Determination of alditols and carbohydrates of food interest using a sulfonated monodisperse resin-based column, coupled with pulsed amperometric detection (PAD) and postcolumn PH adjustment

Carbohydrates such as glucose, fructose, sucrose, and sugar alcohols mannit ol, sorbitol, and xylitol are widely distributed in various foods and bever ages. In this work we developed a HPLC method for the determination of sugars and alditols, using a sulfonated monodisperse resin-based column in hydrogen f orm (PL Hi-Plex, 300 x 7.7 mm, from Polymer Laboratories), coupled with pul sed amperometric detection (PAD). Performing isocratic separation using wat er as the mobile phase, post column addition of 0.5 M sodium hydroxide was necessary to detect sugars and alditols by PAD. After the optimization of t he operating conditions, the method was characterized and validated in term s of selectivity, repeatability, sensitivity, and accuracy. Furthermore, qu antification of lactose, glucose, and galactose in lactose-hydrolyzed milk products was found to be highly accurate.