Quantitation of gold lymphocyte binding during chrysotherapy

Carbon rod atomic absorption analysis (CRA) was applied to the quantiation of gold lymphocyte content (GLC) during chrysotherapy. Sensitivity and accuracy of CRA compared favorably with 195Au isotopic scintillation counting, circumventing the limitations and hazards of the latter in clinical applications. Picogram gold quantification of limited sample volume, less than 10 ml blood, e.g., 10(4)-10(5) lymphocytes (5 microliters) containing 5-10 pg was achieved. GLC after IM administration increased significantly in 60% of patients; for the remainder, GLC was observed to be independent of plasma gold content or cumulative dosage. GLC during auranofin administration (6 mg/day p.o.) approached values for IM gold despite significantly lower plasma levels. Unique sensitivity of CRA enables analysis of GLC under therapeutic conditions that could elucidate whether gold alters functional determinants.