Thursday, July 1, 2010

Testing the mechanical properties of loose "extended" organic ligands on 0d nanoparticles

I am doing a literature review looking for information on a research project i am going to propose late this summer / early fall. I am interested in a simple test of the mechanical properties of extended ligands coming off gold nanoparticles 4-12nm in size.

The tircky part is that i do not want to test the entire shell of the nanoparticle, doing typical "compression" mechanical tests with an afm, rather i want to functionalize the nanoparticles with "laterally extended domains" which extend off the nanoparticle some 100 nanometers. Thus, i am faced with the challenge of synthesis of these nanoparticles. I believe the best route at this point given my skills is to cap with amines or mercaptoids and then do a replacement reaction with a agent that has a long carbon chain. The trick will be to do the reaction with such a small amount of regent (relative to the number of np in solution) such that only small portions of the np are covered. This may produce the desired result. Next would be to put these on a substrate and image with afm, trying to find an isolate nanoparticle to probe. Once found, the afm tip will be dragged across the extended domain, measuring the force resistance. Other characterizations can be done as well.