2001 Volume 47 Issue 1 Pages 75-77
The toxic solution used at the Tokyo Subway Sarin Incident was purified by vacuum distillation. We were thus able to obtain sarin with high purity. We conducted a quantitative analysis of sarin using 31P-NMR spectrometry. High-purity sarin was examined by trimethyl phosphate as an internal standard. In comparison with 1H nondecoupling, the relative intensity between sarin and the internal standard did not change in 1H decoupling. Trimethyl phosphate is a good internal standard substance. A 31P-NMR chemical shift of trimethyl phosphate is separate from those of sarin and related compounds. Trimethyl phosphate has one phosphorus atom in the molecule, as does sarin. Since it is advantageous in the conversion of quantitative value, the molecular weight of trimethyl phosphate (m.w. 140.08) is close to that of sarin (m.w. 140.09). By using trimethyl phosphate as an internal standard, it is possible to conduct a quantitative analysis of sarin through 1H decoupled 31P-NMR spectrometry.
