Ion-Pair RP-HPLC Determination of Sugars, Amino Sugars, and Uronic Acids after Derivatization with p-Aminobenzoic Acid

摘要

A new, selective, and sensitive ion-pair RP-HPLC method for the simultaneous determination of three classes of natural organic compounds, i.e., carbohydrates, amino sugars, and uronic acids, in environmental samples is presented. p-Aminobenzoic acid is used for precolumn derivatization of the analytes, enabling fluorescence (λ_(ex) 313 nm, λ_(em) 358 nm) or photometric detection (303 nm). The dependence of the derivatization yield on the reaction conditions is examined. Derivatives of lactose, galactose, glucose, mannose, xylose, arabinose, galacturonic acid, glucuronic acid, N-acetylglucosamine, and glycerinealdehyde were separated on a RP-C_(18) column with hydrophilic end capping within 35 min, applying TBAHSO_(4) as the ionpair reagent. The concentration detection limits range between 20 and 30 μg L~(-1) ((1-2)×10~(-7) M) for fluorescence detection and between 30 and 75 μg L~(-1) for UV detection. A good linearity is achieved in the concentration range from 50 μg L~(-1) to 100 mg L~(-1) (r~(2)>0.99). The described method has been applied for the determination of mono-/disaccharides, uronic acids, and amino sugars in soil solutions and in landfill leachates.