Application of HPLC and response surface methodology for simultaneous determination of curcumin and desmethoxy curcumin in Curcuma syrup formulation

Abstract

The effectiveness of herbal medicine containing Curcuma extract depends on the active compounds of curcumin (CUK) and desmethoxycurcumin (DMCUR) present in formulation. The objective of this study was to optimize HPLC condition using experimental design of Box-Behnken design (BBD) for simultaneous determination of C and DMC in syrup containing curcuma extract. The column used was RP 18 Waters® X-Bridge (250 x 4.6 mm i.d.; 5 μm). Four variables namely column temperature, flow rate, solvent ratio of acetonitrile-acetic acid, and % acetic acid were used and subjected to RSM in order to get optimum condition. The predicted optimum assay condition consisted of mobile phase acetonitrile-acetic acid 4.08% (49: 51) delivered isocratically at flow rate 1.04 mL/min with column temperature of 40°C. Using this optimum condition, baseline separation of both compounds was achieved with good resolution. The optimized HPLC assay condition was validated according to International conference on Harmonization (ICH) guidelines by assessing several parameters such as specificity, linearity, accuracy, sensitivity and precision.