Internal Standards for Quantitative Analysis of Chemical Warfare Agents by the GC/MS Method: Nerve Agents

Table 5

Evaluation of the chromatographic peak area of cyclosarin and triethylphosphate at m/z 99 as a linear function of their concentration (critical values of the correlation coefficient R_CRIT 0.99 and QC coefficient QC_CRIT 5.00).

GC/MS compound	7890A/5975C		Intuvo 9000/5977B		EM 640
	Cyclo-sarin	Triethyl-phosphate	Cyclo-sarin	Triethyl-phosphate	Cyclo-sarin	Triethyl-phosphate
Retention time (min)	14.6	13.2	12.5	11.7	14.7	13.3
Linearity range (mg/L)	5–30	2.5–40	1–12.5	0.5–15	5–50	5–50
R	0.9998	0.9992	0.9996	0.9998	0.9969	0.9996
QC	1.62	2.82	2.01	1.28	4.45	1.68
Gradient (A × 10^−6 × L/mg)	3.2	1.5	0.78	0.38	0.046	0.021
Intercept (A × 10^−6)	−1.3	−0.29	0.0061	−0.017	0.022	0.0077
Response factor FR	2.17		2.07		2.18
Average value of FR			2.14