The interaction of VO2+ with mono-, di- and trinucleotides and with some of the related nucleosides and bases, was investigated spectrophotom etrically at pH = 4.9. The results point to a preferential interaction of the cation with the phosphate groups of all the nucleotides whereas no interaction with the nucleosides and bases was detected. The vanadyl coordination sphere shows some distortive effects in the case of mononucleotides whereas it appears more regular in the case of di- and trinucleotides. At high pH-values the cation interacts with the deprotonated OH-groups of the ribose moieties. This type of interaction was confirmed by direct measurements with pure ribose and ribose-5'-phosphate, and it was absent in the case of thymidine nucleotides, in which ribose is replaced by 2'-deoxyribose.Publicado on line en 2014.Facultad de Ciencias Exactas