Non-gas-phase AgF-mediated conversion combined with vapour sampling for field analysis of V-agents and selected...

Rapid and reliable field identification of persistent chemical warfare agents remains a major challenge for CBRN responders. The low volatility and strong surface adsorption of V-type nerve agents severely limit the effectiveness of vapour-based detection techniques such as portable GC/MS systems. To address this, a wipe-then-cleave method based on AgF-mediated conversion was developed and validated for field analysis of V-agents and selected organophosphorus pesticides. The approach enables direct AgF cleavage of the collected analyte on the sampling swab, generating volatile fluoridate products suitable for gas-phase detection without prior extraction or sample preparation. The reaction proceeds rapidly under ambient conditions, allowing analysis within minutes. The method was evaluated using a HAPSITE® Smart PLUS portable GC/MS across representative interior materials. Two operational modes were established: a high-sensitivity mode for trace detection and a high-load mode for visible contamination where detector saturation must be avoided. Surface loadings of 3 µg VX, Russian VX, demeton-S-methyl, and isoprobenphos produced high responses, automatically identified with match factors ≥96/100. Limits of detection ranged from 20-200 ng on glass surfaces (MF≥85), depending on analyte. The high-load mode achieved 100% identification with match factors ≥99 for 1-mg deposits. The workflow is simple, requires minimal equipment, and is operationally feasible for reliable on-site confirmation of V-type agents using portable GC/MS during CBRN field operations. Although certain structurally related organophosphorus compounds yield identical fluoridates, the method provides sufficient specificity to indicate a toxic precursor.