Liquid chromatographic determination of 2',3'-dideoxyguanosine in human plasma

A rapid assay for 2',3'-dideoxyguanosine (ddG) in human plasma has been developed. The ddG was first extracted from human plasma using solid phase extraction. The extract containing ddG was then assayed with liquid chromatography using an ODS column and a mobile phase of 9% methanol in pH 6.8 phosphate buffer. The overall method had good accuracy (within 2%), linearity (r = 0.9998), sensitivity (LOD = 1.8 ng, S/N = 3) and recovery (greater than 99% for 5-50 micrograms ddG per ml plasma).