Pharmaceutica Analytica Acta

Abstract

Simultaneous Determination of Coumarin, O-Coumaric Acid, Dihydrocoumarin and Syringaldehyde in Guaco Extracts and Pharmaceutical Preparations by HPLC-DAD

João Cleverson Gasparetto, Thais Martins Guimarães de Francisco, Francinete Ramos Campos and Roberto Pontarolo

In this study a new HPLC-DAD method for simultaneous determination of coumarin, o-coumaric acid, dihydrocoumarin and syringaldehyde in guaco extracts and pharmaceutical preparations without sample pretreatment has been developed. The chromatographic separation was carried out on a XBridge C18 (150 x 4.6mm, 5?m) column maintained at room temperature. The mobile phase consisted of water/methanol/acetonitrile/formic acid (65:30:5:1, v/v/v/v) eluted at a flow rate of 1.0 mL min-1 in an isocratic system. The validation procedures showed excellent selectivity and linearity over a range of 1.0 to 200 ?g mL-1 for all compounds (r > 0.999). The range of recovery was 97.9 to 101.8% with a RSD < 5% for intra-day and inter-day precision. The robustness study indicated that flow rate was the only critical factor. Sample analyses demonstrated a lack of standardization in the amounts of the main guaco metabolites among the evaluated samples. The new method is presented as an alternative for the quality control of guaco extracts and pharmaceutical preparations.