Measurement and pharmacokinetic analysis of unbound cephaloridine in rat blood by on-line microdialysis and microbore liquid chromatography.
A technique involving rapid sampling of cephaloridine in rat blood was achieved using a combination of microdialysis and sensitive microbore liquid chromatography. A microdialysis probe was inserted into the jugular vein/right atrium of a Sprague-Dawley rat. Then after a real-time collection of the analyte by microdialysis, the dialysate was automatically injected into a liquid chromatographic system via an on-line injector. Following a 2 h stabilization period after the surgical procedure, cephaloridine (20 mg/kg, i.v.) was then administered via the femoral vein. Isocratic elution of cephaloridine was carried out with a mobile phase containing methanol-20 mM monosodium phosphate (25:75, v/v, pH 5.5), and the flow rate of the mobile phase was 0.05 mL/min within 10 min. Intra- and inter-assay accuracy and precision of the assay were each less than 10%. The in vivo recovery of the cephaloridine from the microdialysate was 49.7 +/- 8.0% and 42.4 +/- 8.4% for 0.5 and 1 microg/mL standards (n = 6), respectively. Based on the pharmacokinetic analysis, the elimination half-life was 32.2 +/- 8.6 min by cephaloridine administration (20 mg/kg, i.v., n = 6).
National Research Institute of Chinese Medicine, 155-1 Li-Nong Street Section 2, Taipei 112, Taiwan. thtsai@cma23.nricm.edu.tw
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Tsai
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Kao
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Chen
D000818:Animals; D002509:Cephaloridine / Q000097:blood* / Q000493:pharmacokinetics; D002511:Cephalosporins / Q000097:blood* / Q000493:pharmacokinetics; D002853:Chromatography, Liquid / Q000379:methods*; D008297:Male; D017551:Microdialysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results
D002511:Cephalosporins; D002509:Cephaloridine