High-performance liquid chromatography of nalbuphine, butorphanol and morphine in blood and brain microdialysate samples: application to pharmacokinetic/pharmacodynamic studies in rats.
A rapid and sensitive assay for quantification of nalbuphine, butorphanol and morphine in blood (50 microL) and brain microdialysate ( approximately 40 microL) samples was developed. Blood samples were extracted with ethyl acetate. Analysis was performed with high-performance liquid chromatography (HPLC) coupled to an electrochemical detector. The mobile phase was a mixture of 0.1 M sodium phosphate buffer, methanol and octane-sulfonic acid with ratio and pH depending on compound and matrix. The limits of quantification in blood samples were 25, 50 and 25 ng/mL for nalbuphine, butorphanol and morphine, respectively and 0.5 ng/mL for morphine in microdialysate samples. Based on sample volume, sensitivity and reproducibility, these assays are particularly suitable for pharmacokinetic/pharmacodynamic studies in rodents.
Leiden Amsterdam Center for Drug Research, Leiden University, Division of Pharmacology, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
Dorien
D
Groenendaal
Margret C M
MC
Blom-Roosemalen
Meindert
M
Danhof
Elizabeth C M de
EC
Lange
D000818:Animals; D002077:Butorphanol / Q000032:analysis* / Q000097:blood; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D008297:Male; D017551:Microdialysis; D009020:Morphine / Q000032:analysis* / Q000097:blood; D009266:Nalbuphine / Q000032:analysis* / Q000097:blood; D009294:Narcotics / Q000493:pharmacokinetics*; D051381:Rats; D017208:Rats, Wistar; D015203:Reproducibility of Results
D009294:Narcotics; D009020:Morphine; D009266:Nalbuphine; D002077:Butorphanol