Quantification of saccharides in honey samples through surface-assisted laser desorption/ionization mass spectrometry using HgTe nanostructures.

Abstract

Quantification of monosaccharides and disaccharides in five honey samples through surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) using HgTe nanostructures as the matrix and sucralose as an internal standard has been demonstrated. Under optimal conditions (1× HgTe nanostructure, 0.2mM ammonium citrate at pH9.0), the SALDI-MS approach allows detection of fructose and maltose at the concentrations down to 15 and 10μM, respectively. Without conducting tedious sample pretreatment and separation, the SALDI-MS approach allows determination of the contents of monosaccharides and disaccharides in honey samples within 30min, with reproducibility (relative standard deviation <15%). Unlike only sodium adducts of standard saccharides detected, sodium adducts and potassium adducts with differential amounts have been found among various samples, showing different amounts of sodium and potassium ions in the honey samples. The SALDI-MS data reveal that the contents of monosaccharides and disaccharides in various honey samples are dependent on their nectar sources. In addition to the abundant amounts of monosaccharides and disaccharides, oligosaccharides in m/z range of 650 - 2700 are only detected in pomelo honey. Having advantages of simplicity, rapidity, and reproducibility, this SALDI-MS holds great potential for the analysis of honey samples.