SEPARATION OF THE ANOMERS AND ISOMERS OF 2'-DEOXYURIDINE AND THYMIDINE BY CAPILLARY ZONE ELECTROPHORESIS

Anomerisation and isomerisation take place during acidic degradation o f 2'-deoxyuridine (dUrd) and thymidine (Thd) due to the opening and re closure of the furanose ring. A capillary electrophoretic method was d eveloped which was able to separate dUrd and Thd from their respective anomers and pentopyranosyl isomers. Using a fused-silica capillary (7 0 cm x 75 mum I.D.) the influence of the type, pH and concentration of the buffer was systematically investigated as well as the effect of v oltage and temperature. With a 20 mM sodium tetraborate buffer of pH 9 .5 and 10 for dUrd and Thd, respectively, good resolution between anom ers and isomers was obtained at 20 kV and 50-degrees-C.