Abstract: AIM: To establish an HPLC-UV assay for determining plasma concentration of S-Adenosylmethionine (SAMe) and to study its pharmacokinetics in rats. METHODS: The chromatographic conditions were as follows: a Kromasil C₁₈ column (4.6 mm×200 mm , 5 μm) ,a flow rate of 0.6 mL/min for the mobile phase of methanol/0.3% trifluoroacetic acid (V/V) (dissolve 1% phosphate buffer) (2∶98) , an isocratic elution mode was carried out at column temperature (30 ℃) and the UV detection at the wavelength of 260 nm. 140 mg/kg SAMe was administrated by intravenous and plasma concentration were determined by HPLC-UV assay. RESULTS: SAMe was successfully separated. The calibration curve showed a good linear regression within the range of 10-2000 μg/mL. The regression equation was Y=30241X+256204, r=0.9991. The precision of intra-assay and inter-assay were 2.6%, 3.6%, 3.9% and 6.3%, 4.9%, 7.9%, respectively. The average extraction recovery was 107%, 101%, 98.3%, respectively. The pharmacokinetic parameter were AUC_(0-t) (569.52±174.87) mg·L^-1·h,t_1/2 (2.03±0.96) h, CL (0.21±0.13) L·h^-1·kg^-1, V_d (0.53±0.31) L/kg, respectively.CONCLUSION: This method was proved to be simple and efficient with excellent specificity, sensitivity, precision, recovery and can be applied to pharmacokinetic investigation of SAMe.

Key words: S-Adenosylmethionine, HPLC-UV, Pharmacokinetics