Electrospray ionization mass spectral studies of N,N‐dialkylaminoethane‐2‐sulphonic acids

Abstract

Oxidative reactions of VX type compounds and N,N-dialkylaminoethane-2-thiols that are precursors for VX compounds produce N,N-dialkylaminoethane-2-sulphonic acids, N(R(1))(R(2))-CH(2)-CH(2)SO(3)H (where R(1) and R(2) = methyl, ethyl, n-propyl and isopropyl, 1-10), as the degradation products, and these degradation products are considered as markers for the detection of chemicals listed in the schedules of Chemical Weapons Convention (CWC) chemicals. Off-site detection of such degradation products in aqueous samples is an important task in the verification of CWC-related chemicals. Here we report a simple method involving the direct analysis of aqueous samples using positive and/or negative ion electrospray ionization (ESI) for the screening, detection and identification of N,N-dialkylaminoethane-2-sulphonic acids, avoiding sample preparation and chromatographic steps. The positive ion ESI mass spectra of all the compounds result in abundant [M+Na](+) ions, and the negative ion spectra show abundant [M-H](-) ions to confirm their molecular weight. The collision-induced dissociation spectra of [M+Na](+) and [M-H](-) give characteristic product ions by which it is easy to detect and identify all the studied N,N-dialkylaminoethane-2-sulphonic acids including those of isomeric compounds. The method is successfully applied to detect the spiked chemical, N,N-diisopropylaminoethane-2-sulphonic acid, present in a water sample received in a proficiency test.

Mass spectral analysis of N‐oxides of Chemical Weapons Convention related aminoethanols under electrospray ionization conditions

“…Their detection in suspect matrices confirms the presence of either of these two classes of toxic chemicals. Sample preparation, detection and identification methods have been established for aminoethanethiols, aminoethanechlorides, aminoethanols, and aminoethylsulfonic acids (degradation product) 9–17. These compounds are expected to undergo N‐oxidation during the decontamination process or upon aerial oxidation 18, 19.…”

Mass spectrometric study on O(S)-alkyl N,N-dimethylamino alkylphosphonates (alkylphosphonothiolates) for Chemical Weapons Convention verification purposes

“…mass spectra of the CW agents, their precursors and degradation products such as N,N-dialkylaminoethanols, alkylphosphonates, N,N-dialkylphosphoramidates, sulfur and nitrogen mustard, methylphosphonites, N,N-dialkylaminoethane-2-sulfonic acids, Noxides of aminoethanols, N,N-dialkylaminoethane-2-thiols, alkyl methylphosphoric acids [4][5][6][7][8][9][10][11][12][13][14]. One of the CWC-related chemicals is O(S)-alkyl N,N-dimethylamino alkylphosphonates (alkylphosphonothiolates).…”

Mass Spectrometry in India

“…The group also developed solid-phase extraction (SPE) and ion-pair SPE methods for the analysis of nonpolar and polar CWC-related chemicals. [123][124][125][126][127][128][129][130][131][132][133] The Vertox Laboratory, Defense Research and Development Establishment, Gwalior, is another laboratory in India formally designated for the off-site analysis of chemicals prohibited under the CWC. [134][135][136][137][138][139][140][141][142][143] Work by Dubey and colleagues within this laboratory is devoted to developing novel extraction, derivatization and analytical methods for the analysis of scheduled chemicals, related degradation products and their derivatives in various matrices.…”