Tyrosinase-Modified UHMW SELP Polymers as Wet and Underwater Adhesives to Achieve Multi-interface Adhesion.

The presence of a hydration layer in humid and underwater environments challenges adhesive-substrate interactions and prevents effective bonding, which has become a significant obstacle to the development of adhesives in the industrial and biomedical fields. In this study, ultrahigh-molecular-weight (UHMW) silk-elastin-like proteins (SELP) with 3,4-dihydroxyphenylalanine (DOPA) converted from tyrosine residues by tyrosinase exhibited excellent adhesive properties on different interfaces, such as glass, aluminum, wood, polypropylene sheets, and pigskin, under both dry and wet conditions. Additionally, by incorporating trace amounts of cross-linking agents like Fe, NaIO, and tris(hydroxymethyl) phosphine (THP), the mussel-inspired adhesives maintained a stable and excellent adhesion, broadening the conditions of application.

Low-Temperature Extrusion of Waterborne Polyurethane-Polycaprolactone Composites for Multi-Material Bioprinting of Engineered Elastic Cartilage.

3D bioprinting of elastic cartilage tissues that are mechanically and structurally comparable to their native counterparts, while exhibiting favorable cellular behavior, is an unmet challenge. A practical solution for this problem is the multi-material bioprinting of thermoplastic polymers and cell-laden hydrogels using multiple nozzles. However, the processing of thermoplastic polymers requires high temperatures, which can damage hydrogel-encapsulated cells.

A potential bilayer skin substitute based on electrospun silk-elastin-like protein nanofiber membrane covered with bacterial cellulose.

Skin substitutes are designed to promote wound healing by replacing extracellular matrix. Silk-elastin-like protein is a renewable extracellular matrix-like material that integrated the advantages of silk and elastin-like protein. In this study, electrospun silk-elastin-like protein (SELP) nanofiber membrane covered with bacterial cellulose (BC) was created as a potential skin substitute to mimic gradient structure of epidermis and dermis of skin.

A novel photocurable pullulan-based bioink for digital light processing 3D printing.

Digital light processing has significant advantages, such as high repeatability, low failure rate, and no extrusion shear force. To make it possible to print complex structures with high resolution, the consecutive development of photocurable ink materials is indispensable. In this work, photo-functionalized pullulan (Pul-NB) was prepared by introducing norbornene groups into pullulan chains, and an ink material suitable for photocurable printing was prepared by thiol-ene click reaction.

Laccase-mediated formation of hydrogels based on silk-elastin-like protein polymers with ultra-high molecular weight.

As artificial extracellular matrix-like materials, silk-elastin-like protein (SELP) hydrogels, with excellent mechanical properties, high tunability, favorable biocompatibility, and controlled degradability, have become an important candidate in biomedical materials. In this study, SELP is composed of silk-like (GAGAGS) and elastin-like (GXGVP) tandem repeats, in which X residues are set as tyrosine and lysine. Furthermore, SELP polymers are prepared via SpyTag/SpyCatcher.

Ultra-high molecular weight pullulan-based material with high deformability and shape-memory properties.

Most shape-memory polymers (SMPs) are derived from petroleum feedstocks, which have limitations due to their challenging manufacturing process. Accordingly, herein, a novel SMP based on microbially produced ultrahigh-molecular-weight (UHMW) pullulan was developed. UHMW pullulan cross-linked with 1,4-butanediol diglycidyl ether was wet-spun into fibers with high stretchability (1365 % strain) and excellent shape-memory properties.

Polylysine-decorated macroporous microcarriers laden with adipose-derived stem cells promote nerve regeneration in vivo.

Cell transplantation is an effective strategy to improve the repair effect of nerve guide conduits (NGCs). However, problems such as low loading efficiency and cell anoikis undermine the outcomes. Microcarriers are efficient 3D cell culture scaffolds, which can also prevent cell anoikis by providing substrate for adhesion during transplantation.

Hierarchical macro-microporous WPU-ECM scaffolds combined with Microfracture Promote Articular Cartilage Regeneration in Rabbits.

Tissue engineering provides a promising avenue for treating cartilage defects. However, great challenges remain in the development of structurally and functionally optimized scaffolds for cartilage repair and regeneration. In this study, decellularized cartilage extracellular matrix (ECM) and waterborne polyurethane (WPU) were employed to construct WPU and WPU-ECM scaffolds by water-based 3D printing using low-temperature deposition manufacturing (LDM) system, which combines rapid deposition manufacturing with phase separation techniques.

Design and characterization of plasticized bacterial cellulose/waterborne polyurethane composite with antibacterial function for nasal stenting.

A nasal stent capable of preventing adhesions and inflammation is of great value in treating nasal diseases. In order to solve the problems of tissue adhesion and inflammation response, we prepared plasticized bacterial cellulose (BCG) and waterborne polyurethane (WPU) composite with antibacterial function used as a novel nasal stent. The gelation behavior of BCG could contribute to protecting the paranasal sinus mucosa; meanwhile, the WPU with improved mechanical property was aimed at supporting the narrow nasal cavity.

A novel waterborne polyurethane with biodegradability and high flexibility for 3D printing.

Three-dimensional (3D) printing provides a new approach of fabricating implantable products because it permits a flexible manner to extrude complex and customized shapes of the tissue scaffolds. Compared with other printable biomaterials, the polyurethane elastomer has several merits, including excellent mechanical properties and good biocompatibility. However, some intrinsic behavior, especially its high melting point and slow rate of degradation, hampered its application in 3D printed tissue engineering.

Preparation of aminoalkyl-grafted bacterial cellulose membranes with improved antimicrobial properties for biomedical applications.

Bacterial cellulose (BC) membranes display special properties and structures, thus attracting much attention in application in the biomedical areas, for example, as implants for bone or cartilage tissue engineering, as substitutes for skin repairing, and as supports for controlled drug delivery. However, native BC lacks the activity to inhibit bacteria growth on its surface, which limits its applications in biomedical fields. There have been reports on chemical modification of BC membranes to endow them with antimicrobial properties needed for some special biomedical applications.

A biocompatible bacterial cellulose/tannic acid composite with antibacterial and anti-biofilm activities for biomedical applications.

Biofilm-associated infections are in a high rate of recurrence and biofilms show formidable resistance to current antibiotics, making them a growing challenge in biomedical field. In this study, a biocompatible composite was developed by incorporating tannic acid (TA) and MgCl to bacterial cellulose (BC) for antimicrobial and anti-biofilm purposes. The morphology was investigated by scanning electron microscopy (SEM), and chemical structure were characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectra (XPS).

PCL-MECM-Based Hydrogel Hybrid Scaffolds and Meniscal Fibrochondrocytes Promote Whole Meniscus Regeneration in a Rabbit Meniscectomy Model.

Regeneration of an injured meniscus continues to be a scientific challenge due to its poor self-healing potential. Tissue engineering provides an avenue for regenerating a severely damaged meniscus. In this study, we first investigated the superiority of five concentrations (0%, 0.

An ultrasound-controllable release system based on waterborne polyurethane/chitosan membrane for implantable enhanced anticancer therapy.

Anti-relapse therapy after surgery plays a critical role in cancer therapy. New strategies maximizing the delivery of drugs to tumor cells while reducing toxic side effects on normal tissues and organs are still urgently required. In order to solve the problems of the poor delivery and inadequate distribution of cytotoxic chemotherapeutic drugs in the clinical application, an ultrasound-controllable and implantable release-system that utilized waterborne polyurethane (WPU) and chitosan (CS) composite membrane as drug carrier with wide flexible loading capacity for doxorubicin (DOX) was described in present work.

Enhanced Neurite Outgrowth on a Multiblock Conductive Nerve Scaffold with Self-Powered Electrical Stimulation.

Electrical stimulation (ES) is widely applied to promote nerve regeneration. Currently, metal needles are used to exert external ES, which may cause pain and risk of infection. In this work, a multiblock conductive nerve scaffold with self-powered ES by the consumption of glucose and oxygen is prepared.

Recyclable Fully Biobased Chitosan Adsorbents Spray-Dried in One Pot to Microscopic Size and Enhanced Adsorption Capacity.

A facile one-pot spray-drying process was developed for fabrication and in situ crosslinking of chitosan microspheres to improve the adsorption capacity by microscopic design. A fully biobased nature was achieved by utilizing genipin (GP) as a crosslinking agent and chitosan-derived nanographene oxide (nGO) as a property tuner. The produced chitosan microspheres were further proven as powerful adsorbents for common wastewater contaminants such as anionic dyes and pharmaceutical contaminants, here modeled by methyl orange (MO) and diclofenac sodium (DCF).

Tunable chitosan hydrogels for adsorption: Property control by biobased modifiers.

A sustainable strategy to fabricate chitosan-based composite hydrogels with tunable properties and controllable adsorption capacity of trace pharmaceuticals was demonstrated. Two biobased modifiers were utilized to tune the properties, nano-graphene oxide (nGO) derived from chitosan via microwave-assisted carbonization and oxidation, and genipin as the crosslinking agent. An increase in genipin content facilitated an increase in the degree of crosslinking as shown by improved storage modulus and decreased swelling ratio.