The invention is related to a cost-effective method for making a silicone hydrogel contact lens having a crosslinked hydrophilic coating thereon. A method of the invention involves autoclaving, in a sealed lens package, a silicone hydrogel contact lens having a base coating of polyacrylic acid thereon in an aqueous solution in the presence of a water-soluble, crosslinkable hydrophilic polymeric material having epoxide groups, for a period of time sufficient to covalently attach the crosslinkable hydrophilic polymeric material onto the surface of the silicone hydrogel contact lens through covalent linkages each formed between one epoxide group and one of the carboxyl groups on and/or near the surface of the silicone hydrogel contact lens.

The present invention relates to silicone hydrogels exhibiting desired combinations of physical and mechanical properties, formed from a reactive monomer mixture comprising at least one N-alkyl methacrylamide, and at least one silicone-containing component. These silicone hydrogels may also contain hydrophilic components, crosslinking agents and toughening monomers. These silicone hydrogels are useful in preparing biomedical devices, ophthalmic lenses, and contact lenses.

A novel cutting-edge structure and method and apparatus for manufacturing the cutting-edge structure is provided. The cutting-edge structure is comprised of naturally derived or renewable material at greater than 50% by volume fraction. In one embodiment, the naturally derived material is a cellulose nanostructure such as a cellulose nanocrystal. The cellulose nanocrystal is processed using a base or mold structure to provide a cutting edge of any shape such as linear or circular edge structures. The process includes dual cure steps to produce an optimal cutting-edge structure without shrinkage. The formed cutting-edge structure can be utilized as a razor blade as it is formed with very sharp tip and edge suitable for cutting hair. The base structure can form one or more cutting-edge structures simultaneously.

Described herein are apparatuses, systems, and methods for fabricating tissue constructs, such as by fabricating perfusable tissue constructs by embedding a sacrificial material into a composite matrix yield stress support bath. A composite matrix bath can include a microgel filler and a hydrogel precursor. An extrusion tip can be used for embedded printing of perfusable tissue constructs by disposing sacrificial material into the composite matrix bath while the extrusion tip travels along a predefined course through the composite matrix bath. This sacrificial material can be the printed tissue construct or can be removed to render the matrix bath a perfusable tissue construct. The composite matrix bath can include acellular or cell-laden hydrogels. The sacrificial material can include a salt and a physiological buffer or a non-cytotoxic porogen material. The hydrogel precursor can include at least one of gellan and gelatin. Cross-linking can be carried out chemically, thermally, enzymatically, or physically.

A vascular structure-containing large-scale biological tissue and a construction method thereof. In the existing three-dimensional cell culture, it is contradictory for the elastic modulus of the scaffold material in ensuring structural stability and biocompatibility, and the vascular structure is required to provide channels for nutrient exchange when a large-scale structure is prepared. A cell-laden matrix material is poured into a hollow scaffold serving as a supporting scaffold. The overall stability of the scaffold structure can be ensured by regulating the mechanical properties of the supporting scaffold, thereby resolving the contradiction in ensuring structural stability and biocompatibility for the mechanical properties of the scaffold material in the conventional three-dimensional cell culture. A coaxially printing outer material contains a thermosensitive material. The removal of the outer thermosensitive material can increase the porosity of the vascular walls, and further increase the diffusion in the hollow vascular ducts.

A method of three-dimensional (3D) printing includes applying a solution to a channel. The solution includes a plurality of anisotropic particles suspending in the solution. Acoustic waves are applied to the channel. The frequency of the acoustic waves is configured to organize the plurality of anisotropic particles into one or more columns of organized anisotropic particles. The channel is connected to a printhead and a waste outlet. The solution comprising the one or more columns of organized anisotropic particles is deposited on a substrate via the printhead outlet.

A method and device for fabricating vascular networks in for tissue engineering. The vascular network is embedded in a porous scaffold and is created from a sacrificial wax template, according to one embodiment. A extrusion-based three dimensional printer is used to create the template, wherein the printer utilizes an extruder incorporating a mixer to maintain the consistency of the extrudate.

The present disclosure provides methods for freeform extrusion-based additive manufacturing via a robotic arm. In specific aspects, methods are particularly provided for minimally invasive, intracorporeal three-dimensional printing of biocompatible materials. An end effector of a robotic arm includes a sharp member and a reservoir filled with a printing material. The provided method may include piercing a substrate with the sharp member. A bulb or microbolus of material may be extruded beneath the substrate surface to act as an anchor. The end effector may be manipulated to extrude biomaterial along a printing path. Periodically along the printing path, the sharp member is used to pierce the substrate surface create additional respective anchors. In some instances, the method may terminate after extruding material to form a single layer construct. In other instances, the method includes forming one or more layers on top of the initial base layer anchored to the substrate.

Described herein are apparatuses, systems, and methods for fabricating tissue constructs, such as by fabricating perfusable tissue constructs by embedding a sacrificial material into a composite matrix yield stress support bath. A composite matrix bath can include a microgel filler and a hydrogel precursor. An extrusion tip can be used for embedded printing of perfusable tissue constructs by disposing sacrificial material into the composite matrix bath while the extrusion tip travels along a predefined course through the composite matrix bath. This sacrificial material can be the printed tissue construct or can be removed to render the matrix bath a perfusable tissue construct. The composite matrix bath can include acellular or cell-laden hydrogels. The sacrificial material can include a salt and a physiological buffer or a non-cytotoxic porogen material. The hydrogel precursor can include at least one of gellan and gelatin. Cross-linking can be carried out chemically, thermally, enzymatically, or physically.

Provided are live, artificial, skin substitute products and methods of making and using the same, such as for wound treatment and compound testing, including compound testing for efficacy, toxicity, penetration, irritation and/or metabolism testing of drug candidates or compositions such as cosmetics.