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

作者：Silveira Gabriela de Oliveira^*; Belitsky Iris Tikkanen; Loddi Silvana; Rodrigues de Oliveira Carolina Dizioli; Zucoloto Alexandre Dias; Gimenez Fruchtengarten Ligia Veras; Yonamine Mauricio

来源：Forensic Science International, 2016, 265: 22-28.

DOI：10.1016/j.forsciint.2016.01.007

• Breast milk
• Liquid phase microextraction
• Infant
• Gas chromatography mass spectrometry
• Cocaine

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 12 ng/mL, respectively, for all analytes. Calibration curves were linear over a concentration range of 12.0 ng/mL-1000 ng/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 (138 ng/mL) and another one presented COC concentration near the LOD (6 ng/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.

• 出版日期2016-8