Enhancing sensitivity of liquid chromatographic/ion-trap mass spectrometric determination of jasmonic acid by derivatization with N,N′-dicyclohexylcarbodiimide

Abstract

A simple and sensitive method for the detection of jasmonic acid (JA) by liquid chromatography-ion trap mass spectrometry (LC-IT-MS/MS) after derivatization is described. The highlight of this method was that it involved a rearrangement reaction which was often considered as a side reaction in the formation of amides and esters using N,N′-dicyclohexylcarbodiimide (DCC) as a condensation reagent. While in this study, DCC was used as a derivatization reagent directly. Internal standard dehydrojasmonic acid (DHJA) was used to ensure the accuracy. Derivatives provided good signals corresponding to the protonated molecular ions [M + H]⁺ and product ions. Sensitivity had been improved 100-fold with the LOD being 0.1 ng mL⁻¹ in comparison with the LC-IT-MS analysis without derivatization. This proposed method was reliable with good recoveries found in rice floret and wintersweet, allowing quantification in real samples to be more accurate and efficient, thus offering a good way to further study the physiological and biological activities of jasmonic acid in plants.