Development of UPLC-MS/MS Method for Quantitative Analysis of Curcumin in Human Plasma

A specific, very rapid, and sensitive ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/ MS) method for quantitative analysis of curcumin in human plasma has been developed and validated. Diazepam was used as internal standard (IS). The analytes were isolated using liquid-liquid extraction method with the mixture of ethyl acetate-methanol (95: 5). The organic solvents were evaporated, reconstituted in mobile phase, and injected to UPLC completed with UPLC BEH C18 column 1.7 mu m, 2.1 x 100 mm Acquity (R) Waters as stationary phase, mixture of 0.15% formic acid-acetonitril (50:50, v/v) as mobile phase, and flow rate of 0.5 mL/min and detected in positive ionization mode tandem mass spectrometer operated in multiple reaction monitoring (MRM). The MS/MS ion transitions monitored were m/z 369.05 -> 176.95 and 284.95 -> 193 for curcumin and IS, respectively. The retention times for curcumin and IS were 1.7 and 1.4 min, respectively, and the linearity range was 1-100 ng/mL with a coefficient correlation (r) of 0.999 and lower limit of quantitation (LLOQ) of 1 ng/mL. The relative standard deviation (RSD) values of the intra-and inter-assay precisions of the method were below 8.3% and 12.7%, respectively, while the accuracy ranged from 89.5 to 98.7% and the extraction recovery of curcumin and IS was up to 86.6%. The data presented show that the method provides specific, very rapid, sensitive, precise, and accurate measurements of curcumin concentrations in human plasma.