Direct Determination of Salicylic Acid in Human Serum by Matrix Isopotential Synchronous Fluorescence

A new spectrofluorimetric method has been applied for determining salicylic acid in human serum for concentrations between 0.020 and 0.252 ppm. The method was performed in an aqueous medium at pH 6.0 attained by addition of phosphate buffer solution. The method is based on the use of a new technique called matrix isopotential synchronous fluorescence, which enables us to determine analytes in complex fluorescent matrices without the need for tedious prior separation. The sensitivity and reproducibility achieved in these matrices are better than those achieved with the fluorimetric methods described in the references.