Simultaneous measurement of nicotinic acid and its major metabolite, nicotinuric acid in urine using high-performance liquid chromatography: application of solid-liquid extraction.
The concentrations of nicotinic acid (NiAc) and nicotinuric acid (NiUAc), a major metabolite of NiAc, were simultaneously determined in urine using solid-phase extraction (cation-exchange extraction) and reversed-phase high-performance liquid chromatography with ultraviolet detection. The intra- and inter-day precision studies showed good reproducibilities: the coefficients of variations were less than 8.1% for NiAc and 8.8% for NiUAc. The calibration curves were linear (r2 > 0.9934) in the concentration range 10-1000 micrograms/ml. The removal of endogenous interferences in urine by solid-phase extraction presented here is superior to the pretreatment protocols reported previously by other workers. The method was used in a preliminary pharmacokinetic study in rats after intravenous administration of NiAc (5 and 15 mg/kg).
Iwaki
M
M
Faculty of Pharmaceutical Sciences, Kinki University, Osaka, Japan.
Ogiso
T
T
Hayashi
H
H
Lin
E T
ET
Benet
L Z
LZ
D000818:Animals; D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D008297:Male; D009539:Nicotinic Acids / Q000378:metabolism / Q000493:pharmacokinetics / Q000652:urine*; D051381:Rats; D017208:Rats, Wistar; D013048:Specimen Handling
D009539:Nicotinic Acids; C002477:nicotinuric acid