HPLC determination of neopterin in biological liquids for clinical purposes

A HPLC method is proposed for determining neopterin in biological liquids. The method was realized using a standard chromatographic instrumentation. Neopterin was isolated from blood serum and urine by solid-phase extraction on cartridges containing 30 mg of supercrosslinked polystyrene. The separation was carried out on an Irica chromatograph (Japan) equipped with means of UV (350 nm) and fluorimetric (es350-em430 nm) detection. The degree of extraction was 96–113%, and the sensitivity of UV and fluorimetric detection was 0.1 and ∼0.03 ng, respectively (at signal-to-noise ratio 3). It is shown that the method is suitable for use in routine clinical analysis of neopterin in biological liquids.