Automated flow system on-line to LC with postcolumn derivatisation for determination of sugars in carbohydrate-rich foods

Abstract

KeyWordsColumn liquid chromatography Postcolu mn derivatisation Sugars Carbohydrate-rich foods SummaryA method for the direct determination of carbohydrates in foods using an automated-flow system coupled on-line to a high-performance liquid chromatograph is proposed. The method is based on postcolumn clerivatisation of reducing sugars with p-aminobenzoic acid hyclrazide in an alkaline medium following elution from the chromatographic column with an acetonitrile:water graclient as mobile phase. The manifold allows non-reducing sugars to be hyclrolysed prior to insertion into the chromatograph, thus making them compatible with the clerivatisation reaction and with continuous clecolorisation of the sample on an activated carbon column. The method allows determination of six sugars in contents bef,,veen 0.005 and 4% (w/v) with high precision (3.8 -5.0% RSD). For analytical validation, it was applied to determination of fructose, sucrose, maltose, lactose and maltotriose in l",,vo reference materials (milk powder and sugar). Finally the method was used to determine sugars in a varie b, of carbohydrate-rich foods.

An HPLC Method for Microanalysis and Pharmacokinetics of Marine Sulfated Polysaccharide PSS-Loaded Poly Lactic-co-Glycolic Acid (PLGA) Nanoparticles in Rat Plasma

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Autoanalyzer for Milk Quality Control Based on the Lactose, Fat, and Total Protein Contents

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