Isotope-Coded Chemical Derivatization Method for Highly Accurately and Sensitively Quantifying Short-Chain Fatty...

Area of Science:

• Metabolomics
• Microbiome research
• Analytical chemistry

Background:

• Short-chain fatty acids (SCFAs) are crucial gut microbiota metabolites influencing intestinal health and immunity.
• Quantifying low-concentration SCFAs in biological samples like serum and digesta is challenging with conventional GC methods.

Purpose of the Study:

• To establish a sensitive and comprehensive liquid chromatography-mass spectrometry (LC-MS) method for SCFA quantification.
• To improve SCFA detection sensitivity and separation using 5-(dimethylamino)-1-carbohydrazide-isoquinoline (DMAQ) derivatization.

Main Methods:

• Development of a novel LC-MS method involving DMAQ derivatization for SCFA analysis.
• Utilized DMAQ-¹³C/¹⁵N-tagged SCFAs as internal standards to minimize matrix effects.
• Applied the method to quantify SCFAs in plasma and cecum digesta from neonatal piglets.

Main Results:

• DMAQ derivatization significantly enhanced detection sensitivity and improved SCFA separation, enabling quantification of individual isomers like 2-methylbutyric and 3-methylbutyric acids.
• The method effectively reduced matrix effects using stable isotope-labeled internal standards.
• Analysis of piglet samples revealed a correlation between increased cecal SCFA levels and altered gut microbial diversity.

Conclusions:

• The developed LC-MS method provides a sensitive and comprehensive approach for SCFA quantification.
• This method can offer valuable insights into gut-microbiota functions and their metabolic outputs.
• The findings highlight the relationship between SCFA variations and gut microbial community structure in early life.