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ABSTRACT: The influence of eluent composition (the nature and concentration of the ion-pair reagent, medium pH, the concentration of
the buffer solution, and the content of acetonitrile) on the retention of asymmetric dimethylhydrazine and its decomposition
products on hydrophobized silica gels under the ion pair chromatography conditions was studied. It was shown that, for these
sorbates, the influence of ion-pair reagents can be described correctly in terms of stoichiometric models. Empirical dependences
of the retention of the components studied on the concentration of the buffer solution and the volume concentration of acetonitrile
were determined. Conditions for the separation of the components were suggested.
Russian Journal of Physical Chemistry 04/2012; 83(3):478-487. · 0.46 Impact Factor
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ABSTRACT: Procedures are developed on the basis of liquid chromatography/mass spectrometry for determining the transformation products
of unsymmetrical dimethylhydrazine in soils: formic acid dimethylhydrazide (1-formyl-2,2-dimethylhydrazine, analytical range
0.01–20 mg/kg), 1-methyl-1,2,4-triazole (analytical range 0.05–100 mg/kg), 1,1-dimethylguanidine (analytical range 0.05–100
mg/kg), and dimethylamine (analytical range 0.25–250 mg/kg). The measurements were performed in the mode of chemical ionization
under atmospheric pressure followed by the registration of positive ions corresponding to the protonated forms of the components
to be determined. A version of ion chromatography was elaborated for separation. For sample pretreatment, the use of extraction
with methanol (for 1-formyl-2,2-dimethylhydrazine) and ultrasonic extraction with a weakly alkaline buffer solution (for other
substances) was proposed.
Keywordsliquid chromatography/mass spectrometry-quantitative analysis-ecotoxicants-unsymmetrical dimethylhydrazine
Journal of Analytical Chemistry 04/2012; 65(13):1405-1410. · 0.75 Impact Factor
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ABSTRACT: The influence of the nature of the ion-pair reagent (IPR) using sodium octylsulfate, octylsulfonate, and dodecylsulfate as
an example on the separation of asymmetric dimethylhydrazine (ADMH) and its decomposition products has been investigated using
a Synergi Hydro RP column. It has been shown that the use of sodium octylsulfate as an IRP is preferable. The approach to
simultaneous determination of hydrazine, methylhydrazine, ADMH, N-nitrosodimethylamine, and tetramethyl-2-tetrazene with detection
limits in water matrices of 0.3, 0.7, 0.8, 7, and 1.2 μg/L respectively (sample volume of 100 μL) has been proposed.
Moscow University Chemistry Bulletin 04/2012; 64(3):147-153.
