Apart from addition of antioxidants, no sample preparation is required. Comparison is made with methods requiring chemical oxidation for detection of tetrahydrobiopterin. Some results on children with neurological disease are presented.