2023 Volume 72 Issue 10.11 Pages 431-440
The method of analyzing carbonyl compounds by derivatization with 2,4-dinitrophenylhydrazine (DNPH) has been widely applied in various fields, and it entails the use of high performance liquid chromatography (HPLC) with ultraviolet/visible (UV/Vis) detection to identify and quantitate analytes. It is a very important issue with chromatography in the field of odor to separate structural isomers coexisting in a sample, because the odor of a substance arises from the molecular structure of the substance. Additionally, attention must be given to not only the structural isomers of the objects being measured but also the stereoisomers (syn/anti isomer) of the DNPH derivative in the separation of DNPH-derivatized carbonyl compounds. In this study, we examined HPLC measurement conditions for 6 aldehydes of specified offensive odor substances defined by the Offensive Odor Control Law in Japan, and confirmed the validity of the measurement method. In the experiment, 18 carbonyl compounds-DNPH mixed solution containing both syn-isomer and anti-isomer of DNPH derivatives was used as the simulated sample of the eluate from gas-collected DNPH cartridge. The result of the examination revealed that all of the 6 aldehydes were sufficiently separated by using a C8 column. According to the verification of the measurement data under optimized condition, it was shown that linear standard curves were obtained in the concentration range of 0.05 μg mL−1 - 1 μg mL−1, and the reliability of analysis values was secured. Furthermore, the measurement method established in this study was applied to the exhaust gas from an industrial plant, and the effect of each aldehyde on the odor around the plant was considered.
