title: Determination of trimethoprim, sulphamethoxazole and its N4-acetyl metabolite in biological fluids by high-performance liquid chromatography.
abstract: A normal-phase high-performance liquid chromatographic method was developed to determine therapeutic concentrations of trimethoprim, sulphamethoxazole, and its N4-acetyl derivative in biological fluids. The compounds are extracted at pH 6.2 using ethyl acetate--chloroform in a single extraction. The detection limit is 15 ng/ml for trimethoprim, 20 ng/ml for sulphamethoxazole, and 10 ng/ml for its N4-acetyl metabolite. The method is rapid, sensitive, precise, and well suited to clinical pharmacokinetic investigations.
mesh_terms: D000368:Aged; D002021:Buffers; D002851:Chromatography, High Pressure Liquid; D004338:Drug Combinations / Q000097:blood; D005260:Female; D006801:Humans; D007700:Kinetics; D008297:Male; D012997:Solvents; D013420:Sulfamethoxazole / Q000031:analogs & derivatives* / Q000097:blood* / Q000302:isolation & purification* / Q000378:metabolism; D013997:Time Factors; D014295:Trimethoprim / Q000097:blood* / Q000302:isolation & purification* / Q000378:metabolism; D015662:Trimethoprim, Sulfamethoxazole Drug Combination
chemical_list: D002021:Buffers; D004338:Drug Combinations; D012997:Solvents; C021282:N(4)-acetylsulfamethoxazole; D015662:Trimethoprim, Sulfamethoxazole Drug Combination; D014295:Trimethoprim; D013420:Sulfamethoxazole