Liquid-Phase Integrated 3D Printed Biological Lenses for Lamellar Corneal Substitute.

Compared to traditional biological lenses that are used to correct optical systems, such as contact lenses, vision correction surgery, and corneal and lens replacement, 3D printed biological lenses offer a customizable solutions. However, the layer-by-layer principle of 3D printing leads to a staircase effect, which cannot meet the critical requirements of surface quality during the manufacturing process of biological lens, particularly with soft materials. Here, a liquid-phase printing strategy and a surface tension-dependent (STD) post-processing method are proposed that use the surface tension of the liquid to reconstruct the air-liquid interface. This eliminates the staircase effect caused by the stacking of units during 3D printing. The coordinates of integrated printing enable high-accuracy shape control of soft materials. Using a typical biological lens as an example, this method improves the surface quality of printed lamellar corneal substitutes (LCS) from ±20.0 to ±0.2 µm and reduces thickness feature size from ±500 to ±150 µm. This approach can match human cornea curvature and thickness, achieving ≈85% visible light transmittance and biocompatibility. Liquid-phase 3D printed biological lenses outperform molded ones in animal experiments. This method can advance artificial biological lens printing research and holds promise for future clinical applications.