Fluoride, used in the collection of blood samples for glucose estimation, inhibits the enzyme
Enolase requires Mg+ +, and by removing magnesium ions, fluoride will irreversibly inhibit this enzyme. Thus, fluoride will stop the whole glycolysis. So when blood collecting for sugar estimation, fluoride is added to the blood. If not, glucose is metabolized by the blood cells, so that lower blood sugar values are obtained.Ref: DM Vasudevan, 7th edition, page no: 111
Glucokinase
Hexokinase
Enolase
Glucose-6-phosphatase
Metabolism of carbohydrate