Shimeng Duan,Haiou Chen,Anyun Xu,Ying He,Meng Li,Ru Zhang,Ruilin Zhang,Huiping Bai
In this study, a simple electrochemical sensor based on l -arginine membrane (P-L-arg/GCE) was developed for rapid and sensitive detection of MDMA and MDA. A polyarginine membrane was obtained through one-step direct electropolymerization, which provides more reaction sites for the analyte and improves the sensitivity of the sensor. Following the optimized selection parameters, the MDMA detection range was established at 1.0 × 10 −7 ∼3.5 × 10 −5 mol L −1 , with a detection limit of 3.3 × 10 −8 mol L −1 . Similarly, the detection range for MDA was established at 1.0 × 10 −7 ∼5.3 × 10 −5 mol L −1 with a detection limit of 3.3 × 10 −8 mol L −1 . Additionally, the potential oxidation mechanism of MDMA and MDA during the REDOX process was analyzed by cyclic voltammetry . Furthermore, the proposed sensor exhibited superior selectivity, excellent reproducibility, and satisfactory stability. The proposed sensors can be used for reliable monitoring of MDMA or MDA in human urine and hair samples, respectively, and it has acceptable analytical reliability and enormous potential for practical applications.
Recently a new type of mixed drug oral solution has become prevalent in China, the identification and quantitative inspection of which are demanded in conviction and sentencing as well as drug intelligence. In 2013, inspection was carried out on 86 bottles of substances seized in 13 cases with the adoption of GC–MS methodology for qualitative identification and GC–FID for quantitative identification. 94.1% of the samples were light yellow turbid liquid while 95.3% were detected with more than two drugs. Detection rate of methamphetamine, MDMA and ketamine was up to 89.5%, 37.2% and 83.7% respectively. Quantitative inspection results indicated that concentrations of methamphetamine, MDMA , ketamine were 0.04–13 mg/mL, 0.04–29 mg/mL and 0.1–34 mg/mL, respectively. Appearance, composition and drug concentration of samples vary from case to case.
A sensitive and novel method for the determination of methamphetamine (MAMP), 3,4-methylenedioxymethamphetamine (MDMA) and their metabolites amphetamine (AMP), 3,4-methylenedioxyamphetamine (MDA) in human hair was established by the employment of flash evaporation-gas chromatography/mass spectrometry (FE-GC/MS) combined with micro-reaction device. 0.30 mg human hair after cutting was put into a sealed glass capillary and heated at 270 °C in a pyrolyzer for 0.5 min. MAMP, AMP, MDMA and MDA evaporated from the hair were converted into their corresponding trifluoroacetylation product in a 60 °C water bath for 30 min with the acetylation by 2 μL trifluoroacetic anhydride (TFAH). Thus, amphetamines (AMPs) in human hair were separated and detected by GC/MS in SIM mode. The obtained calibration curves showed good linearity with the concentrations of MAMP, MDMA and MDA at 1–100 ng/mg, and AMP at 2–100 ng/mg. The linear correlation coefficients (r) were all larger than 0.996. Limits of detection for MAMP, AMP, MDMA and MDA were 0.67, 0.07, 0.17 and 0.07 ng/mg respectively. Limits of quantification for MAMP, AMP, MDMA and MDA were 2.00, 0.20, 0.50 and 0.20 ng/mg respectively. The precision over a range of 0.63–9.98 % were obtained with the recoveries of 92.7–115.2 % for AMPs. Five positive hair samples, three suspicious hair samples and two negative hair samples were successfully analyzed. The results of FE-GC/MS with micro-reaction device were comparable with those found by the referenced method. It was demonstrated that the developed method had potential applications for the analysis of AMPs in hair.
危险品化学品经营许可证（带存储）