| I. Chemical methods
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| A. Oxidation-reduction reaction
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| 1. Alkaline copper reduction
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| Folin-Wu method
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Blue end-product
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| Benedict's method
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- Modification of Folin–Wu method for qualitative urine glucose.
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| Nelson–Somogyi method
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Blue end-product.
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| Neocuproine method
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*
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Yellow-orange color neocuproine
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| Shaeffer–Hartmann–Somogyi
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- Uses the principle of iodine reaction with cuprous byproduct.
- Excess I2 is then titrated with thiosulfate.
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| 2. Alkaline Ferricyanide reduction
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| Hagedorn–Jensen
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Colorless end product; other reducing substances interfere with reaction.
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| B. Condensation
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| Ortho-toluidine method
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| Anthrone (phenols) method
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- Forms hydroxymethyl furfural in hot acetic acid
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| II. Enzymatic methods
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| A. Glucose oxidase
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| Saifer–Gerstenfeld method
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Inhibited by reducing substances like BUA, bilirubin, glutathione, ascorbic acid.
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| Trinder method
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| Kodak Ektachem
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- A dry chemistry method.
- Uses spectrophotometry to measure the intensity of color through a lower transparent film.
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| Glucometer
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- Home monitoring blood glucose assay method.
- Uses a strip impregnated with a glucose oxidase reagent.
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| B. Hexokinase
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- NADP as cofactor.
- NADPH (reduced product) is measured in 340 nm.
- More specific than glucose oxidase method due to G-6PO4, which inhibits interfering substances except when sample is hemolyzed.
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