title: Development of a method for the determination of cocaine, cocaethylene and norcocaine in human breast milk using liquid phase microextraction and gas chromatography-mass spectrometry.
abstract: Most licit and illicit substances consumed by the nursing mother might be excreted in breast milk, which may cause potential short and long term harmful effects for the breastfed infant. The extraction of substances from this matrix represents an analytical challenge due to its high protein and fat content as well as the fact that its composition changes during postpartum period. The aim of the present study was to develop a liquid phase microextraction (LPME) method for detection of the active substances: cocaine (COC), cocaethylene (CE) and norcocaine (NCOC) in human breast milk using gas chromatography-mass spectrometry (GC-MS). Validation was performed working on spiked human breast milk samples. The limits of detection (LOD) and quantification (LOQ) were of 6 and 12ng/mL, respectively, for all analytes. Calibration curves were linear over a concentration range of 12.0ng/mL-1000ng/mL (r(2)=0.99). No interferences were noticed at the retention times of interest. Within-run and between-run precision was always less or equal to 15 as % relative standard deviation, and bias ranged from 3 to 18%. Forty six milk samples were analyzed. Only one sample was confirmed to be COC positive (138ng/mL) and another one presented COC concentration near the LOD (6ng/mL). This method has shown to be a reliable alternative for the determination of cocaine, cocaethylene and norcocaine in human breast milk in the fields of clinical and forensic toxicology. LPME extraction procedure demonstrated to be a rather promising, low cost and environmental-friendly technique for the purpose of this study.
authors.affiliation: Faculty of Pharmaceutical Sciences, University of São Paulo, Brazil. Electronic address: silveirago@usp.br.
authors.forename: Gabriela de Oliveira
authors.initials: Gde O
authors.lastname: Silveira
authors.affiliation: Faculty of Pharmaceutical Sciences, University of São Paulo, Brazil.
authors.forename: Íris Tikkanen
authors.initials: ÍT
authors.lastname: Belitsky
authors.affiliation: Poison Control Center of Sao Paulo, Hospital Dr. Arthur Ribeiro de Saboya, Brazil.
authors.forename: Silvana
authors.initials: S
authors.lastname: Loddi
authors.affiliation: Poison Control Center of Sao Paulo, Hospital Dr. Arthur Ribeiro de Saboya, Brazil.
authors.forename: Carolina Dizioli
authors.initials: CD
authors.lastname: Rodrigues de Oliveira
authors.affiliation: Poison Control Center of Sao Paulo, Hospital Dr. Arthur Ribeiro de Saboya, Brazil.
authors.forename: Alexandre Dias
authors.initials: AD
authors.lastname: Zucoloto
authors.affiliation: Poison Control Center of Sao Paulo, Hospital Dr. Arthur Ribeiro de Saboya, Brazil.
authors.forename: Ligia Veras Gimenez
authors.initials: LV
authors.lastname: Fruchtengarten
authors.affiliation: Faculty of Pharmaceutical Sciences, University of São Paulo, Brazil.
authors.forename: Mauricio
authors.initials: M
authors.lastname: Yonamine
mesh_terms: D003042:Cocaine / Q000031:analogs & derivatives / Q000032:analysis* / Q000097:blood; D005260:Female; D005554:Forensic Medicine; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D059627:Liquid Phase Microextraction; D008895:Milk, Human / Q000737:chemistry*; D015203:Reproducibility of Results; D015813:Substance Abuse Detection / Q000379:methods*
chemical_list: C008671:norcocaine; C066444:cocaethylene; D003042:Cocaine
keywords: Breast milk; Cocaine; Gas chromatography mass spectrometry; Infant; Liquid phase microextraction