Development of a validated HPLC method for the simultaneous determination of flavonoids in Cuscuta chinensis Lam. by ultra-violet detection

In the present study, a fast, simple and reliable method for the simultaneous determination and quantization of C. chinensis flavonols including hyperoside, rutin, isorhamnetin and kaempferol has been developed.The chromatographic separation was carried out on a reversed phase ACE 5 C18 with eluting at a flow rate of 1 ml/min using a gradient with O-phosphoric acid 0.25% : acetonitrile for 42 min. UV spectra were collected across the range of 200–900 nm, extracting 360 nm for the chromatograms. The method was validated according to linearity, selectivity, precision, recovery, LOD and LOQ.The method was selective for determination of rutin, hyperoside, isorhamnetin and kampferol. The calibration graphs of flavonols were linear with r2？>？0.999. RSDs% of intra- and inter-day precisions were found 1.3&3.4 for rutin, 1.5&2.8 for hyperoside, 1.3&3.3 for isorhamnetin and 1.7 & 2.9 for kaempferol which were satisfactory. LODs and LOQs were calculated as 1.73 & 8.19 for rutin, 0.09 & 4.19 for hyperoside, 2.09 & 6.3 for isorhamnetin and 0.18 & 0.56 for kaempferol. The recovery averages of above-mentioned flavonols were 90.3%, 97.4%, 98.7% and 90.0%, respectively.The simplicity of the method makes it highly valuable for quality control of C. chinensis according to quantization of flavonols.Cuscuta is a genus consisted of about 100–170 species of yellow, orange, red and rarely green parasitic plants which is the only genus in the family of Cuscutaceae. Cuscuta Semen, a crude drug prepared from the seeds of Cuscuta chinensis Lam., is commonly used in traditional medicine as a liver and kidney tonic [1]. Many investigations have been established different biological activity of this plant such as improving sexual function [2], anti-cancer [3], immunostimulatory [4-7] and antioxidant activities [7]. The active constituents of the C. chinensis are including flavonoids, lignans, quinic acid derivatives and polysaccharides [1,8-10]. These compounds have been suggested to be responsib