Column-switching high-performance liquid chromatographic determination of vancomycin in serum.
Concentrations of vancomycin in serum were measured by an automatic high-performance liquid chromatographic (HPLC) micromethod. Vancomycin is a glycopeptide antibiotic with broad application in the therapy of gram-positive infections. As this drug is potentially nephro- and ototoxic, a method to maximize its therapeutic benefit while minimizing the risk of toxicity is desirable. This fully automated HPLC method did not involve a sample pretreatment step. The configuration of the apparatus permitted a solid phase extraction of the serum sample on two precolumns filled with a reversed-phase material, followed by a chromatographic separation of the sample constituents on an analytical column. The reversed phase analytical column (muBondapak C18) was flushed with a mobile phase of water-acetonitrile-triethylamine, 870: 130: 4 (vol/vol/vol); the pH was adjusted to 3.0 with orthophosphoric acid. Precision was expressed as the coefficient of variation (CV), which was always < or = 4.13% for intra- and inter-assays (n = 10) in the range 2-50 micrograms/ml. We compared this specific HPLC determination to an enzyme-multiplied immunoassay (EMIT). Fifty clinical samples obtained from patients under vancomycin therapy were assayed by each method and results compared using a linear regression analysis. There was a significant correlation between results from HPLC and EMIT: EMIT = 0.51 + 1 x HPLC (r = 0.963; p < 0.0001). The rapidity and specificity of this HPLC micromethod make it suitable for use in the monitoring of serum levels of vancomycin and for use in pharmacokinetic studies of this antibiotic.
Demotes-Mainard
F
F
Department of Clinical Pharmacology and Toxicology, Hôpital Pellegrin, Bordeaux, France.
Labat
L
L
Vinçon
G
G
Bannwarth
B
B
D001322:Autoanalysis; D002511:Cephalosporins / Q000097:blood; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D007124:Immunoenzyme Techniques; D014640:Vancomycin / Q000097:blood* / Q000493:pharmacokinetics
D002511:Cephalosporins; D014640:Vancomycin