Black silicon as a multifunctional material for medical implants: First demonstrated use in in-vivo intraocular pressure sensing

We report the first in vivo demonstrated use of multifunctional black silicon (b-Si) on medical implants. B-Si is integrated onto the surface of a highly miniaturized sub-mm implantable intraocular pressure (IOP) sensor. This integration has significantly improved sensor signal-to-noise ratio (SNR) through the suppression of background noise as well as durability through minimized device biofouling. The incorporation of b-Si has enabled the use of a slit-lamp, the most widely used clinical ophthalmic microscope, for real-time IOP measurements on fully awake rabbits at a world-record 12-cm readout distance. Furthermore, b-Si has shown remarkable antifouling properties during a 6-month in vivo study by minimizing tissue proliferation and encapsulation on the ocular implant, promising much improved long-term implant serviceability.