Determination of hydrazine, monomethylhydrazine, 1,1‐dimethylhydrazine, and 1,2‐dimethylhydrazine by nonaqueous capillary electrophoresis with amperometric detection

Abstract

The present study is concerned with the application of nonaqueous capillary electrophoresis (NACE) with electrochemical detection (ED) to the separation and quantitative determination of hydrazine (Hy) and its methyl derivatives. The best performance of NACE-ED was found when using 4 mM sodium acetate/10 mM acetic acid/methanol: acetonitrile = 1:2 as the running buffer, with a bare platinum working electrode set at +1.0 V in an end-column amperometric detection cell. The choice and ratio of suitable solvents for the separation and injection media played an essential role for the performance characteristics of the method. The limits of detection for Hy, methylhydrazine, symmetrical dimethylhydrazine, and unsymmetrical dimethylhydrazine were 5, 2, 12, and 1 ng/mL, respectively. This is between one and two orders of magnitude lower than that achieved by previously reported CE-ED methods in aqueous buffer systems in conjunction with various types of chemically modified electrodes. The practical utility of the new NACE-ED methodology is demonstrated in terms of the determination of traces of Hys in spiked environmental samples containing a wide range of explosives and related compounds.

Capillary electrophoresis and microchip capillary electrophoresis with electrochemical and electrochemiluminescence detection

“…An off-line SPE procedure was utilized to extract and preconcentrate the pollutants prior to separation and detection, with ENVIChrom P, a highly cross-linked styrene-divinylbenzene copolymer, being employed as the sorbent. Matysik et al [58] described non-aqueous capillary electrophoresis with AD as a selective and sensitive separation and quantitative determination of hydrazine and its methyl derivatives. The choice and ratio of suitable solvents for the separation and injection media played an essential role for the performance characteristics of the method.…”

Electrochemical and optical detectors for capillary and chip separations

“…By proper choice and ratio of suitable non-aqueous solvents, Matysik [2] was able to achieve LODs of hydrazine and its methyl derivatives one to two orders of magnitude lower than that achieved by CE-EC methods in aqueous buffer systems in conjunction with various types of chemicallymodified electrodes.…”

“…The typical diameters for the electrodes are several hundred micrometers, while the separation-capillary inner diameters are in the tens-of-micrometer range. This detection set-up has been successfully used in environmental analysis [1,2] and herbal medicine [3][4][5][6][7][8][9], and for biological samples [10].…”

Recent advances in the applications of CE to forensic sciences (2005–2007)

“…The determination of hydrazine, monomethylhydrazine, 1,1-dimethylhydrazine and 1,2 dimethylhydrazine in environmental samples was reported by Guo et al [54]. The method used nonaqueous CE in 4 mM sodium acetate/10 mM acetic acid/methanol:ACN (1:2) as the running buffer with amperometric detection with a bare platinum working electrode set at 1.0 V at the end of the column.…”