Femtosecond laser direct writing functional microstructures on recombinant human Ⅲ-Type collagen with sub-micron morphological feature

Femtosecond laser direct writing based on multiphoton polymerization exhibits a powerful ability for additive manufacturing of micro- and nano- structures, possessing a number of promising applications in many areas, especially in biology and cell cultures due to the biocompatibility, high-precision and noncontact fabrication route. Cutting-edge biological applications often entail the renew materials, therefore exploiting the microstructure manufacturing of them is necessary for creating reliable solutions. In this study, we report, to the best of our knowledge, the first successful fabrication of recombinant human Ⅲ-Type collagen (RHC III chain) microstructure with sub-micron morphological feature using femtosecond laser multiphoton polymerization. By adjusting the laser power and scanning speed, a lateral fabrication resolution of ∼468.1 nm for RHC III chain is obtained in 2D line voxels, which shows high-precision manufacturing capability of femtosecond laser direct writing. In the meantime, the 2D and quasi-3D microstructures on RHC III chain are constructed to demonstrate the arbitrary fabrication ability. Furthermore, an innovative fusion has come to our work that promises to significantly achieve the interdisciplinary combination of RHC III chain material and optics. Functional optical devices including grating, microlens and Fresnel zone plate constructed of RHC III chains exhibit not only favorable optical performance but also remarkable biological stability without changing with the surrounding environment. Besides, microstructural scaffolds based-RHC III chain demonstrates cells or neuros can be increased or gathered on the scaffold through the cell culture experiment. This study presents a novel approach for engineering complex microstructures and micropatterns in RHC III chains with sub-micrometer topological features, achieving the combination of optics and biology, which promotes the development of biophotonics and tissue repair.