ABSTRACT
Rose Bengal is used as a photo sensitizer in photo galvanic cell for solar energy conversion and TEAis used as an electron donor in this study. The effects of various parameters like pH, light intensity, diffusion length, reductant concentration and dye concentration on the electrical output of the cell is studied. The photo potential and photocurrent generated by this cell are 840 mV and 145μA, respectively. The current voltage (i–V) characteristic of the cell is also studied and a mechanism for the generation of photocurrent is proposed.
ABSTRACT
Antioxidative activity is an important factor in inhibiting oxidative stress. The usual methods for determining antioxidative activity are time-consuming and cumbersome. They are also indirect processes that use biological material such as brain or liver microsome. This study therefore proposed a new method. Redoxpotential was determined using galvanic cell with or without the addition of various antioxidants or herbal extracts in zinc sulfate solution. The result was compared with the results from the TBA method and the peroxide value from sodium thiosulfate titration. All methods showed significant and dose-dependent enhancement of antioxidative activity by adding ascorbic acid, quercetin, ginseng, or gingko biloba extract. The result of redox potential using galvanic cell showed the smallest standard deviation and took the shortest time among the three methods. Therefore, the antioxidative potential of chemical substances and herbal extracts can be determined simply, directly and accurately in a short period of time using galvanic cell.