Analysis of curcumin and piperine in biological samples by reversed-phase liquid chromatography with multi-wavelength detection

• A reversed-phase HPLC method was developed to analyze both curcumin and piperine. • Emodin was the internal standard, and multi-wavelength detection was employed. • Baseline resolution of curcumin, piperine and emodin was obtained in less than 4 min. • The detection limits were in the low ng/mL range for curcumin and piperine. • This method has been used in various samples, such as human serum and cell lysates. Widely accessible food phytochemicals such as curcumin have been reported to have anti-inflammatory and anticarcinogenic properties. However, curcumin has poor absorption in the gut, and piperine has been of interest as a dietary compound that can enhance curcumin bioavailability. The aim of this study was to develop and optimize a technique using reversed-phase chromatography with multi-wavelength detection for the simultaneous measurement of curcumin and piperine in various biological matrices. Emodin was used as an internal standard. Protein precipitation and liquid-liquid extraction based on acetonitrile provided good recovery of these analytes. A 150 mm × 4.6 mm I.D. Luna C18 column was used under isocratic conditions to separate curcumin, piperine, and emodin with baseline resolution, and with good separation from other sample components, in as little as 4 min. The detection limits for curcumin and piperine were 3 and 7 ng/mL, respectively. This method has been used to quantitate these compounds in samples such as human intestinal epithelial cell lysates and mouse plasma or GI tissues in research aimed at examining the bioavailability of curcumin in the presence of piperine.