Analysis of chemical warfare agents by portable Raman spectrometer with both 785nm and 1064nm excitation.

The Raman spectra of twenty-two chemical warfare agents (CWAs) were measured: eleven nerve agents and their precursor, five blister agents, three lachrymators, one choking agent, and one vomit agent, in liquid or solid state in colorless transparent vials were analyzed using a portable Raman spectrometer, Xantus-2 from Rigaku Corporation, equipped with selectable excitation lasers (785nm and 1064nm). With 785nm excitation, characteristic Raman spectra composed of many sharp peaks were observed for twenty CWAs, but nitrogen mustard 3 (HN3) and adamsite (DM) did not show particular peaks owing to broad and intense mountain-like baselines. With 1064nm excitation, Raman spectra similar to those with 785nm excitation were observed for the twenty CWAs, where the wavenumbers of the peak tops and comparative heights were similar to those with 785nm excitation.

Real-time air monitoring of mustard gas and Lewisite 1 by detecting their in-line reaction products by atmospheric pressure chemical ionization ion trap tandem mass spectrometry with counterflow ion introduction.

A new method enabling sensitive real-time air monitoring of highly reactive chemical warfare agents, namely, mustard gas (HD) and Lewisite 1 (L1), by detecting ions of their in-line reaction products instead of intact agents, is proposed. The method is based on corona discharge-initiated atmospheric pressure chemical ionization coupled with ion trap tandem mass spectrometry (MS(n)) via counterflow ion introduction. Therefore, it allows for highly sensitive and specific real-time detection of a broad range of airborne compounds.

Sensitive and comprehensive detection of chemical warfare agents in air by atmospheric pressure chemical ionization ion trap tandem mass spectrometry with counterflow introduction.

A highly sensitive and specific real-time field-deployable detection technology, based on counterflow air introduction atmospheric pressure chemical ionization, has been developed for a wide range of chemical warfare agents (CWAs) comprising gaseous (two blood agents, three choking agents), volatile (six nerve gases and one precursor agent, five blister agents), and nonvolatile (three lachrymators, three vomiting agents) agents in air. The approach can afford effective chemical ionization, in both positive and negative ion modes, for ion trap multiple-stage mass spectrometry (MS(n)). The volatile and nonvolatile CWAs tested provided characteristic ions, which were fragmented into MS(3) product ions in positive and negative ion modes.

Sensitive monitoring of volatile chemical warfare agents in air by atmospheric pressure chemical ionization mass spectrometry with counter-flow introduction.

A new method for sensitively and selectively detecting chemical warfare agents (CWAs) in air was developed using counter-flow introduction atmospheric pressure chemical ionization mass spectrometry (MS). Four volatile and highly toxic CWAs were examined, including the nerve gases sarin and tabun, and the blister agents mustard gas (HD) and Lewisite 1 (L1). Soft ionization was performed using corona discharge to form reactant ions, and the ions were sent in the direction opposite to the airflow by an electric field to eliminate the interfering neutral molecules such as ozone and nitrogen oxide.