Blood glucose test

A blood glucose test measures the glucose levels in your blood. Glucose is a type of sugar. It is your body's main source of energy. A hormone called insulin helps move glucose from your bloodstream into your cells. Too much or too little glucose in the blood can be a sign of a serious medical condition.

1. BLOOD GLUCOSE TEST AZEEM ASLAM BS BIOCHEMISTRY LAHORE GARRISON UNIVERSITY

2. Principle : The enzyme glucose oxidase catalysis the oxidation of glucose to gluconic acid and hydrogen per oxide (H2O2). Addition of enzyme per oxidase and a chromogenic oxygen acceptor, such as ortho- dianasidine , result in the formation of a colored compound that can be measured at 546nm.

3. Blood Glucose Test :

4. Reaction : Glucose + O2 H2O2 + Gluconic acid H2O2 + Reduced chromogen(uncolored) H2O + Oxidized chromogen(colored)

5. Reagents for Test: 1. A 100ml of sodium hydroxide is taken with distilled water. 2. Zinc sulfate solution (55ml in amount) will then be diluted with sodium sulfate solution. 3. Take a phosphate buffer 0.5M in quantity whose pH should be 7.2. 4. Dissolve 25ml of 25mg of glucose oxidase in the buffer. 5. Now add 25ml of peroxidase to the buffer to take it up to quantity of 250ml. 6. This solution is active and can be used even after 4 weeks if kept at 4˚C in a colored bottle which must be brown.

6. Procedure : 1. Collection of blood sample. 2. Take 0.1ml of blood and pour it in a solution of sodium sulfate zinc sulfate reagent, take all of this solution in a centrifuge tube. 3. After adding sodium hydroxide (0.1ml in amount) in the centrifuge tube in the present solution, centrifuge all of this solution at 3000rpm for 5min. the supernatant of 0.5ml must be taken in duplicate after that. 4. Add 5ml of glucose oxidase reagent incubate for 1hr at 37˚C and read the extinction at 540nm against the reagent blank. 5. If the absorbance reading of the sample is too high, dilute the supernatant which was obtained earlier, 2x with distilled water and repeat the subsequent step.

7. Result : Normal Glucose Level : 3.9 – 5.5mmol/L.

8. Video Description : https://youtu.be/rMMpeLLgdgY