The present disclosure provides a method of fabricating curvature-defined (C-D) or shape-defined (S-D) concave and convex polydimethylsiloxane (PDMS) surfaces and a method of fabricating C-D or S-D convex and concave gel surfaces for use in cell and tissue culturing and in other surface and interface applications, and provides a method of using C-D or S-D convex and concave surfaces with varying curvatures to direct cell attachment, spreading, and migration.

A flowable birth tissue composition fabricated from birth tissue is provided. Methods of processing a mammal's placental tissue to form a flowable birth tissue composition are provided. Various methods of treatment and uses are also provided.

A method of preparing a porous protein scaffold for supporting the growth of biological tissue is described. The method comprises: providing an oil-in water emulsion comprising oil droplets dispersed in a continuous phase comprising a pH-buffered aqueous protein solution, wherein the oil-in-water emulsion comprises a non-ionic surfactant in an amount of 0.01 to 10 volume % of the total volume of the oil phase in the oil-in-water emulsion; gelling the protein around the oil droplets, such as by enzymatic activity or by non-enzymatic activity chemical reaction or by thermally controlled gelation; and removing the oil droplets from the continuous phase. A porous protein scaffold and its uses are also described.

The present invention relates to preparation and use of nanocellulose fibrils or crystals such as disintegrated bacterial nanocellulose, tunicate-derived nanocellulose, or plant-derived nanocellulose, together with carbon nanotubes, as a biocompatible and conductive ink for 3D printing of electrically conductive patterns. Biocompatible conductive bioinks described in this invention were printed in the form of connected lines onto wet or dried nanocellulose films, bacterial cellulose membrane, or tunicate decellularized tissue. The devices were biocompatible and showed excellent mechanical properties and good electrical conductivity through printed lines (3.8.Math.10.sup.−1 S cm.sup.−1). Such scaffolds were used to culture neural cells. Neural cells attached selectively on the printed pattern and formed connective networks. The devices prepared by this invention are suited as bioassays to screen drugs against neurodegenerative diseases such as Alzheimer's and Parkinson's, study brain function, and/or be used to link the human brain with electronic and/or communication devices. They can also be implanted to replace neural tissue or stimulate guiding of neural cells. They can also be used to stimulate the heart by using electrical signaling or to repair myocardial infarction and/or damage related thereto.

A cell culture substrate comprising a substrate having a coating of a plurality of amine functionalized nanoparticles is disclosed. In one embodiment, the amine functionalized nanoparticle is a polymer of an acrylamide monomer, a cross-linker and an amine monomer. There is also provided a method of making the cell culture substrate either by drying the amine functionalized nanoparticles when spread onto the said substrate or by covalent linkages of the substrate with thiol terminated nanoparticles. In addition, there is provided a method of culturing stem cells on the cell culture substrate having a coating of a plurality of the amine functionalized nanoparticles thereon.

A method is disclosed for coating and patterning hydrogels in order to modify surface properties. The method exploits the water content of the hydrogel and the hydrophobicity of the reaction solvent to create a thin oxide adhesion layer on the hydrogel surface. This oxide adhesion layer enables rapid transformation of the hydrophilic, cell non-adhesive hydrogel into either a highly hydrophobic or a cell-adhesive hydrogel by reaction with an alkylphosphonic acid or an α,ω-diphosphonoalkane, respectively. Also disclosed are coated, patterned hydrogels and constructs comprising the coated, patterned hydrogels.

The present disclosure relates to a biocompatible, in vitro probe system. The probe system may have a substrate and a culture well supported on the substrate. The culture well defines a three-dimensional volume for containing in vitro cultures of electroactive cells. The probe system has at least one probe subsystem supported on the substrate. The probe subsystem has at least one probe having an array of electrodes, with the probe being disposed within the culture well for in vitro electrically communicating with the electroactive cells. The probe subsystem is adapted to be interfaced to an external instrumentation/recording device.

A two-layer gradient coating article is provided that is operable to cause selective adhesion and directional migration of endothelial cells. The first layer includes cell-resisting polymers that repels cells, the second layer includes one layer of peptides that has affinity to and binds specifically to endothelial cells. Furthermore, the peptides are distributed in a gradient, in which attached ECs migrate towards the direction of increased concentration, thus enriching the ECs to a desired locus. The combination of a cell-repelling layer and a graded affinity peptide produces a unique result of selective adhesion, directional migration, thus local enrichment of endothelial cells. A method for using such gradient coating article and its potential use in treating cardiovascular diseases are also provided. The invention provides an inexpensive, stable and effective means for attracting ECs to desirable locations.

Methods to form a surface coating and surface pattern, which are based on adsorption of hydrocarbon chains that can be used with imaging optics to visualize macrophage fusion and multinucleated giant cell formation with living specimens are described.

The present invention relates to preparation and use of biocompatible and electrically conductive 3D hydrogels comprising nanocellulose fibrils, such as disintegrated bacterial nanocellulose, plant derived nanocellulose, tunicate derived nanocellulose, or algae derived nanocellulose, together with carbon nanotubes or graphene oxide, as a biocompatible and conductive 3D hydrogel for diagnostics and intervention to mimic or restore tissue and organ function. Biocompatible conductive 3D hydrogels described in this invention can be extruded, casted or injected. The 3D hydrogels described in this invention are cohesive 3D structures and provide electrical conductivity in wet form. 3D hydrogels described in this invention can be further crosslinked using divalent ions such as Calcium ions which improve mechanical stability. Such crosslinking can take place in an animal or human body in a physiological environment after injection into the tissue. 3D hydrogels are biocompatible and show preferable mechanical properties and electrical conductivity through printed lines (4.10.sup.1 S cm.sup.1). The 3D hydrogels prepared by this invention are suited as bioassays to screen drugs against neurodegenerative diseases such as Alzheimer's and Parkinson's, study brain function, and/or be used to link the human brain with electronic and/or communication devices. They can also be injected to replace neural tissue or stimulate guiding of neural cells. They can also be used to inject into the heart and stimulate the heart by using electrical signaling or to repair myocardial infarction.