Further Testing of Strips

After we had concluded that we could indeed achieve a color change by adding a concentrated glucose solution, with the concentrations of reagents that we had chosen, and by applying them in layers onto filter paper, we did some tests to learn more about the sensitivity and limitations of this method. 

Firstly, we created glucose solutions of 100 mg/dL and 150 mg/dL, and this was in order to test actual blood glucose levels on our strip. 100 mg/dL and 150 mg/dL are the concentrations glucose should lie between if the test was done at a random time interval (i.e., not after fasting for 8 hours, like some blood tests are done). When we applied these glucose concentrations to our strips, we saw a color change for the 150mg/dL, but a significant lack of change for the 100mg/dL solution. This was interesting, because it meant that our reagent concentration choices were quite good, and our strip was sensitive to tell the different atleast between the limits of real blood glucose levels. 

Secondly, we tested the order in which reagents should be applied to the filter paper. We had three reagents to apply, the dye (D0), Horseradish Peroxidase (P0) and Glucose Oxidase (G0), and we alternated the order of each. From the image, you can see that we found that the best order was the one listed above, and the one that we had initially used for our tests, dye followed by the peroxidase followed by the glucose oxidase.