High Sensitivity Analysis of Formaldehyde using NCI-GC/MS

Introduction

In June 1998, the Japanese Environment Agency created a list of items to be monitored for water environmental preservation, where 300 substances are listed. Procedure manuals for monitoring these substances issued by the Water Quality Bureau of the Environment Agency issued in December 1999 includes the method for analyzing formaldehyde, one of the substance to be monitored. According to this method, formaldehyde is derivatized with PFBOA (pentafluorobenzylhydroxylamine), and the produced PFBOA formaldehyde is analyzed by GC/MS. Quantitation should be conducted by SIM measurement with the EI (Electron Ionization) method. In the example introduced here, PFBOA formaldehyde was measured using the prescribed EI method, and also the NCI (Negative Ion Chemical Ionization) method. The NCI method detects negative ions generated by ion-molecular reaction or by electron capture reaction. This method achieves high-sensitivity analysis of compounds with high electron affinity, as well as halogenated compounds like PFBOA formaldehyde. SIM measurement with the NCI method achieved sensitivity 100 times higher than that of the EI method for PFBOA formaldehyde. As proved here, formaldehyde can be detected with higher sensitivity by using the NCI method.

August 26, 2004 GMT