Capillary electrophoresis separation of the new anti-AIDS agents 9-(2-phosphonylmethoxyethyl)adenine and 9-(2-phosphonylmethoxyethyl)-2,6-diaminopurine in mixtures with some monoribonucleotides or the most common deoxynucleotides.

The present work describes an electrophoretic method for the separation and determination of the new antivirals, 9-(2-phosphonylmethoxyethyl)adenine (PMEA) and 9-(2-phosphonylmethoxyethyl)-2,9-diaminopurine (PMEDAP) in model mixtures with some monoribonucleotide isomers (3'-AMP, 2'-CMP, 3'-CMP, 3'-GMP, 2'-GMP, 3'-UMP, 5'-GMP, and 5'-UMP) or with the most common deoxynucleotides (dCMP, dCDP, dCTP, dTMP, dTDP, dTTP, dGMP, dGDP, dGTP, dAMP, dADP, dATP). A fused-silica capillary tube, 75 microm ID, 67.8 cm total length (60.3 cm length to the detector), with detection at 210 nm was employed. A hydrodynamic injection for 10 s (1.5 psi vacuum) was utilized to introduce the sample, and 30 kV voltage was applied for the separation. The complete separation of PMEA and PMEDAP from the mononucleotide isomers and deoxynucleotide mixtures is possible in less that 10 min and 25 min, respectively, using 20 mM borate buffer, pH 9.9, with the addition of 10 mM beta-cyclodextrin. Efficiencies of more than 120 000 and resolution higher than 1.9 were reached for each of the compounds studied. This capillary electrophoretic procedure opens the possibility for future determination of PMEA and PMEDAP in cell pool samples.