Development and Validation of a High-Performance Liquid Chromatography-Based Method for Catechin Isolated from the Leaves of Gambir (Uncaria gambir Roxb)

Gambir (Uncaria gambir Roxb) has long been thought to provide various health benefits due to the main secondary metabolite, catechin. The high catechin content makes gambir a strong antioxidant. The present study was conducted to develop and validate the quantification of catechin in gambir leaves by high-performance liquid chromatography (HPLC). The method was performed using a 100 mL sample with dilution. The separation process employed a Sunfire C18 (150 mm × 4.6 mm) column, the mobile phase was composed of solvent A: 0.03% trifluoroacetic acid in acetonitrile-water (5:95) and solvent B: 0.1% trifluoroacetic acid in acetonitrile at a 0.45 mL/min flow rate. The validation was conducted by measuring the accuracy, precision, linearity, limit of detection (LOD), limit of quantification (LOQ), and robustness. The results showed that the percent recovery was 98.30-99.82% with a precision value of 0.28% RSD, good linearity with a 0.9996 R-value, 2.7 µg/mL of LOD, and 8.3 µg/mL of LOQ. There was no significant difference between changes in the mobile phase of 4% (comparison of area and retention time), and 6% (comparison of area). However, the results also demonstrated that the mobile phase was not resistant to changes in the mobile phase of 6% in the ratio of retention time because of the shift in retention time that was faster than the catechin standard. The findings of this study reveal that this method satisfies the validation requirements for accuracy, precision, linearity, and robustness tests, therefore, the HPLC-based method can be applied to analyze catechin in gambir leaves.