Abstract: A method for the quantitative determination of sugars in a fluid sample. The sugar sample, which may contain free glucose, is passed through a scavenger stage where substantially all of the glucose is removed, so that it does not interfere with the determination. The glucose-free sample is then passed through an immobilized glucose generating stage to produce glucose in molar proportion to the total initial concentration of the sugars present. The generated glucose is passed through an immobilized hydrogen peroxide generating stage to form gluconic acid and hydrogen peroxide. The generated hydrogen peroxide is detected in suitable detection means, typically a polarographic cell. Total free glucose is determined by measuring the total sugars in the sample by bypassing the scavenger stage, determining total sugar, then determining the glucose in the sample without bypassing the scavenger and measuring free glucose as the difference.

Abstract: A carbohydrate substrate such as starch for a carbohydrate hydrolyzing enzyme is immobilized on a solid inorganic porous support to form a stable substrate-support composite useful in affinity chromatography and in methods where a precise amount of substrate is needed to perform an enzyme-substrate reaction to quantify the enzyme. The substrate may be activated with an agent such as cyanogen bromide or imidazole prior to deposition on the support so that it may be effectively modified while on the support. After deposition, the substrate is modified by reaction with an epoxyhalogen, aliphatic dihalide or aliphatic diamine to aid in holding it on the support. In an alternative embodiment, the carbohydrate, prior to deposition and modification on the support, is hydrolyzed with an enzyme, preferably dextranase.