A rapid, sensitive, and reproducible RP-HPLC method was developed for the determination of two constituents in Ammannia multiflora, namely, tetralone-4-O-β-D-glucopyranoside (1) and 4-hydroxy-α-tetralone (2). The samples were separated on a Spherisorb ODS2 column (250×4.6 mm, i.d., 10 μm) and binary elution of water and methanol (2 : 3) with flow rate of 0.8 mL/min at λ 254 nm. The LOD and LOQ were found 0.05 and 0.18 μg/mL for compound 1 and 0.06 and 0.18 μg/mL for compound 2, respectively. All calibration curves showed good linearity (r2>0.999) within test ranges for both the analytes. The RSD values for intra-and inter-day precisions were less than 1.1%. The successful application of the developed method on five different samples revealed an average 0.0206% and 0.7636% (w/w) of compounds 1 and 2, respectively in A. multiflora indicating that the developed LC assay method may be readily utilized as a quality control method for the plant.
Quality-control method for the determination of biological activity of engineered calcineurin subunit B
