Defense Chemical Research Laboratory DCRL

Karaj, Iran

Defense Chemical Research Laboratory DCRL

Karaj, Iran

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Saeidian H.,Payame Noor University | Babri M.,Defense Chemical Research Laboratory DCRL | Mirjafary Z.,Islamic Azad University at Tehran | Naseri M.T.,Defense Chemical Research Laboratory DCRL | And 4 more authors.
International Journal of Mass Spectrometry | Year: 2014

The availability of mass spectra and interpretation skills are essential for unambiguous identification of the Chemical Weapons Convention (CWC)-related compounds. This paper examines electron ionization (EI) and electrospray ionization (ESI) mass spectral fragmentation routes of spiro alkylphosphonates I and 5,5-bis(chloromethyl)-2-alkyl-1,3,2-dioxaphosphinane 2-oxides II as compounds which are covered under CWC schedule 2.B.4. Mass spectrometric studies revealed some fragmentation pathways, such as elimination of alkyl(oxo)phosphane oxide (RPO2), chlorine, chloromethylene, alkene, HCl, and H2O, α-cleavage and McLafferty-type and hydrogen rearrangements. The proposed fragmentation processes include some new fragmentation patterns, such as isomerization of cations to stabilized carbocations and oxocarbocations, and elimination of formaldehyde and alkoxy through concerted retro [2 + 2] cycloaddition reaction and 1,2 PO alkyl shift. Structures of fragments were confirmed using EI-MS and MS/MS analysis of the deuterated analogs. The results will make a contribution to the Organization for the Prohibition of Chemical Weapons (OPCW) Central Analytical Database (OCAD) which may be used for the detection and identification of CWC-related compounds during on-site inspection and OPCW proficiency tests. © 2014 Elsevier B.V.


Naseri M.T.,Tarbiat Modares University | Naseri M.T.,Defense Chemical Research Laboratory DCRL | Shamsipur M.,Razi University | Babri M.,Defense Chemical Research Laboratory DCRL | And 4 more authors.
Analytical and Bioanalytical Chemistry | Year: 2014

The purpose of this study was to develop a sensitive and simple method, based on dispersive derivatization liquid-liquid microextraction-gas chromatography-mass spectrometry (DDLLME-GC-MS) in scanning and selected-ion-monitoring (SIM) modes, for detection of 2-chlorovinylarsonous acid (CVAA) as a hydrolysis product and urinary metabolite of lewisite in urine samples. Chloroform (65 μL), methanol (500 μL), and ethanedithiol (10 μL) were used as extraction solvent, dispersive solvent, and derivatizing reagent, respectively. Critical conditions of the proposed method were optimized. The nucleophilic reactions of dithiol and monothiol compounds with CVAA were also studied using a competitive method. In view of the high affinity of trivalent arsenic for sulfhydryl groups, the interaction between CVAA and bis(2-chlorovinyl)arsonous acid (BCVAA) and free cysteine (Cys) was also investigated using liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS). The interference of Cys, present in human urine, with the detection of CVAA was evaluated using dithiol and monothiol chemicals as derivatization agents. The developed method provided a preconcentration factor of 250, and limits of detection of 0.015 and 0.30 μg L-1 in SIM and scanning modes, respectively. The calibration curves were linear over the concentration range of 1-400 μg L-1 in full-scan mode. The relative standard deviation (RSD) values were calculated to be 5.5 and 3.2 % at concentrations of 20 and 100 μg L-1, respectively. Collision-induced dissociation studies of the major electron-impact (EI) ions were performed to confirm the proposed fragment structure of CVAA-dithiols derivatives. Results indicated that the developed method for analysis of CVAA is suitable not only for verification of human exposure to lewisite, but also for quantification of CVAA in urine samples. © 2014 Springer-Verlag Berlin Heidelberg.


Shamsipur M.,Razi University | Naseri M.T.,Tarbiat Modares University | Babri M.,Defense Chemical Research Laboratory DCRL
Journal of Pharmaceutical and Biomedical Analysis | Year: 2013

A simple, rapid and sensitive method based on dispersive derivatization liquid-liquid microextraction (DDLLME) combined with gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) was developed and validated for the determination of prostate cancer metabolite biomarkers, including sarcosine, alanine, leucine and proline, in human urine samples. Dispersive derivatization using isobutyl chloroformate has been successfully employed to identify the amino acids of interest in ngmL-1 concentrations. Under the optimum experimental conditions, the detection limits of the amino acids were in the range of 0.05-0.1ngmL-1. The enrichment factor and relative recovery for the target amino acids were in the range of 140-155 and 93.8-106%, respectively. The proposed method showed good linearity (correlation coefficients >0.997), and good intra-day (below 7%) and inter-day precision (below 10%). This protocol provides a rapid, simple, selective and sensitive tool to quantify sarcosine and endogenous urinary metabolite for prostate cancer diagnosis and for a screening test. © 2013 Elsevier B.V.


Saeidian H.,Payame Noor University | Sarabadani M.,Payame Noor University | Sarabadani M.,Defense Chemical Research Laboratory DCRL | Babri M.,Defense Chemical Research Laboratory DCRL
International Journal of Mass Spectrometry | Year: 2015

Mass spectrometric (MS) analytical features of phenoxide derivatives of sulfur and nitrogen mustards were described. Electron ionization (EI) mass spectra of title chemicals with possible fragmentation routes were investigated via analysis of fragment ions of deuterated analogs, MS-MS experiments and density functional theory calculations. EI-MS and EI-MS/MS analysis revealed phenoxide, ethane, CO, CS and H2S exclusions, α-cleavages, retro Diels-Alder cycloaddition, hydrogen rearrangements and a previously unknown intramolecular Claisen-type rearrangement. The results would be valuable during toxic chemical destruction monitoring in support of chemical weapons convention (CWC) and for the verification of state-parties activities, based on CWC context. © 2015 Elsevier B.V.


Saeidian H.,Payame Noor University | Babri M.,Defense Chemical Research Laboratory DCRL | Abdoli M.,Payame Noor University | Sarabadani M.,Defense Chemical Research Laboratory DCRL | And 2 more authors.
Rapid Communications in Mass Spectrometry | Year: 2012

RATIONALE The availability of mass spectra and interpretation skills are essential for unambiguous identification of the Chemical Weapons Convention (CWC)-related chemicals. The O(S)-alkyl N,N-dimethyl alkylphosphono(thiolo) thionoamidates are included in the list of scheduled CWC-related compounds, but there are very few spectra from these compounds in the literature. This paper examines these spectra and their mass spectral fragmentation routes. METHODS The title chemicals were prepared through microsynthetic protocols and were analyzed using electron ionization mass spectrometry with gas chromatography as a MS-inlet system. Structures of fragments were confirmed using analysis of fragment ions of deuterated analogs, tandem mass spectrometry and density functional theory (DFT) calculations. RESULTS Mass spectrometric studies revealed some interesting fragmentation pathways during the ionization process, such as alkene and amine elimination and McLafferty-type rearrangements. The most important fragmentation route of the chemicals is the thiono-thiolo rearrangement. DFT calculations are used to support MS results and to reveal relative preference formation of fragment ions. The retention indices (RIs) of all the studied compounds are also reported. CONCLUSIONS Mass spectra of the synthesized compounds were investigated with the aim to enrich the Organization for the Prohibition of Chemical Weapons (OPCW) Central Analytical Database (OCAD) which may be used for detection and identification of CWC-related chemicals during on-site inspection and/or off-site analysis such as OPCW proficiency tests. Copyright © 2012 John Wiley & Sons, Ltd.


Naseri M.T.,Defense Chemical Research Laboratory DCRL | Sarabadani M.,Defense Chemical Research Laboratory DCRL | Ashrafi D.,Defense Chemical Research Laboratory DCRL | Saeidian H.,Payame Noor University | Babri M.,Defense Chemical Research Laboratory DCRL
Environmental Science and Pollution Research | Year: 2013

The decomposition of highly toxic chemical warfare agent, sulfur mustard (bis(2-chloroethyl) sulfide or HD), has been studied by homogeneous photolysis and heterogeneous photocatalytic degradation on titania nanoparticles. Direct photolysis degradation of HD with irradiation system was investigated. The photocatalytic degradation of HD was investigated in the presence of TiO2 nanoparticles and polyoxometalates embedded in titania nanoparticles in liquid phase at room temperature (33 ± 2 °C). Degradation products during the treatment were identified by gas chromatography-mass spectrometry. Whereas apparent first-order kinetics of ultraviolet (UV) photolysis were slow (0. 0091 min-1), the highest degradation rate is obtained in the presence of TiO2 nanoparticles as nanophotocatalyst. Simultaneous photolysis and photocatalysis under the full UV radiation leads to HD complete destruction in 3 h. No degradation products observed in the presence of nanophotocatalyst without irradiation in 3 h. It was found that up to 90 % of agent was decomposed under of UV irradiation without TiO2, in 6 h. The decontamination mechanisms are often quite complex and multiple mechanisms can be operable such as hydrolysis, oxidation, and elimination. By simultaneously carrying out photolysis and photocatalysis in hexane, we have succeeded in achieving faster HD decontamination after 90 min with low catalyst loading. TiO2 nanoparticles proved to be a superior photocatalyst under UV irradiation for HD decontamination. © 2012 Springer-Verlag.


Saeidian H.,Payame Noor University | Babri M.,Defense Chemical Research Laboratory DCRL | Ramezani A.,Payame Noor University | Ashrafi D.,Defense Chemical Research Laboratory DCRL | And 2 more authors.
European Journal of Mass Spectrometry | Year: 2013

The electron ionization (EI) mass spectra of a series of O-alkyl O-2-(NN-dialkylamino)ethyl alkylphosphonites(phosphonates) which are precursors of nerve agents were studied for Chemical Weapons Convention (CWC) verification General EI fragmentation pathways were constructed and discussed Proposed fragment structures were confirmed through analyzing fragment ions of deuterated analogs and density functional theory (DFT) calculations The observed fragment ions are due to different fragmentation pathways such as hydrogen and McLafferty+1 rearrangements alkene amine and alkoxy elimination by α-or β-cleavage process Fragment ions distinctly allow unequivocal identification of the interested compounds including those of isomeric compounds The presence and abundance of fragment ions were found to depend on the size and structure of the alkyl group attached to nitrogen phosphorus and oxygen atoms © IM Publications LLP 2013.


Saeidian H.,Payame Noor University | Sarabadani M.,Payame Noor University | Sarabadani M.,Defense Chemical Research Laboratory DCRL
Journal of the Iranian Chemical Society | Year: 2015

Abstract Detection and identification of chemical warfare agents and their precursors/reaction products in various environmental matrices are important tasks which are considered in chemical weapons convention (CWC). 2-[(2-chloroethyl)(alkyl)amino]ethyl alkyl methylphosphonates I and N-alkyl bis(2-(alkoxy-methylphosphoryloxy)amines II are covered under schedule 2.B.4 of CWC and have structures closely related to the nerve and blister agents. In fact, they are products of the reactions between these two different CWC scheduled compounds: nerve agents and nitrogen mustards. Ion fragmentations during mass spectrometry studies of these chemicals were investigated using electron ionization mass spectrometry. Structures of fragments were confirmed using EI-MS analysis of the deuterated analogs. Density functional theory was also used to show preferred fragmentation pathways. Mass spectrometric studies revealed some fragmentation pathways, such as, McLafferty-type and hydrogen rearrangements and elimination of chlorine, chloromethylene radical, alkene and HCl. © Iranian Chemical Society 2014.


Saeidian H.,Payame Noor University | Babri M.,Defense Chemical Research Laboratory DCRL | Ashrafi D.,Defense Chemical Research Laboratory DCRL | Sarabadani M.,Defense Chemical Research Laboratory DCRL | Naseri M.T.,Defense Chemical Research Laboratory DCRL
Analytical and Bioanalytical Chemistry | Year: 2013

The electron-impact (EI) mass spectra of a series of O-alkyl methylphosphonothionocyanidates were studied for Chemical Weapons Convention (CWC) purposes. General EI fragmentation pathways were constructed and discussed, and collision-induced dissociation studies of the major EI ions were performed to confirm proposed fragment structures by analyzing fragment ions of deuterated analogs and by use of density functional theory (DFT) calculations. Thiono-thiolo rearrangement, McLafferty-type rearrangement, and a previously unknown intramolecular electrophilic aromatic substitution reaction were observed and confirmed. The study also focused on differentiation of isomeric compounds. Retention indices for all compounds, and an electrophilicity index for several compounds, are reported and interpreted. © 2013 Springer-Verlag Berlin Heidelberg.


Saeidian H.,Payame Noor University | Ashrafi D.,Defense Chemical Research Laboratory DCRL | Sarabadani M.,Defense Chemical Research Laboratory DCRL | Naseri M.T.,Defense Chemical Research Laboratory DCRL | Babri M.,Defense Chemical Research Laboratory DCRL
International Journal of Mass Spectrometry | Year: 2012

Modified microsynthesis of O(S)-alkyl N,N-dimethylamino alkylphosphonates (alkylphosphonothiolates) which are included in schedule 2 of Chemical Weapons Convention (CWC) annex of chemicals, is reported. Retention indices and electron ionization mass spectral data with fragmentation routes for these chemicals are also given. Mass spectrometric studies revealed that their fragmentations were dominated by alkene elimination, McLafferty rearrangement, α-cleavage, amine elimination, etc. Conclusions were confirmed using MS/MS experiments, fragment ions of deuterated analogs and density functional theory calculations. © 2012 Elsevier B.V. All rights reserved.

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