User:Melissa Novy/Notebook/CHEM-571/2012/11/27

Objectives

• Analyze solutions of AuHRP and AuADA, both made on 2012/11/14 with UV-vis.
• Make solutions of AuADA with dialyzed ADA.
  • ADA dialysis began on 2012/11/14 and ended on 2012/11/27.
  • Please refer to Keyun Wang's entry for the procedure used to remove the ADA from the dialysis tubing and prepare it for use in AuADA solutions.

UV-Vis on AuHRP and AuADA

• Exactly 3 mL of each solution was pipetted into a quartz cuvette for analysis using an automated pipetter (Pipetman).
• Please refer to Dhea Patel's entry for photographs of the solutions.
• Observations:
  • Small pellets of fibers were visible in all AuHRP solutions except 60 AuHRP. The 60 AuHRP solution did not contain a fiber pellet. All AuHRP solutions were purple in color.
  • AuADA solutions were colorless and contained no aggregates.

• The spectra for all solutions displayed a peak at around 520 nm, which indicates the presence of GNPs. The general trend was that the absorbance of these peaks increased as the mole ratio of Au:HRP increases. This implies that the amount of GNPs in solution increased in accordance with the amount of gold initially added to each solution.
• However, the peak absorbances for the 130 and 140 AuHRP solutions were almost identical. This is likely because the 130 AuHRP solution contained 1 mL less of H₂O due to an error during preparation of the solution.

Synthesizing AuADA Solutions

• Please refer to the protocol on 2012/11/14. There were no deviations from the protocol and the same stock solution of HAuCl₄ was used. However, dialyzed ADA was used instead of ADA in FPLC elution buffer.
• Please refer to Keyun Wang's entry for observations made during the procedure.