[Determination of biapenem in human plasma by high performance liquid chromatography]

To establish a method to determine biapenem in human plasma with high performance liquid chromatography.

Chromatographic separation was performed on a YMC-C18 column (150 mmX 4. 6 mm, 5 microm) eluted with a mobile phase comprising 98 : 2 (V = V) of sodium acetate (0.1 mol/L, adjust with acetic acid to pH 4.5) and acetonitrile with a flow rate of 1.0 mL/min. The detection wavelength was set at 300 nm. Temperature was controlled at 35 degrees C. The plasma samples were precipitated with acetonitrile. The supernatant was vortexed with dichloromethane and 0.03 mL of the aqueous layer was injected for analysis.

The method was valid to detect biapenem in a range of 0.0625 mg/L to 80 mg/L (correlation coefficient 0.999). The pretreatment recovery of biapenem ranged from 96.11% to 98.76%. The methodological recovery of biapenem ranged from 99.14% to 109.69%. The inter-day RSD ranged from 0.92% to 2.79%. The intra-day RSD ranged from 2.46% to 4.08%. Less than 7% change of results was observed after the sample was stored in room temperature for 5 h, frozen and defrozen 3 times, stored at -30 degrees C for 28 d, stayed in autosampler for 24 h, and injected twice.

The method is sensitive, accurate and easy to perform, which offers a satisfactory tool for the determination and pharmacokinetic study of biapenem.