High-performance liquid chromatographic determination of naltrexone in plasma of hemodialysis patients.
A simple, sensitive, selective and reliable reversed-phase high-performance liquid chromatographic (HPLC) method with UV detection is described for the determination of naltrexone in plasma samples. Naltrexone and the internal standard, naloxone, were isolated from plasma either with a liquid-liquid extraction method using ethyl acetate or with a solid-phase extraction method using Sep-Pack C18 cartridge before chromatography. The extracts were dried under a stream of nitrogen and the samples were reconstituted in the mobile phase, then 20 microL were injected on a Waters Symmetry C18 column (5 microm particle size, 4.6 x 150 mm). The mobile phase consisted of 0.06% triethylamine (pH 2.8)-acetonitrile (92:8, v/v) pumped at 1 mL/min. The peak-area ratio versus plasma concentration was linear over the range of 10-500 ng/mL and the detection limit was less than 8 ng/mL. Quantification was by ultra-violet detection at 204 nm. The present method was applied to the determination of the plasma concentration of naltrexone in dialyzed patients. Patients (n = 8) with severe generalized pruritus received 50 mg of naltrexone orally per day for 2 weeks. The variability in the therapeutic response in treated patients required plasma concentration investigations of this opioid antagonist.
Kambia
K
K
Laboratoire de Pharmacologie, Pharmacocinétique et Pharmacie clinique, Faculté des Sciences Pharmaceutiques et Biologiques, Lille, France.
Bah
S
S
Dine
T
T
Azar
R
R
Odou
P
P
Gressier
B
B
Luyckx
M
M
Brunet
C
C
Ballester
L
L
Cazin
M
M
Cazin
J C
JC
D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications / Q000628:therapy; D009271:Naltrexone / Q000097:blood* / Q000627:therapeutic use; D009292:Narcotic Antagonists / Q000097:blood* / Q000627:therapeutic use; D011537:Pruritus / Q000188:drug therapy / Q000209:etiology; D006435:Renal Dialysis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D009292:Narcotic Antagonists; D009271:Naltrexone