Enzymatic method for the determination of D-Glucose. Based on the spectrophotometric measurement of NADPH produced though the reactions, after addition of hexokinase (HK) and glucose-6-phosphate dehydrogenase (G6PDH).
D-Glucose occurs widely in plants and animals. It is an essential component of carbohydrate metabolism and occurs frequently in the free form along with D-fructose and sucrose. However, the more important forms are those of di- (lactose, maltose, sucrose), tri-, oligo- and polysaccharides (dextrins, starch, cellulose). It is present in significant quantities in honey, wine and beer, and a range of solid foodstuffs such as bread and pastries, chocolate and candies. Measurement of D-glucose is extremely important in biochemistry and clinical analysis, as well as in food analysis; it is mostly determined along with other carbohydrates.
This rapid and simple specific enzymatic method is used for the determination of D-glucose in foodstuffs such as baking agents, diet beer and dietetic foods, as well as in pharmaceuticals, cosmetics and biological samples. The analysis of D-glucose in foodstuffs is normally performed in conjunction with D-fructose, maltose and sucrose.
Solution 1. Imidazole buffer (25 mL, 2 M, pH 7.6) plus MgCl2 (0.5 M), MgCl2 (100 mM) and sodium azide (0.02 % w/v) as a preservative. Stable for 2 years at 4 °C. Solution 2. NADP+ (150 mg) plus ATP (440 mg). Stable for 5 years at -20 °C. Dissolve in 12 mL of distilled water, divide into appropriately sized aliquots and store in PP tubes at -20 °C between use (stable for 2 years) and keep cool during use. Suspension 3. Hexokinase (EC 188.8.131.52; 425 U/mL) and glucose-6-P dehydrogenase (EC 184.108.40.206; 212 U/mL) in 3.2 M ammonium sulphate (2.25 mL). Stable for 2 years at 4 °C. Swirl bottle before use. Solution 4. D-Glucose standard solution (6 mL, 0.40 mg/mL) in 0.02% benzoic acid. Stable for 2 years at room temperature. This standard solution can be used when there is some doubt about the method accuracy.
Compatible Sample Types:
Wine, beer, fruit juices, milk, dietetic foods, bread, jam, honey, ice-creams, fruit and vegetables, pharmaceuticals, cosmetics and biological samples.
Features & Benefits:
Rapid reactionsSuitable for manual and micro volume formats
Reaction volume: 2.32 mLRange: 2-800 mg/LDetection limit: 0.66 mg