Determination of transformation products of unsymmetrical dimethylhydrazine in water using vacuum-assisted headspace solid-phase microextraction

作者：Orazbayeva Dina; Kenessov Bulat^*; Psillakis Elefteria; Nassyrova Dayana; Bektassov Marat

来源：Journal of Chromatography A, 2018, 1555: 30-36.

DOI：10.1016/j.chroma.2018.04.048

• Headspace solid-phase microextraction
• Vacuum-assisted headspace solid-phase microextraction
• Multiple headspace solid-phase microextraction
• Transformation products
• Dimethylhydrazine
• Water analysis

A new, sensitive and simple method based on vacuum-assisted headspace solid-phase microextracdon (Vac-HSSPME) followed by gas chromatography-mass-spectrometry (GC-MS), is proposed for the quantification of rocket fuel unsymmetrical dimethylhydrazine (UDMH) transformation products in water samples. The target transformation products were: pyrazine, 1-methyl-1H-pyrazole, N-nitrosodimethylamine, N,N-dimethylformamide, 1-methyl-1H-1,2,4-triazole, 1-methyl-imidazole and 1H-pyrazole. For these analytes and within shorter sampling times, Vac-HSSPME yielded detection limits (0.5-100 ng L-1) 3-10 times lower than those reported for regular HSSPME. Vac-HSSPME sampling for 30 min at 50 degrees C yielded the best combination of analyte responses and their standard deviations (<15%). 1-Formyl-2,2-dimethylhydrazine and formamide were discarded because of the poor precision and accuracy when using Vac-HSSPME. The recoveries for the rest of the analytes ranged between 80 and 119%. The modified Mininert valve and Thermogreen septum could be used for automated extraction as it ensured stable analyte signals even after long waiting times (>24 h). Finally, multiple Vac-HSSME proved to be an efficient tool for controlling the matrix effect and quantifying UDMH transformation products.

• 出版日期2018-6-22