Linear sweep voltammetry of 9-beta-D-ribofuranosyluric acid 5 '-monophosphate in aqueous and micellar media

Linear sweep voltammetric behaviour of 9-beta-D-ribofuranosyluric acid T-mo nophosphate (UA-9R-5'-P) has been studied in phosphate buffers of pH 3.0 an d 7.0 at the pyrolytic graphite electrode in aqueous and micellar media. At pH 3.0 in the presence of non-ionic and anionic surfactants, UA-9R-5'-P ex hibited a single well-defined 2e, 2H(+) oxidation peak, whereas in the pres ence of cationic surfactant (CTAB) the oxidation peak I-a showed a tendency to split into two peaks indicating that the 2e, 2H(+) oxidation of UA-9R-5 '-P in peak I-a reaction occurs in two le steps. The effect of cationic sur factant at pH 3.0 is explained on the basis of hydrophobic penetration of c ationic species in cationic micelles. The products of electrode reaction in micellar medium were found as alloxan, urea and ribosyl phosphate at pH 3. 0 and ribose, allantoin and 5-hydroxyhydantoin 5-carboxamide at pH 7.0 and were similar to those observed in aqueous media. (C) 1999 Elsevier Science B.V. All rights reserved.