Deoxynucleoside composition of DNAs and modified nucleoside composition of tRNAs determined at nanomole sensitivity by reversed-phase liquid chromatography

Selected purified tRNA and DNA samples were digested by standard enzymatic methods, and the nucleosides were separated by high-pressure liquid chromatography on reversedphase columns. Nanomole sensitivity was obtained by use of an integrator. The nucleosides were detected at wavelengths near their uv-absorption maxima, including 220 nm for dihydrouridine, and 330 nm for 4-thiouridine. Recovery values for the individual nucleosides were in the range of 94–100%. The nucleoside composition of the DNA and tRNA digests were in accurate and precise agreement with published values.