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Rudi, et al.

The identification of DMMP in the presence of 3.4. Real sample analysis
interfering chemicals, such as hydrocarbons and diesel, The proposed method of validation was used for a real
which are typically introduced to PT samples to challenge sample, which was the OPCW 52 PT sample. From the
nd
the analytical process, provided the last evidence of preliminary report by OPCW, DMMP was one of the
the method’s specificity. Indeed, recent research by spiking chemicals for sample 525 with a concentration
Sassolini et al. and Konopski et al. indicated that of 5 ppm. The proposed method was able to extract
16
6
achieving specificity in such complex matrices was and qualitatively detect DMMP in sample 525 with an
challenging for LLE; in fact, lower accuracy was accuracy of 95.6%. The extracted ion chromatogram and
seen when contaminants were present in the sample. mass fragmentation of DMMP are shown in Figure 3.
In contrast, the QuEChERS approach demonstrated
exceptional resilience in this investigation, even when 4. Conclusion
there is significant matrix interference, by offering high
recoveries and accuracies at 96.2%. The validation and application of the GC-MS method
for analyzing CWC-related compounds, DMMP, in the
Table 2. Accuracy of the proposed method context of OPCW PT, have proven highly successful. The
Analyte Intraday precision Interday precision study demonstrated that the validated approach, utilizing
the QuEChERS extraction methodology, is both reliable
RSD (%) RSD (%) and effective for detecting CWAs-related compounds.
5 ppm 15 ppm 5 ppm 15 ppm The method exhibited a remarkable linearity with a
DMMP 4.2 3.5 4.8 3.7 correlation coefficient of R² = 0.9998, indicating an
Abbreviation: RSD: Relative standard deviation. excellent linear response across the studied concentration
range. Furthermore, the low LOD at 0.0167 ppm and
LOQ at 0.0557 ppm confirm the method’s sensitivity
for detecting low concentrations in complex matrices.
The application of this validated method to an authentic
sample from the 52 OPCW PT resulted in a recovery
nd
rate of 95.6% for DMMP, demonstrating the method’s
efficiency and robustness. This approach not only
meets the stringent requirements for OPCW PT but also
enhances the analytical capabilities for the detection of
CWC-related compounds. Consequently, it contributes
significantly to ongoing global non-proliferation efforts,
reinforcing the importance of reliable methodologies
in the monitoring and control of chemical weapons.
The future work will focus on further validation using
actual G-series nerve agents in collaboration with an
OPCW DL. This would provide a direct comparison
between DMMP and real CWAs, ensuring the method’s
applicability in real-world scenarios.

Acknowledgments

The authors would like to thank the Department of
Chemistry, Universiti Malaya, for the vital facilities
and support throughout this study. We would like to
acknowledge Universiti Pertahanan Nasional Malaysia
Figure 3. Extracted ion chromatogram of DMMP (UPNM) for the great opportunity to cooperate and
(top) and mass spectra of DMMP (bottom) for the important contributions. Special thanks go to
Abbreviation: DMMP: Dimethyl methylphosphonate the Science and Technology Research Institute for

Volume 22 Issue 2 (2025) 48 doi: 10.36922/ajwep.8196