Measurement of Trace Dihydroxybenzonic Acid Using GC-MS

摘要

In order to increase the sensitivity of OH radicals measurement using salicylic acid (SA) as a probe, the reaction product of OH radicals and salicylic acid, 2,5-dihydroxybenzonic acid (2,5-DHBA) and 2,3-dihydroxybenzonic acid (2,3-DHBA), were fluorided with pentafluorobenzyl bromide, and the derivatives of bis(pentafluorobenzyloxyl)-benzoic acid pentafluorobenzyl ester (BPBAPE) were then detected with a GC-MS. The molecule strctures of the final derivatives were identified using GC-MS and Nuclear Magnetic Resonance (NMR), and their mass spectrums under EI, NCI, and PCI mode are first reported. The detect limit of 7.2 nmol/L and 16.9 nmol/L for 2,3-BPBAPE and 2,5-BPBAPE, respectively, were obtained, with 1 μL injection into GC.