An object is built by depositing a mat on a build surface and utilizing a manufacturing process to position a structure over at least a portion of the mat to define an object. The object is removed from the build surface such that a first portion of the mat removed with the object is bonded to the structure, and a second portion of the mat removed with the object is unsupported by the structure. Alternatively, an object can be built by printing a conductive material over a surface to define a structure and utilizing the conductive material as a collector to control an electric field deposition over the structure to define an object where a first portion of the deposition is bonded to the structure and a second portion of the deposition is unsupported by the structure.

A method for controlling fiber cross-alignment in a nanofiber membrane, comprising: providing a multiple segment collector in an electrospinning device including a first and second segment electrically isolated from an intermediate segment positioned between the first and second segment, collectively presenting a cylindrical structure, rotating the cylindrical structure around a longitudinal axis proximate to an electrically charged fiber emitter; electrically grounding or charging edge conductors circumferentially resident on the first and second segment, maintaining intermediate collector electrically neutral; dispensing electrospun fiber toward the collector, the fiber attaching to edge conductors and spanning the separation space between edge conductors; attracting electrospun fiber attached to the edge conductors to the surface of the cylindrical structure, forming a first fiber layer; increasing or decreasing rotation speed of the cylindrical structure to alter the angular cross-alignment relationship between aligned nanofibers in adjacent layers, the rotation speed being altered to achieve a target relational angle.

A fabrication method for a filter containing tragacanthin-polyvinyl alcohol (PVA) nanofibers includes obtaining a homogenous tragacanthin-PVA solution by obtaining a PVA solution by dissolving PVA in distilled water, and adding tragacanthin to the PVA solution. The method may further include obtaining a support layer by coating a stainless steel mesh with a thin layer of a hydrophobic polymer, coating a stainless steel mesh with the thin layer of the hydrophobic polymer comprising electrospinning a hydrophobic polymer solution onto the stainless steel mesh, and forming a tragacanthin-PVA nanofibrous web on the support layer by electrospinning the homogenous tragacanthin-PVA solution onto the support layer.

A multi-laminar electrospun nanofiber scaffold for use in repairing a defect in a tissue substrate is provided. The scaffold includes a first layer formed by a first plurality of electrospun polymeric fibers, and a second layer formed by a second plurality of electrospun polymeric fibers. The second layer is combined with the first layer. A first portion of the scaffold includes a higher density of fibers than a second portion of the scaffold, and the first portion has a higher tensile strength than the second portion. The scaffold is configured to degrade via hydrolysis after at least one of a predetermined time or an environmental condition. The scaffold is configured to be applied to the tissue substrate containing the defect, and is sufficiently flexible to facilitate application of the scaffold to uneven surfaces of the tissue substrate, and to enable movement of the scaffold by the tissue substrate.

A three-dimensional electrospun nanofiber scaffold for use in repairing a defect in a tissue substrate is provided. The three-dimensional electrospun nanofiber scaffold includes a first layer formed by a first plurality of electrospun polymeric fibers and a second layer formed by a second plurality of electrospun polymeric fibers. The second layer is coupled to the first layer using a coupling process and includes a plurality of varying densities formed by the second plurality of electrospun polymeric fibers. The first and second layers are configured to degrade via hydrolysis after at least one of a predetermined time or an environmental condition. The three-dimensional electrospun nanofiber scaffold is configured to be applied to the tissue substrate containing the defect.

One aspect of the invention provides a three-dimensional scaffold including at least one layer of highly-aligned fibers. The at least one layer of highly-aligned fibers is curved in a direction substantially perpendicular to a general direction of the fibers. Another aspect of the invention provides a method for fabricating a three-dimensional scaffold. The method includes: electro spinning a plurality of fibers to produce at least one layer of highly-aligned fibers and forming the at least one layer of highly-aligned fibers into a three-dimensional scaffold without disturbing the alignment of the highly-aligned polymer fibers. A further aspect of the invention provides methods for using a three-dimensional scaffold to treat nerve or spinal cord injury.

An apparatus for continuous needless electrospinning of a liquid polymer source into a nanoscale or submicron scale polymer fiber web includes an electrospinning enclosure, a wire drive system located external to the electrospinning enclosure and a plurality of continuous electrode wires. The electrospinning enclosure includes and electrospinning zone and one or more liquid polymer coating devices where liquid polymer is coated onto the plurality of continuous electrode wires. The plurality of continuous electrode wires are parallel to each other, engaged with the wire drive system, and extend through the electrospinning enclosure and the one or more liquid polymer coating devices located therein. High voltage is applied to the plurality of continuous electrode wires in the electrospinning zone to form nanoscale or submicron scale polymer fibers from the liquid polymer coated on the electrode wires.

Ophthalmic suture materials made from biocompatible and biodegradable polymers with high tensile strength for use in drug delivery, methods of making them, and method of using them for ocular surgery and repair have been developed. The suture materials are made from a combination of a biodegradable, biocompatible polymer and a hydrophilic biocompatible polymer. In a preferred embodiment the suture materials are made from a poly(hydroxyl acid) such as poly(1-lactic acid) and a polyalkylene oxide such as poly(ethylene glycol) or a polyalkylene oxide block copolymer. The sutures entrap (e.g., encapsulate) one or more therapeutic, prophylactic or diagnostic agents and provide prolonged release over a period of at least a week, preferably a month.

An apparatus for collecting cross-aligned fiber threads, comprising an elongated assembly having a plurality of segments including at least a first segment, a second segment, and an intermediate segment, the first segment positioned at one end of the intermediate segment and the second segment positioned at an opposite end of the intermediate segment, each segment being electrically chargeable; an electrically chargeable emitter for electrospinning nanoscale fiber streams comprising charged fiber branches, the emitter having a tip positioned offset and between an edge of the first segment and an edge of the second segment; a support structure for rotating the elongated assembly about a longitudinal axis and applying an electrical charge to at least the edges of the first and second segment; at least one electrically chargeable steering electrode for attracting fiber streams, the at least one steering electrode chargeable with an electrical polarity opposing a charge applied to the emitter.

Described are fibrous materials comprising a plurality of fibers having a longitudinal alignment gradient and/or a longitudinal composition gradient. Also described are methods of preparing the fibrous materials thereof and methods of treating organ or tissue damage with the fibrous materials.