Week six

So at my last post I had just found an appropriate mix of salts and nano-particles. This allowed me to then mix in my DNA and start performing equilibrium dialysis. However, I immediately ran into another big problem. What was I to re hydrate my solutions with? In the past, at this step I was not using citrate nanoparticles, but I was re hydrating with TEM buffer. I was uncertain if this would be efficient with these new particles. I decided to head to the science center and discus this problem with Rich, a fellow user of similar nano-particles. We threw a few ideas back in forth, but nothing seemed like an exceptionally good idea to re hydrate with. So I had to make a sacrifice, I gave up any hope of getting to use the ICP-OES this run in order to figure out what to re hydrate my samples with. I split my total solution of nano particles into three parts, one would be re hydrated  with mili-Q, another with TEM buffer, and a third with a solution that was 10^-2 M NaCl. Unfortunately I was only re hydrating with 4mL each when I typically do double that. Regardless, the results appeared to be conclusive, showing that the salt buffer worked the best.

So then I had to restart once again. This time, I took all of my gold nano particles and coated them with PAH. I then spun them in the centrifuge for an increasingly long period of time to siphon out the supernatant and continue spinning that. Finally, I recombined the pellets and diluted it back to 7mL with more nano particles. So I'm left with 1 super concentrated gold nano particle sample and 7 other slightly less concentrated samples. They were then all mixed with DNA and left to sit over night. Now I am currently trying to perform equilibrium dialysis, and hopefully after doing this I'll finally be able to use the ICP-OES.