I am trying to synthesize surface modified biogenic silver nanoparticles and would like to know how their surface changed how this modification affect on their biological activity and i am wondering what are tests recommended for this purpose
You can check the change in surface morphology by TEM analysis of your unmodified and surface modified NPs. To check the biological activity, you can do MTT assay by treating normal cell line like NIH-3T3. Moreover you can also check the anticancer activity of your NPs by doing MTT assay using various cancer cell lines.