A sensitive method for quantification of short-chain fatty acids by benzyl chloroformate derivatization combined with GC–MS
The short-chain fatty acids (SCFAs) were identified as the critical marks in the diagnosis of chronic and metabolic diseases, but a sensitive and stable method to determine SCFAs in feces is a challenge for analysts for its high violatility. Herein, a sensitive and accurate method to determine SCFAs adopting precolumn derivatization coupled with gas chromatography–mass spectrometry (GC–MS) was developed. Benzyl chloroformate (BCF) was chosen as the reaction reagent and emulsified derivatization was applied to homogenizing the reaction system. Higher sensitivity, wider application and satisfactory derivatization efficiency were obtained in the developed method. An excellent method validation exhibited a good linearity ranging from 0.9947 to 0.9998. At the same time, the intra-day and inter-day precision were achieved in the range of 0.56% to 13.07%. The lower limits of detection of all target analytes varied from 0.1 to 5 pg. The recovery ranged from 80.87% to 119.03%, and storage stability under three different conditions was also verified. This method was also successfully applied to the analysis of SCFAs in mice fecal samples to illustrate the significant differences between normal and type 2 diabetes mellitus mice.