Havent yet tried to encapsulate any bacteria using polymers. But you could try using biopolymers such PLGA or PVA for coating. Hope it reduces the size.

By definition, bacteria are micro-sized, and cannot be encapsulated on the nanoscale. If someone claims to have nanoencapsulated bacteria, they are misusing the term. The bacteria would, at best, be considered microencapsulated. That is not to say that nanotechnology cannot be used to encapsulate bacteria. I can, for instance, envision a bacterium coated with a large number of nanoparticles. That would not be the same as nanoencapsulation, though.

I agree with Greg Cota, 

The nano material can have 2 structures. one of them is a single nanoparticle and second is a matrix structure containing of nanoparticles. A single NP can not encapsulate the bigger particles but a matrix nanostructured material can encapsulate bigger particles. It is important to think about advantage and need of nanoparticulate systems. Always nanoparticulate systems are not necessary and helpful. In some case conventional methods are preferred. 

Yes, make sense. Thanks!

Hi,

Since it is not possible to encapsulate a miron-sized structure in nano-structures, we can encapsulate parts of the bacteria (e.g. enzyme, gene, plasmid, etc.) in nanocapsules for example to get the effect / functionality of that particular micro-organism. Remember: Nothing is impossible in science.

Hi,

I think by "layer by layer" method nano-encapsulation of bacterial could be accessible. In another word you can use a nano layer around the bacteria instead a capsule. Please see below link

Article Layer-by-Layer Nano-Encapsulation of Microbes: Controlled Ce...