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

Table 3

Evaluation of the chromatographic peak area of sarin 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
	Sarin	Triethyl-phosphate	Sarin	Triethyl-phosphate	Sarin	Triethyl-phosphate
Retention time (min)	7.4	13.2	5.1	11.7	7.1	13.3
Linearity range (mg/L)	1–40	2.5–40	0.5–10	0.5–15	5–40	5–50
R	0.9999	0.9986	0.9998	0.9996	0.9979	0.9988
QC	1.07	3.68	1.74	2.22	3.84	3.71
Gradient (A × 10^−6 × L/mg)	2.9	1.4	0.74	0.38	0.040	0.020
Intercept (A × 10^−6)	0.18	−0.24	−0.030	0.014	0.0088	0.0073
Response factor FR	2.06		1.93		1.97
Average value of FR			1.99