title: Matrix solid-phase dispersion on column clean-up/pre-concentration as a novel approach for fast isolation of abuse drugs from human hair.
abstract: A simple and fast sample pre-treatment method based on matrix solid-phase dispersion (MSPD) for isolating cocaine, benzoylecgonine (BZE), codeine, morphine and 6-monoacethylmorphine (6-MAM) from human hair has been developed. The MSPD approach consisted of using alumina (1.80 g) as a dispersing agent and 0.6M hydrochloric acid (4 mL) as an extracting solvent. For a fixed hair sample mass of 0.050 g, the alumina mass to sample mass ratio obtained was 36. A previously conditioned Oasis HLB cartridge (2 mL methanol, plus 2 mL ultrapure water, plus 1 mL of 0.2M/0.2M sodium hydroxide/boric acid buffer solution at pH 9.2) was attached to the end of the MSPD syringe for on column clean-up of the hydrochloric acid extract and for transferring the target compounds to a suitable solvent for gas chromatography (GC) analysis. Therefore, the adsorbed analytes were directly eluted from the Oasis HLB cartridges with 2 mL of 2% acetic acid in methanol before concentration by N(2) stream evaporation and dry extract derivatization with N-methyl-tert-butylsilyltrifluoroacetamide (BSTFA) and chlorotrimethylsilane (TMCS). The optimization/evaluation of all the factors affecting the MSPD and on column clean-up procedures has led to a fast sample treatment, and analytes extraction and pre-concentration can be finished in approximately 30 min. The developed method has been applied to eight hair samples from poli-drug abusers and measured analyte concentrations have been found to be statistically similar (95% confidence interval) to those obtained after a conventional enzymatic hydrolysis method (Pronase E).
authors.affiliation: Department of Analytical Chemistry, Nutrition and Bromatology, Faculty of Chemistry, University of Santiago de Compostela, Avenida das Ciencias, s/n. 15782, Santiago de Compostela, Spain.
authors.forename: Martha
authors.initials: M
authors.lastname: Míguez-Framil
authors.forename: Antonio
authors.initials: A
authors.lastname: Moreda-Piñeiro
authors.forename: Pilar
authors.initials: P
authors.lastname: Bermejo-Barrera
authors.forename: Iván
authors.initials: I
authors.lastname: Alvarez-Freire
authors.forename: María Jesús
authors.initials: MJ
authors.lastname: Tabernero
authors.forename: Ana María
authors.initials: AM
authors.lastname: Bermejo
mesh_terms: D003042:Cocaine / Q000032:analysis / Q000302:isolation & purification*; D008401:Gas Chromatography-Mass Spectrometry; D006197:Hair / Q000737:chemistry*; D006801:Humans; D006851:Hydrochloric Acid; D013287:Illicit Drugs / Q000032:analysis / Q000302:isolation & purification*; D000432:Methanol; D009020:Morphine / Q000032:analysis / Q000302:isolation & purification*; D015999:Multivariate Analysis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D052616:Solid Phase Extraction / Q000379:methods*
chemical_list: D013287:Illicit Drugs; D009020:Morphine; D003042:Cocaine; D006851:Hydrochloric Acid; D000432:Methanol