title: Determination of cocaine/crack biomarkers in colostrum by LC-MS following protein precipitation.
abstract: Drug abuse by nursing mothers is an ongoing concern because it may cause many adverse effects to the newborns. The development of analytical methods to analyze drugs of abuse in colostrum (first milk produced after birth) has a huge importance, because it enables the monitoring and the correct follow-up to users and newborns. A liquid chromatography mass spectrometry (LC-MS) method was developed and validated for the determination of cocaine and smoked cocaine (crack) biomarkers in colostrum. Cocaine (COC) and its major metabolite benzoylecgonine (BZE), the pyrolytic products anhydroecgonine methyl ester (AEME) and anhydroecgonine (AEC) were analyzed after a simple protein precipitation procedure using atropine (ATP) as internal standard (IS). Applying a chemometric approach study, all peaks were chromatographically separated at isocratic condition with a Kinetex HILIC column for polar compounds, at 30°C in 12min. One ion was detected for the quantification and three ions for confirmation of each analyte. The method was linear for all analytes in the concentration range of 5-300ng/mL with correlation coefficients (r) between 0.9983 and 0.9996. The lower limit of quantification (LLOQ) was 5ng/mL with acceptable validation parameters. Matrix effect was assessed by post-extraction addition approach and showed good results, demonstrating that protein precipitation cleaning procedure is fast, reliable and demand small quantities of organic solvent. The LC-MS method is fast and cheap compared to other equipments and was also successfully applied to assess real samples of colostrum from nursing mothers who were suspect of cocaine/crack abuse.
authors.affiliation: Postgraduate Program in Pharmaceutical Sciences, Federal University of Rio Grande do Sul, Av. Ipiranga 2752, 90610-000 Porto Alegre, RS, Brazil. Electronic address: felipebdavila@hotmail.com.
authors.forename: Felipe Bianchini
authors.initials: FB
authors.lastname: D'Avila
authors.affiliation: Postgraduate Program in Pharmaceutical Sciences, Federal University of Rio Grande do Sul, Av. Ipiranga 2752, 90610-000 Porto Alegre, RS, Brazil.
authors.forename: Andrea Garcia
authors.initials: AG
authors.lastname: Pereira
authors.affiliation: Postgraduate Program in Pharmaceutical Sciences, Federal University of Rio Grande do Sul, Av. Ipiranga 2752, 90610-000 Porto Alegre, RS, Brazil.
authors.forename: Fernanda Rodrigues
authors.initials: FR
authors.lastname: Salazar
authors.affiliation: Postgraduate Program in Pharmaceutical Sciences, Federal University of Rio Grande do Sul, Av. Ipiranga 2752, 90610-000 Porto Alegre, RS, Brazil.
authors.forename: Pâmela Lukasewicz
authors.initials: PL
authors.lastname: Ferreira
authors.affiliation: Santa Casa de Caridade de Bagé, Av. Gomes Carneiro 1350, 96400-130, Bagé, RS, Brazil.
authors.forename: Cledinara Rodrigues
authors.initials: CR
authors.lastname: Salazar
authors.affiliation: Postgraduate Program in Pharmaceutical Sciences, Federal University of Rio Grande do Sul, Av. Ipiranga 2752, 90610-000 Porto Alegre, RS, Brazil.
authors.forename: Renata Pereira
authors.initials: RP
authors.lastname: Limberger
authors.affiliation: Postgraduate Program in Pharmaceutical Sciences, Federal University of Rio Grande do Sul, Av. Ipiranga 2752, 90610-000 Porto Alegre, RS, Brazil.
authors.forename: Pedro Eduardo
authors.initials: PE
authors.lastname: Fröehlich
mesh_terms: D015415:Biomarkers / Q000378:metabolism*; D002845:Chromatography / Q000379:methods*; D019970:Cocaine-Related Disorders / Q000378:metabolism*; D003126:Colostrum / Q000378:metabolism*; D016578:Crack Cocaine; D006801:Humans; D057230:Limit of Detection; D013058:Mass Spectrometry / Q000379:methods*; D015203:Reproducibility of Results
chemical_list: D015415:Biomarkers; D016578:Crack Cocaine
keywords: Breast milk (colostrum); Cocaine/crack; HILIC column; LC–MS; Protein precipitation