What is an overview of the iodine/LifePak demonstration mentioned by Dr. Chang?
A. For the demonstration, use any LifePak tablet. A small amount of water and 1-2 drops of iodine. When iodine and starch are mixed, the solution turns a dark blue. When titrated with vitamin C (or another antioxidant), the solution becomes clear. The starch in the LifePak capsules, from the millet which is used as an excipient, mixes with the iodine in the LifePak. As the starch and iodine mix together in the water, the solution turns a deep blue colour. Gradually, the vitamin C in LifePak has a chance to interact with the starch/iodine solution and the blue colour changes to a colourless solution. The chemical reaction is as follows: C6H8O6 + I2 = C6H606 + 2H+ + 2I- This is a classic reduction-oxidation reaction, and demonstrates vitamin C’s antioxidant capacity. The iodine ( I2) reacts with the ascorbic acid as it is formed during the titration. The reaction of the oxidation of ascorbic acid ( C6H8O6) by iodine produces dehydroascorbic acid (C6H6O6) .
