Question

Which of these properties is not true for mediators?

(a) Mediators must react rapidly with a reduced form of enzyme

(b) Mediators must be sufficiently soluble in oxidized and reduced forms

(c) The reduced form of the mediator should not readily react with oxygen

(d) Increasing the heat output

This question was addressed to me during an online interview.

Question is from Amperometric Biosensors in chapter Biosensors of Enzyme Technology

Answer 1

The correct answer is (d) Increasing the heat output

Explanation: The properties which are true for mediators used in amperometric biosensor are as follows:

• Mediators must react rapidly with reduced form of enzyme.

• Mediators must be sufficiently soluble in oxidized and reduced forms.

• The reduced form of the mediator should not readily react with oxygen.

• The over potential for the regeneration of the oxidized mediator should be low and independent of pH.

Increasing the heat output is true for thermistors used in calorimetric biosensor.