An innovative method for simultaneous separation and determination of monosaccharide and sugar alcohol isomers associated with glycometabolism in beagle plasma using gas chromatography-mass spectrometry.

Background: Tracking changes in plasma concentrations of monosaccharides and sugar alcohols related to glycometabolism, which plays a role as the main source of energy, is of great significance for the treatment of metabolic diseases. However, analysis of monosaccharides and sugar alcohols has always been a difficult task due to the high polarity of the polyhydroxy structure and the presence of a large number of isomers. So far, no suitable method has been developed for simultaneous determination of monosaccharides and sugar alcohols in beagle plasma.

Results: This work performed an innovative gas chromatography-mass spectrometry method for the simultaneous chromatographic separation and absolute quantification of 11 monosaccharides and sugar alcohols associated with glycometabolism. After derivatization, monosaccharides converted to be oxime acetylated derivatives and sugar alcohols transformed into acetylated derivatives. All analytes achieved good separation after chromatographic conditions were optimized, especially the selection of mid-polarity capillary column(6 % cyanopropyl phenyl and 94 % dimethyl polysiloxane). The improvement of derivatization efficiency through single factor and response surface optimization ensured a high sensitivity, with LOQ of each analyte in the range of 0.2-50 ng/mL. The established method was fully validated in terms of linearity and range, sensitivity, accuracy and precision, recovery, matrix effect, stability, dilution integrity and proved to be reliable, which was applied to the comparative study on hypoglycemic effect of two antidiabetic agents with different pharmacological mechanisms, dorzagliatin and metformin, as well as possible metabolic pathways affected by them.

Significance: This method solves the problems of multiple peaks after derivatization and frequent co-elution of analytes in previous analytical methods, significantly enhances derivatization efficiency of ketoses, which provides a promising approach for simultaneous analysis of aldose, ketose, and sugar alcohol. It offers new insights into a more comprehensive research on glycometabolism rather than merely focusing on glucose.