User:Patrick Hampson/Notebook/chem471/2017/03/07

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Solution Preparation We prepared solutions which contained the normal amount of Arginine and Cysteine we use when only using 1 AA. (2x the normal concentration) We prepared a second stock of solutions which contained 0.5 the amount of Arginine and cysteine, to make for the equivalent concentration of AA we normally use. We then varied which AA was added to the gold first, and gave the solution a few minutes to react before adding the second AA. The second AA was then added, then the proper amount of H20, then the pH adjuster For each of the above solutions, we made one pH9 and one pH12 solution. We have 8 solutions in total: 2x [total AA]: -pH9, C 1st -pH9, A 1st -pH12, C 1st -pH12, A 1st 1x [total AA]: -pH9, C 1st -pH9, A 1st -pH12, C 1st -pH12, A 1st The solutions with 2x [total AA] formed no visible Au-S polymers in any solution. pH 9, C 1st has minor polymer formation on the bottom but much less than we have ever previously seen. The solutions with 1x [total AA] formed visible polymers in both pH9 solutions. Minimal polymers were formed in pH12, C 1st, while none were formed in the A 1st solution. This could be due to C making polymers early when it was just C and Au in the test tube (which was observed). The addition of A to the test tube degraded some of the polymers, but the addition of base to the solution (which had previously dissipated all polymers present) did not get rid of the polymers present (even though they are minuscule to begin with) 2/22/17 gold pH6 yellow tinge -light pH7 Navy blue coloration - light pH8 yellow tinge -light pH9 yellow tinge -light pH10 yellow tinge -light pH11 slight pink tinge -very light pH12 purple tinge -light Insert content here...