Tributyl phosphate assisted hollow-fiber liquid-phase microextraction of short-chain fatty acids in microbial degradation fluid using capillary electrophoresis-contactless coupled conductivity detection.

A tributyl phosphate assisted hollow-fiber liquid-phase microextraction coupled with capillary electrophoresis-contactless coupled conductivity detection (HF-LPME/CE-CD) method has been developed for trace analysis of common short-chain fatty acids (SCFAs) without derivatization. Under the optimum conditions, ten SCFAs including a pair of isomers were well separated from their homologous FAs and the main coexisting inorganic anions within 40 min. Tributyl phosphate assisted HF-LPME produced excellent purification and enrichment for the model sample with high-salt matrix, microbial degradation fluid, and the limits of detection could reach 0.072-0.67 ng/mL (S/N = 3). Owing to its high sensitivity, good linearity, and acceptable recovery, this proposed method provided a sensitive and environment-friendly alternative for trace analysis of SCFAs in complicated samples.