Novel SiO2 photonic crystal microspheres as inorganic pigments for structural color contact lenses

Traditional contact lenses patterns are mostly colored with organic pigments, but they suffered a pigment leakage risk after long-term wearing, which causes corneal inflammation and ulceration. To solve this issue, the structural color is applied to contact lenses because it has color and pigment free. Herein, we reported the application of SiO 2 photonic crystal microspheres in contact lenses. We successfully prepared SiO 2 photonic crystal ink with structural color and fabricated contact lenses by ink transfer printing, and these contact lenses also contain patterns and pupil areas that are the same as the traditional pigment one. In addition, in vitro cytotoxicity test, physicochemical property test, and optical property test were carried out to verify the performance of the prepared structural color lenses. All results suggested it has great potential to replace traditional organic pigment contact lenses.