Recent advances in biomaterials, thin film processing, and nanofabrication offer the opportunity to design electronics with novel and unique capabilities, including high mechanical stability and biodegradation, which are relevant in medical implants, environmental sensors, and wearable and disposable devices. Combining reliable electrical performance with high mechanical deformation and chemical degradation remains still challenging. This work reports temperature sensors whose material composition enables full biodegradation while the layout and ultrathin format ensure a response time of 10 ms and stable operation demonstrated by a resistance variation of less than 0.7% when the devices are crumpled, folded, and stretched up to 10%. Magnesium microstructures are encapsulated by a compostable‐certified flexible polymer which exhibits small swelling rate and a Young's modulus of about 500 MPa which approximates that of muscles and cartilage. The extension of the design from a single sensor to an array and its integration onto a fluidic device, made of the same polymer, provides routes for a smart biodegradable system for flow mapping. Proper packaging of the sensors tunes the dissolution dynamics to a few days in water while the connection to a Bluetooth module demonstrates wireless operation with 200 mK resolution prospecting application in food tracking and in medical postsurgery monitoring.

A powerful replica molding methodology to transfer on-demand functional topographies to the surface of bacterial cellulose nanofiber textures is presented. With this method, termed guided assembly-based biolithography (GAB), a surface-structured polydimethylsiloxane (PDMS) mold is introduced at the gas-liquid interface of an Acetobacter xylinum culture. Upon bacterial fermentation, the generated bacterial cellulose nanofibers are assembled in a three-dimensional network reproducing the geometric shape imposed by the mold. Additionally, GAB yields directional alignment of individual nanofibers and memory of the transferred geometrical features upon dehydration and rehydration of the substrates. Scanning electron and atomic force microscopy are used to establish the good fidelity of this facile and affordable method. Interaction of surface-structured bacterial cellulose substrates with human fibroblasts and keratinocytes illustrates the efficient control of cellular activities which are fundamental in skin wound healing and tissue regeneration. The deployment of surface-structured bacterial cellulose substrates in model animals as skin wound dressing or body implant further proves the high durability and low inflammatory response to the material over a period of 21 days, demonstrating beneficial effects of surface structure on skin regeneration.

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The micron-scale surface topography of implanted materials represents a complementary pathway, independent of the material biochemical properties, regulating the process of biological recognition by cells which mediate the inflammatory response to foreign bodies. Here we explore a rational design of surface modifications in micron range to optimize a topography comprised of a symmetrical array of hexagonal pits interfering with focal adhesion establishment and maturation. When implemented on silicones and hydrogels in vitro, the anti-adhesive topography significantly reduces the adhesion of macrophages and fibroblasts and their activation toward effectors of fibrosis. In addition, long-term interaction of the cells with anti-adhesive topographies markedly hampers cell proliferation, correlating the physical inhibition of adhesion and complete spreading with the natural progress of the cell cycle. This solution for reduction in cell adhesion can be directly integrated on the outer surface of silicone implants, as well as an additive protective conformal microstructured biocellulose layer for materials that cannot be directly microstructured. Moreover, the original geometry imposed during manufacturing of the microstructured biocellulose membranes are fully retained upon in vivo exposure, suggesting a long lasting performance of these topographical features after implantation.

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Progressive antibiotic resistance is a serious condition adding to the challenges associated with skin wound treatment, and antibacterial wound dressings with alternatives to antibiotics are urgently needed. Cellulose‐based membranes are increasingly considered as wound dressings, necessitating further functionalization steps. A bifunctional peptide, combining an antimicrobial peptide (AMP) and a cellulose binding peptide (CBP), is designed. AMPs affect bacteria via multiple modes of action, thereby reducing the evolutionary pressure selecting for antibiotic resistance. The bifunctional peptide is successfully immobilized on cellulose membranes of bacterial origin or electrospun fibers of plant‐derived cellulose, with tight control over peptide concentrations (0.2 ± 0.1 to 4.6 ± 1.6 µg mm−2). With this approach, new materials with antibacterial activity against Staphylococcus aureus (log4 reduction) and Pseudomonas aeruginosa (log1 reduction) are developed. Furthermore, membranes are cytocompatible in cultures of human fibroblasts. Additionally, a cell adhesive CBP‐RGD peptide is designed and immobilized on membranes, inducing a 2.2‐fold increased cell spreading compared to pristine cellulose. The versatile concept provides a toolbox for the functionalization of cellulose membranes of different origins and architectures with a broad choice in peptides. Functionalization in tris‐buffered saline avoids further purification steps, allowing for translational research and multiple applications outside the field of wound dressings.

Autologous epidermis grafts generated in vitro represent a promising option for the treatment of burn wounds. The procedure relies on of a sufficient number of cells harvested from healthy tissue, which are then sparsely seeded on a target surface. The time required to reconstitute a fully confluent and mature monolayer and the limited availability of cell seeds hinder the broad clinical application of this procedure. Here, a novel engineering approach to enhance the in vitro expansion of epithelial tissues is designed and experimentally validated. The method combines three independent elements supporting fast epithelialization. First, the tactical seeding of epithelial cells at high density in confined channels generated by means of magnetic silicon stencils. Second, the implementation of a curved interface along the channels, increasing the edge interface length. Third, a rationally developed and oriented anisotropic topography, in the form of gratings, aligned perpendicularly to the channels. Upon removal of the stencil, unconfined cell monolayers are free to expand and invade the open space, in a process of epithelialization that fully exploits the directional migration of epithelial collectives. As compared to sparse seeding, this approach attains an almost three times faster full epithelialization of a target surface with the same number of cells. Molecular signals triggered by cell–cell and cell–substrate contacts supported this enhanced response. In summary, we introduce a facile and scalable approach yielding fast in vitro epithelial tissue expansion with optimized yield.