Figure 4.

Use of microrobots for enhanced retention of payloads in the gastrointestinal tract. (A) Schematic illustration of in vivo operation of microrobots in mouse model. (B) Micrograph illustrating the bubble generation at the end of the microorobot responsible for locomotion. Scale bar: 20 μm. (C) Fluorescent images illustrating the gastrointestinal track retention of the dye Rhodamine 6G delivered by the chemically propelled microrobot (i: control, ii: after 6 h, and iii: after 12 h of administration. Reprinted with permission from Li et al. (2016). Copyright 2016 American Chemical Society.