A simple, rapid and sensitive high-performance thin-layer chromatographic method for the simultaneous estimation of berberine and 5-fluorouracil in rabbit plasma

Abstract

The purpose of the present study was to develop a simple, rapid and sensitive high-performance thin-layer chromatography (HPTLC) method for the simultaneous estimation of 5-fluorouracil (5FU) and berberine (BER) in rabbit plasma. BER and 5-FU are currently under extensive studies for their synergistic effects in cancer chemotherapy. The HPTLC method was developed using TLC aluminum plates precoated with silica gel 60 F254 as the stationary phase. A mixture of toluene:methanol:ethyl acetate:formic acid (6:2:6:1, v/v) was used as the solvent system for development and detection was carried out at 266 nm. The method was designed to obtain the most optimum retardation factors (Rf) with best resolution. The Rf values of BER and 5-FU were 0.28 ± 0.02 and 0.57 ± 0.02, respectively. The plasma extraction was optimized using ethyl acetate. The method was validated in compliance with the USFDA guideline for bioanalytical method validation. The method was found to be linear in the range of 20 ng/spot to 300 ng/spot with R2 of 0.9964 for 5-FU and 0.9943 for BER. The lower limit for quantification (LLOQ) of BER and 5-FU in rabbit plasma were obtained as 29 ng/spot and 26 ng/spot, respectively. The stability of BER and 5-FU in plasma were confirmed during freeze-thaw cycles (−20 °C), on bench for 5 h and long term for 21 days. The proposed method was validated statistically and was precise, accurate and sensitive for the estimation of BER and 5-FU in rabbit plasma. This method can be extended for therapeutic drug monitoring and pharmacokinetic studies in rabbits.