The invention provides injectable, tough hydrogels that can be crosslinked in situ on demand using minimally-invasive methods, such as visible light exposure is an unmet medical challenge. Among the emerging biopolymers for tissue sealing, gelatin methacryloyl (GelMA), a naturally-derived biopolymer obtained from denatured collagen, has secured a promising role as a result of its excellent bioadhesion, biodegradation, and biocompatibility. To overcome one of the main shortcomings of GelMA, i.e., brittleness, we hybridized it using methacrylate-modified alginate (AlgMA) to impart ion-induced reversible crosslinking that can dissipate energy under strain. The hybrid GelMA-AlgMA hydrogels provide a photocrosslinkable, injectable, and adhesive platform with an excellent toughness that can be engineered using divalent cations, such as calcium. This class of novel hybrid biopolymers with more than 600% improved toughness may set the stage for durable, mechanically-resilient, and cost-effective tissue sealants in minimally invasive procedure, especially for stretchable tissues.

Hemostatic compositions including a combination of more than one hemostatic agent, and devices coated or impregnated therewith, have been developed. Nanotechnology yields hemostatic agents with large surface areas thereof, thereby increasing the hemostatic properties of the device to which they are applied. By combining more than one hemostatic agent and utilizing one or more different nanotechnology approaches to enhance the surface areas thereof, the capability of the dressing to stop bleeding is improved via more than one mechanism, and thus provides better hemostasis.

Spray-dried thrombin materials obtained from feedstock solutions comprising less than 5% by weight albumin and excluding trehalose or other excipients as well as methods of manufacturing the thrombin materials and methods of treating bleeding wounds are disclosed. The methods of use include applying reconstituted spray-dried thrombin topically to a bleeding site, optionally in conjunction with gelatin.

Film forming gel compositions, useful in creating conformable and flexible gel bandages, can be formulate from a film-forming polymer, a tackifier, and a volatile solvent. The film forming gels can also include antiseptics, cationic polymer coagulants, fillers, and other additives. The gel compositions form relatively thick films when dried on tissue, and can exhibit enhanced breathability to promote wound healing.

The present disclosure provides compositions, methods, and kits that enable the in situ growth of polymers on or within a subject. In some aspects, the tissue-active monomers, including monomers comprising macromolecules, provide abroad set of material choices for synthetic tissue barriers. In additional aspects, the compositions, methods, and kits are useful for treating or preventing a disease or disorder.

A staple cartridge comprising a tissue thickness compensator is disclosed. The tissue thickness compensator comprises an external layer and tubular elements. The tubular elements are interconnected and positioned within the external layer. The tubular elements comprise apertures defined therein and the tubular elements are configured to collapse as pressure is applied to the tissue thickness compensator by tissue during the firing motion. The apertures enable fluids from the tissue to permeate the tissue thickness compensator.

A tissue adhesive for contacting a tissue site, the tissue adhesive comprising: a mixture of natural polymers; and an activating agent enhancing the adhesive properties of the mixture of natural polymers. And a tissue adhesive for contacting a tissue site, the tissue adhesive comprising: a mixture of natural polymers; and an aqueous solution of a water soluble starch or a water soluble starch derivative which forms a gel with the addition of the mixture of natural polymers.

The present invention relates to a tissue adhesion agent having improved bio-tissue adhesiveness and bonding force by utilizing an adhesion-related gene. More specifically, a cartilage tissue adhesion composition prepared from fetal cartilage tissue-derived stem cells in which VCAN, CTGF, or EXT1 is inserted and expressed in an upregulated manner was found to show a remarkably superb adhesive force, compared to that prepared from fetal cartilage tissue-derived stem cells in which none of the genes are inserted. Accordingly, the cell composition in which the expression of VCAN, CTGF, or EXT1 is upregulated can be prepared into a tissue adhesion composition having improved bio-tissue adhesiveness and bonding force and VCAN, CTGF, or EXT1 can be provided as an additive composition for a tissue adhesion agent.

The present invention relates to a process for producing a low endotoxin alkali chitosan, and also to a process for producing low endotoxin neutral chitosan, chitosan salt and chitosan derivatives, and to the products of such processes. The process comprises contacting chitosan with an alkali solution to form a mixture and leaving the mixture for at least about 12 hours. The low endotoxin alkali chitosan may be used in the manufacture of other useful chitosan based products.

A method of producing embolic particles includes forming a master batch of embolic particles, wherein the master batch of particles includes a plurality of negatively charged loading sites. The method also includes modifying the master batch of particles to form an activated batch of particles by reacting the master patch of particles with a bridging agent. The activated batch of particles includes a plurality of activated loading sites configured to bond to a negatively charged drug.