A self-healing micellar hydrogel system for controlled release of caffeic acid phenethyl ester and durable inhibition of prostate tumor.

Hydrogel-encapsulation allows slow and stable delivery of drugs with short half-lives, avoiding the undesired side effects of high-dose or frequent administration of drugs. We previously reported that gavage or injection of caffeic acid phenethyl ester (CAPE) at 10-15 mg/kg, 2-3 times per week effectively repressed the tumor growth of human prostate xenografts in nude mice. However, daily oral or injectable delivery of CAPE in prostate cancer (PCa) patients may be impractical due to forgetfulness, physical limitations, or treatment fatigue.

An antioxidative injectable chitosan hydrogel based on tannic acid modified dialdehyde polyurethane nano-crosslinker targeting RIPK1 to regulate neuroinflammation for amelioration of Parkinson's disease.

Parkinson's disease (PD) is one of the most common age-related neurodegenerative diseases. Currently, the treatment of PD is mainly based on surgery and medication, and there is a pressing necessity to develop a new generation of strategies incorporating biomaterials for treating PD. Herein, an antioxidative injectable chitosan hydrogel crosslinked with tannic acid-modified dialdehyde polyurethane nanoparticles (TA@DAP) to target RIPK1 is produced for ameliorating PD.

Smart hydrogels for in situ tissue drug delivery.

The application of smart hydrogels has become a booming research frontier in biomedical engineering. With the development of intelligent drug delivery systems, various biomimetic and biodegradable hydrogels are employed for localized drug delivery to tissues in the preclinical applications. These advanced materials are designed to match the diverse environmental and functional requirements of various tissue types and organs.

Chitosan catechol-tannic acid composite hydrogel and cryogel with antimicrobial and hemostatic properties.

Hydrogels containing catechol group have received attention in the biomedical field due to their robust adhesive/cohesive capabilities, biocompatibility, and hemostatic abilities. Catechol-functionalized chitosan holds promise for preparing self-assembly hydrogels. However, issues of inefficient gelation and instability still persist in these hydrogels.

Stretchable and biodegradable chitosan-polyurethane-cellulose nanofiber composites as anisotropic materials.

Chitosan is a naturally derived biodegradable polymer with abundancy, sustainability, and ease of chemical modification. Polyurethanes are a family of elastic biocompatible polymers, and composites of polyurethanes have versatile properties and applications. Chitosan-polyurethane composites were recently developed but had insufficient strength and limited stretchability.

Gelation and the Self-Healing Behavior of the Chitosan-Catechol Hydrogel.

Mussel-inspired adhesive hydrogels have been developed in biomedical fields due to their strong adhesive property, cohesive capability, biocompatibility, and hemostatic ability. Catechol-functionalized chitosan is a potential polymer used to prepare adhesive hydrogels. However, the unique gelation mechanism and self-healing properties of catechol-grafted chitosan alone have not yet been explored.

Functionalized Cellulose Nanofibers as Crosslinkers to Produce Chitosan Self-Healing Hydrogel and Shape Memory Cryogel.

Cellulose nanofibers functionalized with multiple aldehyde group were synthesized as the crosslinker to produce composite self-healing hydrogel and shape memory cryogel from chitosan. The hydrogel possessed effective self-healing (∼100% efficiency) and shear-thinning properties. The cryogel had macroporous structure, large water absorption (>4300%), and high compressibility.

Biomimetic Strain-Stiffening in Chitosan Self-Healing Hydrogels.

The strain-stiffening and self-healing capabilities of biological tissues enable them to preserve the structures and functions from deformation and damage. However, biodegradable hydrogel materials with both of these biomimetic characteristics have not been explored. Here, a series of strain-stiffened, self-healing hydrogels are developed through dynamic imine crosslinking of semiflexible -carboxymethyl chitosan (main chain) and flexible dibenzaldehyde-terminated telechelic poly(ethylene glycol) (crosslinker).

Smart polymers for cell therapy and precision medicine.

Soft materials have been developed very rapidly in the biomedical field over the past 10 years because of advances in medical devices, cell therapy, and 3D printing for precision medicine. Smart polymers are one category of soft materials that respond to environmental changes. One typical example is the thermally-responsive polymers, which are widely used as cell carriers and in 3D printing.