The results suggest that, in the matrixes studied, TAX may be able to exert its biological activities systemically when applied by these routes. Furthermore, it exhibits greater permeability potential when administered by intravaginal route.

The aqueous extract of the bark of Pinus pinaster has a high concentration of polyphenols represented by a mixture of procyanidins, besides taxifolin, phenolic acids, cinnamic acids and their glycosides. Its quality control is specified in the United States Pharmacopeia, and the assay test is performed by determination of the total procyanidins content. However, determining the individual polyphenol content may represent an additional quality parameter for this extract. In this sense, the present study aimed to develop and optimize a method of high performance liquid chromatography with photodiode array detection (HPLC-PDA) for quantification of taxifolin in the bark extract of P. pinaster, using a 3 3 Box-Behnken factorial design. The proposed method was validated for specificity, linearity, limits of detection and quantification, precision, accuracy and robustness and it has shown that taxifolin may be used as a chemical marker for quality control of the bark extract of P. pinaster.