RP-LC-UV Determination of Proanthocyanidins in <i>Guazuma ulmifolia</i>
A simple, reproducible, and efficient liquid chromatographic method was developed with UV detection. Water (0.05% TFA):acetonitrile (0.05% TFA) was used as the mobile phase in a gradient system for the determination of procyanidin B2 (PB2) and epicatechin (EC) in the bark of Guazuma ulmifolia Lam. The analysis was performed using a Phenomenex Gemini RP C 18 column (5 μm) as stationary phase, at 30 °C, with a flow rate of 0.8 mL min −1 , at a wavelength of 210 nm for detection and determination. The main validation parameters of the method were also determined. Calibration curves were found to be linear, with ranges of 20.00–150.00 (PB2) and 10.00–110.00 μg mL −1 (EC). The correlation coefficients of linear regression analysis were between 0.9981 and 0.9988, and the detection limits were between 2.89 and 2.54 μg mL −1 . The contents of PB2 and EC were successfully determined, with satisfactory reproducibility and recovery. Recoveries of the PB2 and EC were 103.00 and 104.01%, respectively. The method was successfully applied to the determination of procyanidins in the bark of G. ulmifolia .