Femto‐second laser‐based free‐writing of complex protein microstructures and micropatterns, with sub‐micrometer features and controllability over voxel dimension, morphology, and porosity, is reported. Protein voxels including lines, spots, and micropillars are fabricated. Laser power, exposure time, z‐position, protein and photosensitizer concentrations, but not scanning speed, are important controlling parameters. A lateral fabrication resolution of ≈200 nm is demonstrated in 2D line voxels. 3D spot voxels are ellipsoids with 400 nm lateral and 1.5 μm axial dimensions. An ascending z‐stack scanning method to verify the theoretical axial optical resolution, delineate and enhance the axial fabrication resolution of 3D structures, including square prism and cylinder micropillars, is also reported. The micropillar array presents a simple “write‐and‐seed” and table platform for cell niche studies. Fibroblasts attach to, grow on, and express adhesion to molecules on micropillar arrays without the need of matrix coating. They exhibit a more “3D” morphology comparing with that in 2D monolayer cultures and physiological functions such as matrix deposition. This work presents an important milestone in engineering complex protein microstructures and micropatterns with sub‐micrometer topological features to mimic the native matrix niche for cell‐matrix interaction studies.

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The generation of a flexible printed circuit board on polymer fabrics has been a challenge over the last decade. In this work, a copper pattern was obtained on a soft substrate of filter paper/polyacrylonitrile (FP/PAN) film, where the filter paper was commercially available. The pattern of Ag particles was first produced on an Ag+-doped FP/PAN composite film, followed by electroless plating of copper using the metal silver particles as seeds. The in situ reduction of silver particles and the formation of the silver agglomeration pattern were induced by laser irradiation technology on the FP/PAN/AgNO3 composite film. A variety of characterizations indicated that the resultant copper deposition was uniform, with good conductivity properties.

Abstract Antistatic fibers or conductive fibers can be obtained from formation of a metal conductive layer, for example silver, on the surface of polymeric fibers through a redox reaction. However, in the process of fabricating silver-polymer conductive fibers, the binding force between silver and the polymeric fiber matrix is too weak and the poor weather resistance greatly affects the performance of the conductive fibers. This work aims to synthesize composite conductive layers of polyaniline (PANi)-silver coated on polyester fibers to prepare conductive polymeric fibers, in order to improve the combining ability between the conductive layers and the fiber matrix. The morphology, thermostability, mechanical properties, washing resistance and corrosion resistance of the resultant fibers obtained from different synthesis conditions were characterized. Batch experimental results showed that the concentration of the reagent and the reaction time could affect the resistance of the PANi-silver coated conductive fibers. The results also demonstrated that the PANi-silver composite conductive fibers have better properties than those of the silver-polymer conductive fibers.