High-resolution liquid chromatographic analysis of methylated purine and pyrimidine bases in transfer RNA

Methylated and major purine and pyrimidine bases were separated and quantified by high-resolution liquid chromatography after hydrolyzing transfer ribonucleic acids (tRNAs). Separation was accomplished by eluting the hydrolyzed samples from an anion-exchange column with a concentration gradient of ammonium acetate at pH 9.2. Isolated sample of tRNA were hydrolyzed to the free bases with a trifluoroacetic acid-formic acid mixture of 200 degrees. Detection limits of 100-200 ng/ml were measured for the methylated bases; analytical data are reported for ten methylated bases plus the four major bases of calf liver and rat liver tRNA.