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Self-powered information encoding devices (IEDs) have drawn considerable interest owing to their capability to process information without batteries. Next-generation IEDs should be reprogrammable, self-healing, and wearable to satisfy the emerging requirements for multifunctional IEDs; however, such devices have not been demonstrated. Herein, an integrated triboelectric nanogenerator-based IED with the aforementioned features was developed based on the designed light-responsive high-permittivity poly(sebacoyl diglyceride

Long-segment defects remain a major problem in clinical treatment of tubular tissue reconstruction. The design of tubular scaffold with desired structure and functional properties suitable for tubular tissue regeneration remains a great challenge in regenerative medicine. Here, we present a reliable method to rapidly fabricate tissue- engineered tubular scaffold with hierarchical structure via 4-axis printing system. The fabrication process can be adapted to various biomaterials including hydrogels, thermoplastic materials and thermosetting materials. Using polycaprolactone (PCL) as an example, we successfully fabricated the scaffolds with tunable tubular architecture, controllable mesh structure, radial elasticity, good flexibility, and luminal patency. As a preliminary demonstration of the applications of this technology, we prepared a hybrid tubular scaffold via the combination of the 4-axis printed elastic poly(glycerol sebacate) (PGS) bio-spring and electrospun gelatin nanofibers. The scaffolds seeded with chondrocytes formed tubular mature cartilage-like tissue both via in vitro culture and subcutaneous implantation in the nude mouse, which showed great potential for tracheal cartilage reconstruction.

One of the pivotal factors that limits the clinical applications of tissue engineering is the inability to create complex three-dimensional (3D) tissues due to the lack of a long-range mass transport capability. Here we present a simple versatile strategy to fabricate perfusable and permeable hierarchical microchannel-networks (PHMs) via the combination of one-pot 3D printed sacrificial caramel templates and polymer coating with integrated phase separation. The patterned PHMs possess a biomimetic three level vascular structure including a custom-made scalable 3D framework, interconnected microchannels and permeable walls with controllable micropores. The fabrication process can be adapted to various polymers and integrated with diverse matrices including hydrogels, particle leached porous scaffolds, electrospun nanofibers, and bacterial cellulose. We demonstrated the power of PHMs to facilitate mass exchange in tissue engineering constructs by showing that the PHMs could maintain the metabolic functions of heart cells in vitro, facilitate in vivo angiogenesis and tissue integration, and efficiently treat myocardial infarction.

Elastomers are essential for stretchable electronics, which have become more and more important in bio-integrated devices. To ensure high compliance with the application environment, elastomers are expected to resist, and even self-repair, mechanical damage, while being friendly to the human body. Herein, inspired by peptidoglycan, we designed the first room-temperature autonomous self-healing biodegradable and biocompatible elastomers, poly(sebacoyl 1,6-hexamethylenedicarbamate diglyceride) (PSeHCD) elastomers. The unique structure including alternating ester-urethane moieties and bionic hybrid crosslinking endowed PSeHCD elastomers superior properties including ultrafast self-healing, tunable biomimetic mechanical properties, facile reprocessability, as well as good biocompatibility and biodegradability. The potential of the PSeHCD elastomers was demonstrated as a super-fast self-healing stretchable conductor (21 s) and motion sensor (2 min). This work provides a new design and synthetic principle of elastomers for applications in bio-integrated electronics., Superfast autonomous self-healing biocompatible and biodegradable elastomers were developed based on unique alternating ester-urethane moieties and bionic hybrid crosslinking networks, showing great potential for stretchable electronics.

Cartilage defect repair remains a great clinical challenge due to the limited self-regeneration capacity of cartilage tissue. Surgical treatment of injured cartilage is rather difficult due to the narrow space in the articular cavity and irregular defect area. Herein, we designed and fabricated chondrogenic and physiological-temperature-triggered shape-memory ternary scaffolds for cell-free cartilage repair, where the poly (glycerol sebacate) (PGS) networks ensured elasticity and shape recovery, crystallized poly (1,3-propylene sebacate) (PPS) acted as switchable phase, and immobilized bioactive kartogenin (KGN) endowed the scaffolds with chondrogenic capacity. The resultant scaffolds exhibited shape-memory properties with shape-memory fixed ratio of 98% and recovered ratio of 97% at 37°C for PPS/PGS/KGN-100, indicating a good potential for minimally invasive implantation. The scaffolds gradually degraded in Dulbecco's phosphate-buffered saline and released KGN up to 12 weeks in vitro. In addition, the scaffolds promoted chondrogenic differentiation while inhibiting osteogenic differentiation of bone marrow-derived mesenchymal stem cells in a concentration-dependent manner and cartilage regeneration in full-thickness defects of rat femoropatellar groove for 12 weeks. Consequently, the PPS/PGS/KGN-100 scaffolds stimulated the formation of an overlying layer of neocartilage mimicking the characteristic architecture of native articular cartilage even in the absence of exogenous growth factors and seeded cells. This study provides much inspiration for future research on cartilage tissue engineering. STATEMENT OF SIGNIFICANCE: There are two crucial challenges for cartilage defect repair: the lack of self-regeneration capacity of cartilage tissue and difficult scaffold implantation via traditional open surgery due to space-limited joints. Herein, bioactive body-temperature-responsive shape memory scaffolds are designed to simultaneously address the challenges. The scaffolds can be readily implanted by minimally invasive approach and recover by body-temperature of patient. The integration of kartogenin endows scaffolds the bioactivity, leading to the first example of bulk shape-memory scaffolds for cell-free cartilage repair. These characteristics make the scaffolds advantageous for clinical translation. Moreover, our developed material is easy to be functionalized due to the presence of extensive free hydroxyl groups and provides a versatile platform to design diverse functional shape memory biomaterials.

This work presented a novel kind of one-dimensional multi-functional modifier for membrane materials. Cysteine modified silver nanowires (C-AgNWs) were used to modify polyvinylidene fluoride (PVDF) membranes and the comprehensive optimized properties including separation efficiency, mechanical strength and antifouling ability of PVDF membranes demonstrated that monodisperse, orientated and zwitterionic C-AgNWs were an efficient modifier for the PVDF ultrafiltration membrane. The objective of this work was to comprehensively improve the application performance of polymer materials using the special hybrid mechanism of one-dimensional nanomaterials.

Stretchable conductive fibers are key elements for next-generation flexible electronics. Most existing conductive fibers are electron-based, opaque, relatively rigid, and show a significant increase in resistance during stretching. Accordingly, soft, stretchable, and transparent ion-conductive hydrogel fibers have attracted significant attention. However, hydrogel fibers are difficult to manufacture and easy to dry and freeze, which significantly hinders their wide range of applications. Herein, organohydrogel fibers are designed to address these challenges. First, a newly designed hybrid crosslinking strategy continuously wet-spins hydrogel fibers, which are transformed into organohydrogel fibers by simple solvent replacement. The organohydrogel fibers show excellent antifreezing ( 5 months), transparency, and stretchability. The predominantly covalently crosslinked network ensures the fibers have a high dynamic mechanical stability with negligible hysteresis and creep, from which previous conductive fibers usually suffer. Accordingly, strain sensors made from the organohydrogel fibers accurately capture high-frequency (4 Hz) and high-speed (24 cm s-1 ) motion and exhibit little drift for 1000 stretch-release cycles, and are powerful for detecting rapid cyclic motions such as engine valves and are difficult to reach by previously reported conductive fibers. The organohydrogel fibers also demonstrate potential as wearable anisotropic sensors, data gloves, soft electrodes, and optical fibers.

In this work, a novel modification method was introduced to improve the antifouling property of polyvinylidene fluoride (PVDF) ultrafiltration membranes, which were prepared with a one-pot process using plasma pretreatment and graft polymerization of PVDF powder. The amphiphilic copolymer of polyvinylidene fluoride-g-polyacrylic acid (PVDF-g-PAA) present in the modified PVDF membrane was demonstrated by infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). The improved wetting ability was conducive to improve the water flux, bovine serum albumin rejection and antifouling ability of modified PVDF membranes. A totally novel pH quantitative method was employed to investigate the antifouling property based on the acid–base reaction of the amino acid residues of BSA (pollutant), according to the detected change of BSA adsorption amount on membrane surface and pore surface before and after modification, less irreversible fouling was detected in the modified PVDF membrane due to the existence of PVDF-g-PAA, and it was more convenient to remove the pollutants in the pores of modified PVDF membranes by water flushing.

Branched polyethylene glycol (PEG) was anchored onto a membrane surface by efficient covalent self-assembly to optimize the separation and antifouling properties of polyvinylidene fluoride (PVDF) ultrafiltration membranes based on its excellent hydrophilic and antifouling properties. The results showed that the surface self-assembly method could effectively improve the stability of PEG and the surface wetting ability of the PVDF membrane, and simultaneously enhanced the water flux and rejection of modified membranes. Meanwhile, the fouling results showed the anchored PEG segments on the separation interface contributed to improve the antifouling performance of the PVDF ultrafiltration membrane with significantly improved anti-adsorption capacity for bovine serum albumin (BSA) and expectant water flux recovery ratios for BSA and humic acid (HA), two typical pollutants. This paper provides a sample modification idea and demonstrated covalent self-assembly was an effective method for surface modification.