Functionalizing intraocular microrobots with surface coatings

Microrobots that can navigate bodily fluids will enable localized sensing and targeted drug delivery in parts of the body that are currently inaccessible or too invasive to access. Microrobots are typically envisioned as miniature mechatronic systems that utilize MEMS technology to incorporate sensing and actuation onboard. This paper presents a simpler alternative approach for the development of biomicrorobots consisting of magnetic platforms and functional coatings. Luminescence dyes immobilized in coatings can be excited and read wirelessly to detect analytes or physical properties. Drug coatings can be used for diffusion-based delivery, and may provide more efficient therapy than microsystems containing pumps, as diffusion dominates over advection at the microscale. Oxygen sensing for diagnosis in the eye and drug therapy for retinal vein occlusions are presented as example applications.