Determination of ceftazidime and cefepime in plasma and dialysate-ultrafiltrate from patients undergoing continuous veno-venous hemodiafiltration by HPLC.
We have developed and validated a new, rapid and reproducible HPLC method for the determination of cefepime and ceftazidime in plasma and dialysate-ultrafiltrate samples obtained from intensive care unit (ICU) patients undergoing continuous veno-venous hemodiafiltration (CVVHDF). The method for plasma samples involved protein precipitation with acetonitrile, followed by washing with dichloromethane to remove apolar lipophilic compounds. Dialysate-ultrafiltrate samples did not require any preparation. Separation was performed on a muBondapak C18 (30 cm x 3.9 mm x 10 microm) with UV detection. The mobile phase contained acetate buffer: ACN and was delivered at 2 ml/min. The coefficients of determination of the calibration curves were always > or = 0.998 and R.S.D.% of the response factors <10%. The intra and inter-assay precision and accuracy of the quality controls (QC) and limit of quantification (LOQ) were satisfactory in all cases. Plasma and dialysate-ultrafiltrate samples were stable at -20 and -80 degrees C for 2 months and also after three freeze/thaw cycles. Dialysate-ultrafiltrate samples were stable in the chromatographic rack for 24h at room temperature, but we recommend storing processed plasma samples at 4 degrees C until the analysis. The described method has proved to be useful to give accurate measurements of ceftazidime and cefepime in samples obtained from patients undergoing CVVHDF.
Isla
A
A
Laboratory of Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, University of the Basque Country, Paseo de la Universidad no. 7, 01006 Vitoria-Gasteiz, Spain.
Arzuaga
A
A
Maynar
J
J
Gascón
A R
AR
Solinís
M A
MA
Corral
E
E
Pedraz
J L
JL
D000900:Anti-Bacterial Agents / Q000097:blood*; D002138:Calibration; D000077723:Cefepime; D002442:Ceftazidime / Q000097:blood*; D002511:Cephalosporins / Q000097:blood*; D002851:Chromatography, High Pressure Liquid; D006440:Hemofiltration; D011786:Quality Control; D012015:Reference Standards; D015203:Reproducibility of Results
D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D000077723:Cefepime; D002442:Ceftazidime