I think with this kind of shot, it needs to be really sharp for it to have any impact. This looks like it is nicely focused, just not very sharp. A touch of USM would help immensely.
I like the lighting and the set up except for the syringe - are you adding something with the syringe? or is this going to be used to pick the solids up? I would think a drop coming out of the filled syringe would have been more dramatic (and more realistic).