[Quantitative analysis of a tetraribonucleotide mixture by ultraviolet spectrophotometry].

Using the least squares method we have calculated the proportions of each nucleotide of a mixture of AMP, CMP, GMP and UMP, after measuring the absorbance of the mixture every ten nanometers from 230 to 290 nm at pH 12.7 and 2. The method is very simple and rapid (the calculations are made in less than one minute), does not require a highly sensitive spectrophotometer to obtain reasonably precise results and, in contrast to the other methods of the literature, it can be applied to quantities as little as 50 micrograms of nucleotides.