Zinc complex-based determination of rutin in dietary supplements

Abstract

The aim of this study was to develop and validate a simple, rapid, sensitive and low-cost method for determination of rutin in tablets. The proposed spectrophotometric method is based on the formation of the Zn2+-rutin complex in methanol 70% (v/v) at pH 8.52, and detection at lambda(max)= 410 nm. The concentration range over which the response was linear was 0.3-12.2 mu g ml(-1). The limit of detection (LOD) and the limit of quantification (LOQ) were 0.21 mu g ml(-1) and 0.63 mu g ml(-1), respectively. The proposed method was successfully applied to the determination of rutin in herbal dietary supplements. The reliability of the method was checked by comparison with results obtained by the established RP-HPLC/UV method. The proposed method fulfills all aimed requirements.