Determination of methylguanidine in plasma and urine by high-performance liquid chromatography with fluorescence detection following postcolumn derivatization.
A high-performance liquid chromatographic method was developed for the determination of methylguanidine in biological fluids. Methylguanidine and the internal standard were isolated from plasma by cation-exchange solid-phase extraction prior to chromatographic analysis. Urine samples were diluted and injected directly onto the analytical column. Chromatographic separation was carried out on an Ultrasil cation-exchange column using a mixture of methanol and monochloroacetate (15/85, v/v) as the mobile phase. Postcolumn derivatization of methylguanidine was carried out using alkaline ninhydrin reagent and the resulting fluorescent product was detected on-line. The method was specific, sensitive, reproducible, and linear over a wide a range of concentrations. The lower limit of detection for methylguanidine in plasma and urine was 1 and 100 ng/ml, respectively. The method was successfully employed for quantification of the levels of methylguanidine in normal and uremic human subjects, normal dogs, and dogs with ischemic-induced acute or spontaneous chronic renal failure.
Boppana
V K
VK
Department of Drug Metabolism, Smith Kline & French Laboratories, King of Prussia, Pennsylvania 19406-0939.
Rhodes
G R
GR
Brooks
D P
DP
D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002852:Chromatography, Ion Exchange / Q000379:methods; D004285:Dogs; D006146:Guanidines / Q000032:analysis*; D006801:Humans; D008760:Methylguanidine / Q000032:analysis*; D009555:Ninhydrin; D014511:Uremia / Q000097:blood / Q000652:urine
D006146:Guanidines; D008760:Methylguanidine; D009555:Ninhydrin