Gluconic acid produced by oxidation of glucose has strong chelating action and is used in the medical and food fields. In this application, glucose and gluconic acid were analyzed by LC/MS method using HILICpak VG-50 2D, a polymer based HILIC mode column. Alkaline conditions were found to be suitable for high sensitive detection of saccharides under the negative mode, and are able to suppress the adsorption of organic acids.


Sample : 5 μL
10 ng/mL each
(in H₂O/CH₃CN=1/4)
1. Glucose
2. Gluconic acid

Column       : Shodex HILICpak VG-50 2D (2.0 mm I.D. x 150 mm)						
Eluent       : 0.5 % NH3 aq./CH3CN=30/70					
Flow rate    : 0.2 mL/min						
Detector     : ESI-MS (SIM Negative)						
Column temp. : 40 °C