User:Michaela Harper/Notebook/Biological Chemistry Lab/2012/03/07

Au/BSA Mole Ratios

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Objective To analyze various ratios of solution made on 03/06/2012 To determine the effect of the mole ratio of Au/BSA on AuNP synthesis by refining the range in which the greatest change occurs. Description Effect of Au/BSA Ratio Make solutions with the following Au/BSA mole ratios using 0.1 mL HAuCl4: 132 Au/BSA 134 Au/BSA 136 Au/BSA 138 Au/BSA 140 Au/BSA 142 Au/BSA 144 Au/BSA 146 Au/BSA 148 Au/BSA Dilute to 1 mL with water. Place in oven at 80°C. Leave solutions in oven for 3 hr. Centrifuge solutions at 13200 rpm for 10 min. Take UV-vis data of supernatants. Data The following graphs show the effect of varying ratios in between the purple nanoparticle solution ratio (70) and the fiber solution ratio (166). This data is from solutions made on 03/06/2012. The following graph shows the relationship between the ratio of Au/BSA and the peak absorbance. The following graphs show the effect of varying ratios in a smaller range (130-146 Au/BSA) to identify the ratio at which there is no longer a nanoparticle peak around 550nm. Notes The data from solutions with ratios varying between the purple solution and fiber solution (between 70 and 166) showed a dramatic decrease between 130 and 150 Au/BSA, indicating a switch to more fiber formation. This led us to test more ratios in between 130 and 150, with increments of 2 to refine the range where the change occurs. The 148 Au/BSA had no fiber formation and was completely clear so that sample was disregarded and no data was collected for that point. Data for 130-146 was obtained to show that a marked decrease in the peak occurred between 132 and 134, indicating that this is the point at which nanoparticle solution can no longer be made and fiber formation begins.