title: Determination of unbound cefamandole in rat blood by microdialysis and microbore liquid chromatography.
abstract: To analyze unbound cefamandole in rat blood, a method combing microdialysis with microbore liquid chromatography has been developed. A microdialysis probe was inserted into the jugular vein/right atrium of male Sprague-Dawley rats to examine the unbound cefamandole level in the rat blood following cefamandole administration (50 mg/kg, i.v.). The dialysates were directly submitted to a liquid chromatographic system. Samples were eluted with a mobile phase containing acetonitrile-methanol-100 mM monosodium phosphate (pH 5.0; 15:20:65, v/v). The UV wavelength was set at 270 nm for monitoring the analyte. Using the retrograde method, at infusion concentrations of 1 microg/mL of cefamandole, the in vivo microdialysis recoveries were 55.44% for the rat blood (n = 6). Intra- and inter-assay accuracy and precision of the analyses were < or = 10% in the range of 0.1-10 microg/mL. Pharmacokinetic parameters were calculated from the recovery-corrected dialysate concentrations of cefamandole vs time data. The elimination half-life (t1/2,beta) was 21.6 +/- 1.6 min. The results suggest that the pharmacokinetics of unbound cefamandole in blood following cefamandole administration (50 mg/kg, i.v., n = 5) fit best to the two-compartmental model.
authors.affiliation: Institute of Pharmacology, National Yang-Ming University, Taipei 112, Taiwan.
authors.forename: P H
authors.initials: PH
authors.lastname: Yeh
authors.forename: C H
authors.initials: CH
authors.lastname: Lee
authors.forename: F C
authors.initials: FC
authors.lastname: Cheng
authors.forename: T H
authors.initials: TH
authors.lastname: Tsai
mesh_terms: D000818:Animals; D019540:Area Under Curve; D002435:Cefamandole / Q000097:blood* / Q000493:pharmacokinetics; D002511:Cephalosporins / Q000097:blood* / Q000493:pharmacokinetics; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006207:Half-Life; D008297:Male; D017551:Microdialysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D013056:Spectrophotometry, Ultraviolet
chemical_list: D002511:Cephalosporins; D002435:Cefamandole