(a) Bacteria-driven microswimmers on the basis of PEM-MNP microparticles attached to E. coli MG1655 bacteria. (A) Schematic design of bacteria-driven microswimmers for active targeted drug delivery. Note: PS = polystyrene microparticle (1 μ
m diameter). (B) SEM image of one single PS(MNP1
PAH-attached bacterium. (C) TEM image of thin section of a microswimmer. Inset: TEM image of monolayer of MNPs. Reproduced with permission from Reference [71
]. Copyright 2017, American Chemical Society. (b) Magnetically guided, bacterially driven RBC microswimmers for active drug delivery. Reproduced with permission from Reference [72
]. Copyright 2018, The Authors, exclusive licensee American Association for the Advancement of Science.