Yes. In fact, one can get great Raman from Ag and Au nanoparticles due to surface enhancement. Just look up surface enhanced Raman spectroscopy (SERS). The set-up is a usual Raman set-up and you can perform these experiments on a colloidal solution of Ag and Au nanoparticles. For Au use red laser to get the Raman and for Ag you can used green or blue lasers as well. There are certain complications arising from the deformation of the molecules at the surface which may modify the Raman spectrum somewhat. In in your case you may be requiring just that as these changes in the Raman spectrum originate from structural changes.

There are several good reviews on the subject just start with any one. Most groups use a microscope for SERS but you don't necessarily need it.

Now about collecting Raman from one particle. Yes TERS is a way of doing that. However if your particle size is large (micrometer) a microRaman set-up can do that too (I am assuming that your substrate is not moving). I have no personal experience with TERS but my impression is that it is not a particularly easy experiment to do. Hope this helps.

Best of luck.

I suspect that you are talking about measuring surface modified nanoparticles in solution. If this is the case, you may want to try taking the measurements in a flow cell. The signal you will obtain is due to nanoparticles passing through the focal plane of the incident laser beam. Since the naanoparticles are in solution, you will have a lower signal than on a stationary/dry surface due to the fact that nanoparticle concentration in the focal plane of the laser is constantly changing. I would suspect that you could determine some signal if your nanoparticle concentration was high enough and you were able to acquire signal for a long period of time (>2 minutes or so may be sufficient).