Polymorphic calcium alginate microfibers assembled using programmable microfluidic field for cell regulation

Effectively guiding and accurately controlling cell adhesion and growth on the surface of specific morphological materials are key issues and hot research directions for optimizing biomaterials. Herein, novel polymorphic alginate microfibers formed through microfluidic spinning technology in a single microchip are presented. Through programming flow and reaction kinetics in microchannel other than self-modified micro-morphic channel geometry, polymorphic microfibers with curvature-adjustable morphology can be precisely tuned. Finite element (FE) simulation of the flow field (unidirectional fluid-solid coupling) proved the efficacy of the proposed control strategy. Moreover, the specific disordered-ordered cell arrangements in the linear relationship between bioinspired alginate microfibers with different curvatures and orientation angle of L929 cells, and diversified growth morphologies including oblate ellipse, star, tree and strip shapes happened on the customizable interface curvature of calcium alginate microfibers, providing a paradigm to use specific structured natural biomedical materials for cell regulation. This work represents a new design concept for manufacturing polymorphic fibrous biomedical materials through a unique marriage field of green chemistry, hydromechanics, and biomaterials, which should be very useful for guiding controllable construction of alginate materials for use in biomedical and engineering structural materials.