title: One-step liquid-liquid extraction of cocaine from urine samples for gas chromatographic analysis.
abstract: An improved technique for cocaine extraction from urine samples for gas chromatographic (GC) analysis is described. Employing a simple liquid-liquid extraction (LLE) of cocaine with a mixture of ethyl ether:isopropanol (9:1) the method presents a mean recovery of 74.49%. Limit of detection (LOD) and limit of quantification (LOQ) were 5 and 20 ng/ml, respectively. The method is highly precise (coefficient of variation (CV) <8%) and linear from 20 to 2000 ng/ml. It can he applied to detect the presence of cocaine in urine as a marker of its recent use in drug abuse treatment protocols.
authors.affiliation: College of Pharmacy, Universidade Regional Integrada do Alto Uruguai e Missões, URI Av. Sete de Setembro, 1621 CEP 99700-000 Erechim, RS, Brazil.
authors.forename: Marcelo
authors.initials: M
authors.lastname: Farina
authors.forename: Maurício
authors.initials: M
authors.lastname: Yonamine
authors.forename: Ovandir A
authors.initials: OA
authors.lastname: Silva
mesh_terms: D002849:Chromatography, Gas / Q000379:methods*; D003042:Cocaine / Q000031:analogs & derivatives* / Q000302:isolation & purification / Q000652:urine*; D016001:Confidence Intervals; D004986:Ether; D006801:Humans; D015813:Substance Abuse Detection / Q000379:methods
chemical_list: D004986:Ether; C005618:benzoylecgonine; D003042:Cocaine