Paper Title
Evaluation on Eugenol Content in Some Thai Traditional Medicine Samples By Reverse-Phase High Performance Liquid Chromatography (RP-HPLC)

Abstract
A sensitive RP-HPLC method with ultra-violet (UV) detection has been developed for determination of eugenol in commercials of Thai traditional medicine. Analysis of samples were performed on RP-C18 column and eluated with isocratic system by methanol and water (63:37, v/v) as mobile phase system and at 1.0 ml/min flow rate. The eluate was detected at 280 nm. This method was applied to analyse eugenol content in 10 commercials of Thai traditional medicine. The results showed that eugenol peak was detected at 9.6 minute. The linearity of calibration curve was in the range of 1-100 μg/mL. The limit of detection (LOD) and limit of quantitation (LOQ) were 0.02 μg/mL and 0.005 μg/mL respectively. A simple, precise and accurate HPLC-UV method has been developed for the determination of eugenol in 10 commercials of Thai traditional medicine samples. Its revealed that eugenol could be detected in Thai traditional medicine in the range of 0.17-95.84 μg/mL. Keyword� Eugenol,High Performance Liquid Chromatography, Thai traditional medicine.