title: Determination of unbound ceftriaxone in rat blood by on-line microdialysis and microbore liquid chromatography.
abstract: In vivo microdialysis was used to determine unbound ceftriaxone in rat blood. A microdialysis probe was inserted into the jugular vein/right atrium of Sprague-Dawley rats, and dose of 10 mg/kg ceftriaxone was then administered via the femoral vein. Dialysates were automatically collected and injected into a liquid chromatographic system via an on-line injector. Isocratic elution of ceftriaxone within 10 min was achieved using a microbore liquid chromatographic system. The chromatographic mobile phase consisted of methanol-100 mM monosodium phosphoric acid (15:85, v/v, pH 7.0). The wavelength of the UV detector was set at 280 nm. Intra- and inter-assay accuracy and precision of the assay were less than 15%. The detection limit of ceftriaxone was 20 ng/ml. The results suggest that unbound ceftriaxone in rat blood is best fit to a biexponential decay model.
authors.affiliation: Department of Pharmacology, National Research Institute of Chinese Medicine, 155-1, Section 2 Li-Nong Street, Taipei, Taiwan. thtsai@cma23.nricm.edu.tw
authors.forename: T H
authors.initials: TH
authors.lastname: Tsai
authors.forename: F C
authors.initials: FC
authors.lastname: Cheng
authors.forename: L C
authors.initials: LC
authors.lastname: Hung
authors.forename: C F
authors.initials: CF
authors.lastname: Chen
mesh_terms: D000818:Animals; D002443:Ceftriaxone / Q000097:blood*; D002853:Chromatography, Liquid; D007262:Infusions, Intravenous; D008297:Male; D017551:Microdialysis; D011485:Protein Binding; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013047:Specific Pathogen-Free Organisms; D013997:Time Factors
chemical_list: D002443:Ceftriaxone