Gas Chromatography–Mass Spectrometry Quantification of 1,1-Dimethylhydrazine Transformation Products in Aqueous Solutions: Accelerated Water Sample Preparation
Abstract
:1. Introduction
2. Results and Discussion
2.1. Extraction Efficiency and Optimization
2.2. Analytical Method and Its Validation
2.3. Analyses of Real Samples
3. Materials and Methods
3.1. Analytes, Reagents and Materials
3.2. Real Objects
- Sample 1. River water (Northern Dvina River) with a salinity of 140 mg L−1 and a dissolved organic carbon content of 13 mg L−1.
- Sample 2. Water extract of peat bog soil, typical for landing places of launch vehicle’s spent stages in the European North of Russia. A soil sample weighing 1 g was placed in a 20 mL glass vial and poured with 10 mL of deionized water, then suspended with continuous vigorous stirring on a vortex (1500 rpm) for 20 min. After settling for two days and centrifugation the aqueous solution was separated and stored at 4 °C for no more than one week.
- Sample 3. An aqueous solution of 1,1-dimethylhydrazine with an initial concentration of 7000 mg L−1, which was in contact with air for 4 years and thus underwent significant oxidative conversion. The solution was yellow in color.
- Sample 4. An aqueous solution of 1,1-dimethylhydrazine with an initial concentration of 1000 mg L−1 subjected to pyrolytic gasification in supercritical water for 2 h at 600 °C [27]. This sample represents a product of detoxification of rocket fuel containing wastewater.
3.3. AWASP Procedure
3.4. GC-MS (MS/MS) Analyses
No | Analyte | tR, min | SIM | MRM | ||||
---|---|---|---|---|---|---|---|---|
Quantifier ion, m/z | Qualifier ion m/z | Quantifier | Qualifier | |||||
m/z | CE, eV | m/z | CE, eV | |||||
1 | TMT | 5.91 | 116 | 72 | 116→72 | 6 | 72→44 | 3 |
2 | Pyridine | 7.00 | 79 | 52 | 79→52 | 15 | 52→50 | 9 |
3 | Pyrazine | 7.54 | 80 | 53 | 80→53 | 12 | 80→51 | 39 |
4 | 2-Methylpyridine | 7.75 | 93 | 66 | 93→66 | 15 | 93→78 | 18 |
5 | DMAAN | 8.04 | 84 | 58 | 83→42 | 6 | 84→57 | 6 |
6 | 2,6-Dimethylpyridine | 8.18 | 107 | 66 | 107→65 | 21 | 107→92 | 18 |
7 | 1-Methyl-1H-pyrazole | 8.21 | 82 | 54 | 82→54 | 18 | 82→42 | 21 |
8 | 2-Methylpyrazine | 8.50 | 94 | 67 | 94→67 | 12 | 67→40 | 6 |
9 | 3-Methylpyridine | 9.00 | 93 | 66 | 93→66 | 15 | 93→39 | 36 |
10 | 4-Methylpyridine | 9.38 | 93 | 66 | 93→66 | 15 | 93→39 | 36 |
11 | NDMA | 9.51 | 74 | 42 | 74→44 | 6 | 74→42 | 21 |
12 | 2,5-Dimethylpyrazine | 9.48 | 108 | 42 | 108→42 | 18 | 108→81 | 9 |
13 | 2,6-Dimethylpyrazine | 9.77 | 108 | 42 | 108→42 | 18 | 108→40 | 18 |
14 | DMF | 9.82 | 73 | 44 | 73→44 | 6 | 73→58 | 6 |
15 | 2,3-Dimethylpyrazine | 9.77 | 108 | 67 | 108→67 | 12 | 67→40 | 6 |
16 | 2,4,6-Trimethylpyridine | 10.10 | 121 | 79 | 121→79 | 15 | 79→77 | 12 |
17 | 3,5-Dimethylpyridine | 10.78 | 107 | 79 | 107→92 | 15 | 106→77 | 15 |
18 | 2,3,5-Trimethylpyridine | 11.70 | 121 | 106 | 121→77 | 33 | 120→77 | 18 |
19 | 1-Methyl-1H-1,2,4-triazole | 13.18 | 83 | 56 | 83→56 | 6 | 83→55 | 18 |
20 | FADMH | 14.06 | 59 | 43 | 59→44 | 9 | 59→43 | 15 |
21 | 1-Methyl-1H-imidazole | 14.44 | 82 | 54 | 82→55 | 12 | 82→42 | 18 |
22 | 1H-pyrazole | 15.96 | 68 | 41 | 68→41 | 15 | 67→40 | 12 |
23 | 3-Methyl-1H-pyrazole | 16.35 | 81 | 82 | 82→54 | 18 | 81→54 | 6 |
24 | 3,5-Dimethyl-1H-pyrazole | 16.80 | 95 | 96 | 95→41 | 15 | 95→68 | 6 |
25 | 2,4-Dimethyl-1H-imidazole | 17.49 | 96 | 95 | 95→41 | 18 | 95→68 | 6 |
26 | 4-Methyl-1H-pyrazole | 16.93 | 82 | 81 | 82→55 | 12 | 81→54 | 6 |
27 | 3,4-Dimethyl-1H-pyrazole | 19.87 | 95 | 96 | 96→54 | 21 | 95→68 | 6 |
28 | 1H-imidazole | 20.30 | 68 | 55 | 68→41 | 15 | 67→40 | 6 |
29 | 4-Methyl-1H-imidazole | 20.42 | 82 | 81 | 82→54 | 18 | 81→54 | 6 |
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
Sample Availability
References
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No | Analyte | SIM | MRM | Linear Range | ||||||
---|---|---|---|---|---|---|---|---|---|---|
a | r2 | LOD | LOQ | a | r2 | LOD | LOQ | |||
1 | TMT | 0.477 | 0.999 | 3.1 | 10 | 0.215 | 0.999 | 4.7 | 16 | LOQ–50 |
2 | Pyridine | 0.854 | 0.999 | 2.1 | 7.0 | 0.840 | 0.999 | 0.7 | 2.4 | LOQ–58 |
3 | Pyrazine | 0.721 | 0.999 | 2.0 | 6.5 | 0.461 | 0.999 | 2.7 | 9.1 | LOQ–58 |
4 | 2-methyl-Pyridine | 0.963 | 0.999 | 2.1 | 7.1 | 0.373 | 0.999 | 3.2 | 11 | LOQ–71 |
5 | DMAAN | 0.359 | 0.999 | 26 | 88 | 0.227 | 0.999 | 3.7 | 12 | LOQ–54 |
6 | 2,6-Dimethylpyridine | 1.16 | 0.999 | 1.0 | 3.2 | 0.273 | 0.999 | 2.4 | 8.1 | LOQ–56 |
7 | 1-Methyl-1H-Pyrazole | 0.865 | 0.999 | 2.3 | 7.7 | 0.198 | 0.999 | 2.5 | 8.2 | LOQ–58 |
8 | 2-Methylpyrazine | 0.898 | 0.999 | 2.1 | 6.9 | 0.503 | 0.999 | 1.9 | 6.4 | LOQ–59 |
9 | 3-methylpyridine | 0.905 | 0.999 | 3.2 | 11 | 0.344 | 0.999 | 4.7 | 15 | LOQ–58 |
10 | 4-methylpyridine | 0.980 | 0.999 | 3.1 | 10 | 0.427 | 0.999 | 4.0 | 13 | LOQ–60 |
11 | NDMA | 0.507 | 0.999 | 4.6 | 15 | 0.307 | 0.999 | 4.8 | 16 | LOQ–50 |
12 | 2,5-Dimethylpyrazine | 0.910 | 0.999 | 2.0 | 6.8 | 0.274 | 0.999 | 2.0 | 6.5 | LOQ–57 |
13 | 2,6-Dimethylpyrazine | 1.21 | 0.999 | 1.5 | 5.1 | 0.285 | 0.999 | 1.9 | 6.4 | LOQ–53 |
14 | DMF | 0.496 | 0.999 | 5.5 | 18 | 0.242 | 0.999 | 3.0 | 9.9 | LOQ–57 |
15 | 2,3-Dimethylpyrazine | 0.904 | 0.999 | 1.9 | 6.2 | 0.568 | 0.999 | 1.2 | 4.0 | LOQ–60 |
16 | 2,4,6-Trimethylpyridine | 1.38 | 0.999 | 1.0 | 3.2 | 0.352 | 0.999 | 1.3 | 4.4 | LOQ–55 |
17 | 3,5-Dimethylpyridine | 1.08 | 0.999 | 1.2 | 4.0 | 0.243 | 0.999 | 2.9 | 9.8 | LOQ–57 |
18 | 2,3,5-Trimethylpyridine | 1.13 | 0.999 | 1.2 | 3.8 | 0.160 | 0.999 | 2.0 | 6.7 | LOQ–54 |
19 | 1-Methyl-1H-1,2,4-triazole | 0.432 | 0.999 | 5.7 | 19 | 0.492 | 0.998 | 2.1 | 7.2 | LOQ–63 |
20 | FADMH | 0.136 | 0.995 | 16 | 54 | 0.095 | 0.994 | 17 | 56 | LOQ–59 |
21 | 1-Methyl-1H-imidazole | 0.765 | 0.998 | 3.3 | 11 | 0.285 | 0.998 | 2.1 | 7.1 | LOQ–63 |
22 | 1H-pyrazole | 0.500 | 0.998 | 3.3 | 11 | 0.257 | 0.999 | 6.3 | 20 | LOQ–57 |
23 | 3-Methyl-1H-pyrazole | 0.411 | 0.999 | 5.0 | 17 | 0.127 | 0.999 | 2.8 | 9.4 | LOQ–59 |
24 | 3,5-Dimethyl-1H-pyrazole | 0.650 | 0.999 | 3.9 | 13 | 0.143 | 0.999 | 4.6 | 15 | LOQ–58 |
25 | 2,4-Dimethyl-1H-imidazole | 0.640 | 0.999 | 4.0 | 13 | 0.136 | 0.999 | 4.1 | 13 | LOQ–58 |
26 | 4-Methyl-1H-pyrazole | 0.490 | 0.999 | 4.1 | 14 | 0.146 | 0.999 | 4.4 | 15 | LOQ–54 |
27 | 3,4-Dimethyl-1H-pyrazole | 0.158 | 0.991 | 21 | 68 | 0.120 | 0.990 | 10 | 33 | LOQ–56 |
28 | 1H-imidazole | 0.225 | 0.991 | 21 | 71 | 0.302 | 0.992 | 37 | 120 | LOQ–58 |
29 | 4-methyl-1H-Imidazole | 0.300 | 0.973 | 11 | 36 | 0.153 | 0.980 | 26 | 87 | LOQ–56 |
No | Analyte | RSD, % | |
---|---|---|---|
Intra-Day | Inter-Day | ||
1 | TMT | 5 | 6 |
2 | Pyridine | 5 | 8 |
3 | Pyrazine | 6 | 8 |
4 | 2-Methylpyridine | 7 | 11 |
5 | DMAAN | 8 | 10 |
6 | 2,6-Dimethylpyridine | 8 | 9 |
7 | 1-Methyl-1H-pyrazole | 6 | 7 |
8 | 2-Methylpyrazine | 8 | 10 |
9 | 3-Methylpyridine | 5 | 11 |
10 | 4-Methylpyridine | 5 | 10 |
11 | NDMA | 4 | 8 |
12 | 2,5-Dimethylpyrazine | 4 | 8 |
13 | 2,6-Dimethylpyrazine | 4 | 8 |
14 | DMF | 4 | 6 |
15 | 2,3-Dimethylpyrazine | 5 | 11 |
16 | 2,4,6-Trimethylpyridine | 6 | 13 |
17 | 3,5-Dimethylpyridine | 5 | 10 |
18 | 2,3,5-Trimethylpyridine | 7 | 9 |
19 | 1-Methyl-1H-1,2,4-triazole | 8 | 11 |
20 | FADMH | 10 | 15 |
21 | 1-Methyl-1H-imidazole | 8 | 12 |
22 | 1H-pyrazole | 5 | 9 |
23 | 3-Methyl-1H-pyrazole | 6 | 8 |
24 | 3,5-Dimethyl-H-pyrazole | 4 | 9 |
25 | 2,4-Dimethyl-1H-imidazole | 8 | 10 |
26 | 4-Methyl-1H-pyrazole | 6 | 10 |
27 | 3,4-Dimethyl-1H-pyrazole | 5 | 10 |
28 | 1H-imidazole | 8 | 13 |
29 | 4-Methyl-1H-imidazole | 10 | 15 |
No | Analyte | Concentration, µg L−1 | |
---|---|---|---|
Sample 3 | Sample 4 | ||
1 | TMT | n.d.* | 19 ± 1 |
2 | Pyridine | 3.2 ± 0.8 | 403 ± 27 |
3 | Pyrazine | 5.4 ± 0.1 | 31 ± 2 |
4 | 2-Methylpyridine | n.d. | 125 ± 14 |
5 | DMAAN | n.d. | n.d. |
6 | 2,6-Dimethylpyridine | n.d. | 7.4 ± 1.9 |
7 | 1-Methyl-1H-pyrazole | 95 ± 9 | 2180 ± 120 |
8 | 2-Methylpyrazine | 5.9 ± 0.2 | 122 ± 5 |
9 | 3-Methylpyridine | n.d. | 274 ± 21 |
10 | 4-Methylpyridine | n.d. | 11 ± 1 |
11 | NDMA | 31,200 ± 1800 | 3590 ± 140 |
12 | 2,5-Dimethylpyrazine | n.d. | 4.5 ± 0.2 |
13 | 2,6-Dimethylpyrazine | n.d. | 15 ± 1 |
14 | DMF | 220 ± 50 | 5920 ± 200 |
15 | 2,3-Dimethylpyrazine | n.d. | 8.0 ± 1.0 |
16 | 2,4,6-Trimethylpyridine | n.d. | 3.4 ± 1.1 |
17 | 3,5-Dimethylpyridine | n.d. | 9.7 ± 1.4 |
18 | 2,3,5-Trimethylpyridine | n.d. | 5.2 ± 1.9 |
19 | 1-Methyl-1H-1,2,4-triazole | 48,700 ± 7400 | 10,500 ± 220 |
20 | FADMH | n.d. | 25,100 ± 2100 |
21 | 1-Methyl-1H-imidazole | n.d. | 430 ± 35 |
22 | 1H-pyrazole | 25 ± 7 | 30 ± 3 |
23 | 3-Methyl-1H-pyrazole | n.d. | 8.8 ± 3.7 |
24 | 3,5-Dimethyl-1H-pyrazole | n.d. | n.d. |
25 | 2,4-Dimethyl-1H-imidazole | n.d. | n.d. |
26 | 4-Methyl-1H-pyrazole | n.d. | n.d. |
27 | 3,4-Dimethyl-1H-pyrazole | n.d. | n.d. |
28 | 1H-imidazole | n.d. | n.d. |
29 | 4-Methyl-1H-imidazole | n.d. | n.d. |
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Popov, M.S.; Ul’yanovskii, N.V.; Kosyakov, D.S. Gas Chromatography–Mass Spectrometry Quantification of 1,1-Dimethylhydrazine Transformation Products in Aqueous Solutions: Accelerated Water Sample Preparation. Molecules 2021, 26, 5743. https://doi.org/10.3390/molecules26195743
Popov MS, Ul’yanovskii NV, Kosyakov DS. Gas Chromatography–Mass Spectrometry Quantification of 1,1-Dimethylhydrazine Transformation Products in Aqueous Solutions: Accelerated Water Sample Preparation. Molecules. 2021; 26(19):5743. https://doi.org/10.3390/molecules26195743
Chicago/Turabian StylePopov, Mark S., Nikolay V. Ul’yanovskii, and Dmitry S. Kosyakov. 2021. "Gas Chromatography–Mass Spectrometry Quantification of 1,1-Dimethylhydrazine Transformation Products in Aqueous Solutions: Accelerated Water Sample Preparation" Molecules 26, no. 19: 5743. https://doi.org/10.3390/molecules26195743