Gas phase detection of chemical warfare agents CWAs with portable Raman

Marta Lafuente; Diego Sanz; Miguel Urbiztondo; Jesús Santamaría; María Pilar Pina; Reyes Mallada

doi:10.1016/j.jhazmat.2019.121279

Gas phase detection of chemical warfare agents CWAs with portable Raman

J Hazard Mater. 2020 Feb 15:384:121279. doi: 10.1016/j.jhazmat.2019.121279. Epub 2019 Sep 23.

Authors

Marta Lafuente¹, Diego Sanz¹, Miguel Urbiztondo², Jesús Santamaría³, María Pilar Pina³, Reyes Mallada⁴

Affiliations

¹ Nanoscience Institute of Aragon (INA), University of Zaragoza, Department of Chemical & Environmental Engineering, Edificio I+D+i, Campus Rio Ebro, C/Mariano Esquillor s/n, 50018, Zaragoza, Spain; Instituto de Ciencia de Materiales de Aragón (ICMA), Universidad de Zaragoza-CSIC, 50009, Zaragoza, Spain.
² Centro Universitario de la Defensa de Zaragoza, Carretera Huesca s/n, 50090, Zaragoza, Spain.
³ Nanoscience Institute of Aragon (INA), University of Zaragoza, Department of Chemical & Environmental Engineering, Edificio I+D+i, Campus Rio Ebro, C/Mariano Esquillor s/n, 50018, Zaragoza, Spain; Instituto de Ciencia de Materiales de Aragón (ICMA), Universidad de Zaragoza-CSIC, 50009, Zaragoza, Spain; Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN, 28029, Madrid, Spain.
⁴ Nanoscience Institute of Aragon (INA), University of Zaragoza, Department of Chemical & Environmental Engineering, Edificio I+D+i, Campus Rio Ebro, C/Mariano Esquillor s/n, 50018, Zaragoza, Spain; Instituto de Ciencia de Materiales de Aragón (ICMA), Universidad de Zaragoza-CSIC, 50009, Zaragoza, Spain; Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN, 28029, Madrid, Spain. Electronic address: rmallada@unizar.es.

PMID: 31606709
DOI: 10.1016/j.jhazmat.2019.121279

Abstract

The development of SERS substrates for chemical detection of specific analytes requires appropriate selection of plasmonic metal and the surface where it is deposited. Here we deposited Ag nanoplates on three substrates: i) conventional SiO₂/Si wafer, ii) stainless steel mesh and iii) graphite foils. The SERS enhancement of the signal was studied for Rhodamine 6 G (R6 G) as common liquid phase probe molecule. We conducted a comprehensive study with λ = 532, 633 and 785 nm on all the substrates. The best substrate was investigated, at the optimum laser 785 nm, for gas phase detection of dimethyl methyl phosphonate (DMMP), simulant of the G-series nerve agents, at a concentration of 2.5 ppmV (14 mg/m³). The spectral fingerprint was clearly observed; with variations on the relative intensities of SERS Raman bands compared to bulk DMMP in liquid phase reflects the DMMP-Ag interactions. These interactions were simulated by Density Functional Theory (DFT) calculations and the simulated spectra matched with the experimental one. Finally, we were detected the characteristics DMMP fingerprint with hand-held portable equipment. These results open the way for the application of SERS technique on real scenarios where robust, light-weight, miniaturized and simple to use and cost-effective tools are required by first responders.

Keywords: CWAs; Gas phase detection; Portable Raman; SERS; Trace level.

Publication types

Research Support, Non-U.S. Gov't