From the BD web site
What is the glycolytic inhibitor in the gray top tube?
Sodium fluoride acts as the glycolytic inhibitor and prevents the cells in the blood from utilizing the glucose.
It is the gray coloured tube that's used for Glucose testing. Refrence is the Phlebotomy Today textbook fourth edition published by Wolters Kluwer health.
the color tube is either gray or red..
serum
ABG is collected in a green heparinized tube or heparinized syringe.
Glucose studies use gray top tubes. The additive in grey tubes prevent glycolysis. Lactic acid test also uses a gray top.
Gray tube
fine glucose molecules can pass through the wall of the visking tube.
Gray top tube
Clotting
Diabetes testing is important for effectively managing the disease. Diabetics should perform their own testing daily with a glucose meter. A1C testing is ordered several times a year by doctors to check overall glucose levels.
Gray.
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