Which additional substance is necessary for the oxidation reaction in a blood glucose meter?

• A. FAD
• B. NADH
• C. H2O
• D. Acetyl-CoA

Answer: (A)

In the context of a blood glucose meter, the oxidation reaction involves the oxidation of glucose to produce gluconolactone, which is facilitated by an enzyme, commonly glucose oxidase. This process typically requires a coenzyme that can accept electrons during the oxidation of glucose.

FAD (flavin adenine dinucleotide) serves as an electron carrier in various biological oxidation-reduction reactions. In the case of glucose oxidation, FAD can accept electrons released during the oxidation process, allowing the continuation of the reaction. Hence, the presence of FAD is essential for the proper functioning of glucose oxidase and the overall reaction, as it ensures that the electrons are transferred appropriately and that products can be formed effectively.

The other options do not play a direct role in the enzymatic oxidation of glucose in this specific context. NADH is the reduced form of NAD+ and is involved in reduction reactions, not oxidation. Water is not a direct participant in the required oxidation for a blood glucose meter's operation, while Acetyl-CoA is involved in metabolic pathways related to energy production but is not necessary for the oxidation of glucose by glucose oxidase. Therefore, FAD is the critical coenzyme needed for the oxidation reaction to occur effectively.