A medical device for repairing a lesion in a spinal cord or in a peripheral nerve is provided. The medical device has a flexible support made of expanded polytetrafluoroethylene. Stem cells suitable for being oriented along a first growth direction or a second growth direction are at least partially embedded on the flexible support that is suitable for taking an extended configuration and a wound configuration. In the wound configuration, the flexible support is suitable for being wound around the spinal cord so that the first and second growth directions are substantially statistically parallel to a neuronal extension direction of neurons of the spinal cord. Surgical methods of treating a spinal injury involving using the medical device are also provided.

A method for making iridium oxide nanoparticles includes dissolving an iridium salt to obtain a salt-containing solution, mixing a complexing agent with the salt-containing solution to obtain a blend solution, and adding an oxidating agent to the blend solution to obtain a product mixture. A molar ratio of a complexing compound of the complexing agent to the iridium salt is controlled in a predetermined range so as to permit the product mixture to include iridium oxide nanoparticles.

An artificial tissue construct for nerve repair and regeneration includes a biocompatible and biodegradable nerve guidance matrix comprising a plurality of biopolymers that include chitosan, gelatin, collagen and hyaluronic acid. A cross-linker includes glutaraldehyde. The nerve guidance matrix is formed as a three-dimensional scaffold polyelectrolyte complex (PEC). A subconfluent and grown monolayer of at least one of human mesenchymal stem cells, mesenchymal stem cells, differentiated Schwann cells and neuronal cells is on the biocompatible and biodegradable nerve guidance matrix for direct implantation or delivery. A method of making the artificial tissue construct is disclosed.

Magneto-responsive properties are traditionally imparted to scaffold systems via integration of iron oxide-based magnetic nanoparticles (MNPs), yet poor understanding of long-term MNP toxicity presents a significant translational challenge. Given the demonstrated iron-binding capacity of silk fibroin (SF), passive chelation of ferric iron ions is explored herein as an alternative, MNP-free approach for magnetic functionalization of silk fibroin (SF)-based biomaterials. SF microfibers treated with aqueous ferric chloride (FeCl.sub.3) exhibit significantly increased iron content relative to the nascent protein.

A nerve guidance conduit includes one or more guidance channels formed as porous polymeric structures. The guidance channels are within an outer tubular structure that includes randomly-oriented nanofibers. The guidance channels may have electrospun nanofibers on their inner and outer surfaces in a parallel alignment with the guidance channels. Such aligned nanofibers may also be present on the inner surface of the outer tubular structure. The outer surfaces of the guidance channels and the inner surface of the tubular structure define additional guidance channels. Such a nerve guidance conduit provides augmented surface areas for providing directional guidance and enhancing peripheral nerve regeneration. The structure also has the mechanical and nutrient transport requirements required over long regeneration periods.

An implantable hydrogel precursor composition can include: a cross-linkable polymer matrix that is biocompatible; and a plurality of polymer particles in the cross-linkable polymer matrix. The cross-linkable polymer matrix can include a cross-linkable hyaluronic acid polymer that has cross-linkable functional groups. The hyaluronic acid polymer can be a methacrylated hyaluronic acid polymer. The methacrylated hyaluronic acid polymer can have a molecular weight from about 500 kDa to about 1.8 MDa. The polymer particles can include a cross-linked hyaluronic acid. The cross-linkable polymer matrix having the polymer particles has a yield stress. The cross-linkable polymer matrix having the polymer particles has shape retention at physiological temperatures. The composition can include live cells in the cross-linkable polymer matrix. The composition can include a biologically active agent in the cross-linkable polymer matrix.

The present disclosure pertains to membranous tissue grafts comprising one or more pre-made attachment points. The one or more pre-made attachment points may include pre-made markings and/or pre-made suture holes. The membranous tissue grafts can be in the form of a tube. The membranous tissue grafts can also be rectangular in shape and can be used in a nerve repair by wrapping the severed or damaged nerve. In some embodiments, the membranous tissue grafts are suitable for repairing severed nerves that have a short gap or no gap with a gap of less than 5 mm between the severed stumps. Accordingly, methods are provided for repairing a damaged or severed nerve by implanting the membranous tissue grafts on to the damaged or severed nerve.

A system and methods for producing a structure including a plurality of fibers is provided. The system includes a polymer collector having a predefined pattern, wherein the collector is charged at a first polarity, and a spinneret configured to dispense a polymer, wherein the spinneret is charged at a second polarity substantially opposite the first polarity such that polymer dispensed from the spinneret forms a plurality of fibers on the predefined pattern of the fiber collector.

Tissue scaffolds for neural tissue growth have a plurality of microchannels disposed within a sheath. Each microchannel comprises a porous wall having a thickness of about 100 m that is formed from a biocompatible and biodegradable material comprising a polyester polymer. The polyester polymer may be polycaprolactone, poly(lactic-co-glycolic acid) polymer, and combinations thereof. The tissue scaffolds have high open volume % enabling superior (linear and high fidelity) neural tissue growth, while minimizing inflammation near the site of implantation in vivo. In other aspects, methods of making such tissue scaffolds are provided. Such a method may include mixing a reduced particle size porogen with a polymeric precursor solution. The material is cast onto a template and then can be processed, including assembly in a sheath and removal of the porogen, to form a tissue scaffold having a plurality of porous microchannels.

A composite nerve conduit comprising an elongated body comprising one or more hollow elongated internal channels for guiding and promoting nerve regeneration. The conduit is a three-dimensional scaffold comprising a crosslinked hybrid/composite matrix of collagen and soy protein isolate having improved mechanical and biocompatibility properties. Methods of using the conduit for promoting nerve regeneration at a site of neural tissue damage by bridging wounded, severed, or damaged nerve sections in a peripheral and/or central nervous system. Methods of fabricating composite neural conduits are also disclosed.