2020 Volume 33 Issue 5 Pages 70-78
2,4-Dinitrophenylhydrazine (DNPH) is one of the most common derivatizing reagent used for an analysis of aldehydes or ketones. Derivatives produced by this reaction are readily detected by UV/Vis photospectrometer or LC/MS. However, during the derivatization, an excess amount of DNPH is added to a sample and a large part of it remains unreacted. Injecting this residual DNPH into an analytical instrument may lead to some negative effects such as a damaged LC column, or a clogged sampling cone, probably resulting in an impaired detection sensitivity. It is therefore of importance to remove unreacted DNPH prior to an analysis.
The objective of this study is to develop a purification method for a DNPH-derivatized sample. Solid phase extraction (SPE) was focused on as a strategy to achieve this. The SPE purification method developed in this study removed 97.5％ of unreacted DNPH and recovered 103％ of a derivative. Additionally, quantum chemistry calculation was adopted to verify the experimental results. The calculation results were in good accordance with the experimental ones, i.e., the complexation between DNPH and a sorbent was more stable than that between a derivative and a sorbent.
