User:Elaine Marie Robbins/Notebook/CHEM-496/2012/02/01

Objective

To determine the effects of tris buffer (pH 10.1) on nanoparticle solution and protein fiber solution as a function of concentration and time.

Description

1. Take UV-vis data of 70 and 166 Au/BSA solutions prepared on 01/31/12.
2. Take UV-vis data of 0.9 mL of each AuNP solution + 0.1 mL of the following dilutions of tris (pH 10.1):
   • 50 mM
   • 5.0 mM
   • 0.50 mM
   • 0.050 mM
3. Continue to take UV-vis data of 0.9 mL 70 Au/BSA ratio + 0.1 mL 50 mM tris buffer solution over time.
4. Continue to take UV-vis data of 1 mL 70 Au/BSA ratio solution over time.

Data

• Graph of the absorbance vs wavelength data shift due to change in buffer concentration for 70 Au/BSA ratio solution:

• Graph of the absorbance vs wavelength data shift due to change in buffer concentration for 166 Au/BSA ratio solution:

• Graph of the absorbance vs wavelength data shift due to time elapse for 70 Au/BSA ratio solution:

• Graph of the peak absorbance vs -log(ion strength of tris buffer solution):

• Graph of the peak wavelength vs -log(ion strength of tris buffer solution):

Notes

The only buffer concentration that produced a shift for the 70 Au/BSA ratio solution in the peak absorbance value was the 50 mM Tris buffer solution (pH 10.1).

No change was observed in the 166 Au/BSA ratio solution.

Absorbance values increase as time elapses for the 70 Au/BSA ratio solution, however there is no shift in peak absorbance value.