RESUMO
Adsorption behavior of pure enantiomers and racemic mixtures of nonsteroidal anti-inflammatory drugs (ibuprofen and naproxen) on human serum albumin (HSA) was evaluated. The HSA was immobilized by Sol-Gel technique and this biomaterial was used in a chromatographic system where frontal analysis experiments were performed at pH 7.4 and temperatures of 25°C and 37°C. The association constants for enantiomers of the drugs were determined by linear adjustment for data corrected just for dead volume. In uncorrected data for non-specific retention, an inverse ratio between the number of sites and the value of the association constant was found. The participation of non-specific retention was estimated by non-linear regression and the values of association constants (Kass), which were determined considering this information, are comparable to some values reported by other methods at 37°C: 1.4 x105 and 5.7 x104 for Ibuprofen (IBU) R and S, respectively, and 2.3 x105 and 1.8x105 for naproxen (NX) R and S, respectively.