Thank you for your suggestion, we want to check in vivo antibacterial activity of the substance. In vitro assays already showed that the substance has an activity against E.coli by Disco-diffusion method.
I think in vivo is a complicated task. How do you evaluate the test bacterium in a particular organ? If you spread plate overall dilution from the infected organ or tissue, other cultures also develope colonies along with the test culture. Even in the advanced labs it is not easy to esmitate in vivo. SEM can be useful tool for that, but even in that case you should visually differ the cells of the test pathogen. We have done this, but results were not so reliable. Besides we tested "kill-curve experiments" with E.coli, the method documented in our papers, which you can find here, in researchgate