Efficient extraction method using magnetic carbon nanotubes to analyze cocaine and benzoylecgonine in breast milk by GC/MS

Aim: The increasing use of cocaine (COC) during breastfeeding has led to growing concern about exposure of infants. Therefore, to study this exposure, a new method to analyze COC and benzoylecgonine in breast milk was developed. Methodology: A new extraction method was used for the first time to analyze COC and its major metabolite, benzoylecgonine, in breast milk using magnetic carbon nanotubes partially doped with nitrogen. Results: The calibration curves were linear in the range 5.0–180.0 ng ml-1. The limit of quantification was 5.0 ng ml-1. Coefficients of variation were between 3.2 and 13.9%. Recovery was between 89.6 and 99.2%. Conclusion: The proposed method is simple, efficient and suitable to determine analytes in breast milk.