Abstract: An apparatus for mixing a particulate material into a liquid includes a pair of variable volume receptacles interlinked by a communication passage. A combined volume of liquid and particulate material is received within the variable volumes, and the volume of the variable volumes is alternately reduced and to force the materials back and forth through the connection passage. The variable volumes may be formed from a rigid walled cylinder having a free floating piston therein, and the piston and inner diameter may have a tight, sealed gap therebetween. To load the piston into the cylinder without effecting the seals, a load apparatus may be used to depress the seals inwardly of the piston and align the piston in the cylinder.

Abstract: Drugs are delivered in a sustained manner from an in vivo depot which is formed from a collagen-based injectable composition. The injectable composition is fluid when injected but undergoes crosslinking in situ to form a crosslinked collagen matrix which encloses the drug to be released. The composition also includes a flexible chain polymer which is similarly charged to the precrosslinked collagen. This flexible chain polymer is enclosed in the matrix as well when the matrix forms and alters the effective porosity of the matrix. The drug diffuses out of the matrix at a rate which depends upon the matrix's effective porosity.

Abstract: The present invention discloses collagen-synthetic polymer matrices which are prepared using a multiple step reaction. The first step of the reaction generally involves reacting collagen with a functionally activated synthetic hydrophilic polymer to form a collagen-synthetic polymer matrix. The synthetic hydrophilic polymer may be mono- or multifunctionally activated, but is preferably difunctionally activated, resulting in the formation of a crosslinked collagen matrix. The second step comprises modifying the collagen-synthetic polymer matrix according to one or more of the following methods: further crosslinking the matrix using a multifunctionally activated synthetic polymer, conjugating the matrix using a monofunctionally activated synthetic polymer, coupling biologically active molecules or glycosaminoglycans to the matrix, crosslinking the matrix using conventional chemical crosslinking agents, or modifying the collagen in the matrix by means of various chemical reactions.

Abstract: Methods for completely or partially blocking, augmenting, sealing, or filling various biological lumens and voids within the body of a patient are disclosed. Lumens include arteries, veins, intestines, Fallopian tubes, and trachea. Voids include various lesions, fissures, diverticulae, cysts, fistulae, aneurysms, or other undesirable voids that may exist within a patient's body. In the most general method of the invention, an effective amount of a biomaterial is administered (e.g., via injection, catheter, or surgical implantation) into the lumen or void. Preferred biomaterial compositions for use in the present invention are disclosed.

Abstract: Collagen-based compositions useful in the attachment of tissues, or the attachment of tissues to synthetic implant materials, are disclosed. The compositions comprise collagen crosslinked using a multifunctionally activated synthetic hydrophilic polymer. A particularly preferred composition comprises fibrillar collagen, a fiber disassembly agent, and a multifunctionally activated synthetic hydrophilic polymer. Methods are disclosed for using the compositions to effect the attachment of a native tissue to the surface of another native tissue, a non-native tissue, or a synthetic implant. Also disclosed are methods of using the compositions to prevent the formation of surgical adhesions.

Abstract: Affinity bound collagen matrices for the delivery of biologically active agents, and methods for preparing such matrices, are disclosed. A preferred method for preparing the matrices of the invention comprises mixing a binding ligand and an active agent together, allowing the resulting binding ligand-active agent mixture to form an affinity bound complex, then combining the resulting affinity bound complex with collagen to form a matrix. Particular affinity bound matrices comprising collagen, heparin, and an active agent are also disclosed, as well as methods for using the matrices of the invention for delivery of biologically active agents.

Abstract: Production of human procollagen or collagen in cells which ordinarily do not produce these molecules is effected by constructing expression systems compatible with mammary glands of non-human mammals. For example, expression systems can be microinjected into fertilized oocytes and reimplanted in foster mothers and carried to term in order to obtain transgenic non-human mammals capable of producing milk containing recombinant human procollagen or collagen. Human procollagen or collagen produced in this manner can be made of a single collagen type uncontaminated by other human or non-human collagens.

Abstract: The present invention discloses a novel method for preparing crosslinked biomaterial compositions for use in the augmentation of soft or hard tissue. In general, the method comprises mixing a biocompatible polymer, which is preferably collagen, with a sterile, dry crosslinking agent, which is preferably a synthetic hydrophilic polymer such as a functionally activated polyethylene glycol. Also provided are preferred processes for preparing sterile, dry crosslinking agents contained within syringes for use in the method of the invention. Methods for sterilization of the crosslinking agent include, but are not limited to, sterile filtration, aseptic processing, and e-beam or gamma irradiation. Methods for providing augmentation of soft or hard tissue using crosslinked biomaterial compositions prepared according to the method of the invention are also disclosed.

Abstract: In accordance with the present invention, stabilized dispersions of collagen fibers that have been treated in order to inactivate infectious agents and methods of stabilizing such collagen fibers are provided.

Abstract: Collagen-based compositions useful in the attachment of tissues, or the attachment of tissues to synthetic implant materials, are disclosed. The compositions comprise collagen crosslinked using a multifunctionally activated synthetic hydrophilic polymer. A particularly preferred composition comprises fibrillar collagen, a fiber disassembly agent, and a multifunctionally activated synthetic hydrophilic polymer. Methods are disclosed for using the compositions to effect the attachment of a native tissue to the surface of another native tissue, a non-native tissue, or a synthetic implant.

Abstract: Anti-adhesion films useful for the prevention of surgical adhesions are disclosed. These films comprise substrate materials (such as collagen) and hetero-bifunctional anti-adhesion binding agents, wherein the substrate material is covalently linked to receptive tissue within the body of a patient via the binding agent. Preferred binding agents comprise substrate-reactive and tissue-selective functional groups. Anti-adhesion compositions useful for the formation of such films are also disclosed.

Abstract: Various forms of chemically modified collagen are covalently crosslinked with activated synthetic hydrophilic polymers to form optically clear biocompatible conjugates useful in a variety of medical applications, particularly in ophthalmic devices. The chemically modified collagen is in substantially nonfibrillar form at pH 7 and is preferably succinylated or methylated collagen. The synthetic hydrophilic polymer is preferably an activated polymeric glycol, most preferably, a di- or multifunctionally activated polyethylene glycol. Materials and devices formed with the chemically modified collagen-synthetic polymer conjugates have good optical clarity, mechanical strength, and moldability.

Abstract: Pharmaceutically acceptable, non-immunogenic compositions are formed by covalently binding atelopeptide collagen to pharmaceutically pure, synthetic, hydrophilic polymers via specific types of chemical bonds to provide collagen/polymer conjugates. The atelopeptide collagen can be type I, type II or type III and may be fibrillar or non-fibrillar. The synthetic hydrophilic polymer may be polyethylene glycol and derivatives thereof having a weight average molecular weight over a range of from about 100 to about 20,000. The compositions may include other components such as liquid, pharmaceutically acceptable, carriers to form injectable formulations, and/or biologically active proteins such as growth factors. The collagen-polymer conjugates of the invention generally contain large amounts of water when formed. The conjugates can be dehydrated to form a relatively solid object.

Abstract: The present invention discloses a novel method for preparing crosslinked biomaterial compositions for use in the augmentation of soft or hard tissue. In general, the method comprises mixing a biocompatible polymer, which is preferably collagen, with a sterile, dry crosslinking agent, which is preferably a synthetic hydrophilic polymer such as a functionally activated polyethylene glycol. Also provided are preferred processes for preparing sterile, dry crosslinking agents contained within syringes for use in the method of the invention. Methods for sterilization of the crosslinking agent include, but are not limited to, sterile filtration, aseptic processing, and e-beam or gamma irradiation. Methods for providing augmentation of soft or hard tissue using crosslinked biomaterial compositions prepared according to the method of the invention are also disclosed.

Abstract: Collagen, particularly atelopeptide collagen, exhibits improved handling characteristics when chemically conjugated and/or crosslinked with a synthetic hydrophilic polymer.

Abstract: The invention pertains to a delivery device for controlling the injection of discrete quantities of fluid injectable materials through a conduit such as a hypodermic needle or a catheter. The delivery device is coupled to a pressurized driving fluid source, and the control means provides controlled passage of pressurized driving fluid into a syringe body to act against a piston which forces the fluid injectable material out the needle or catheter.In addition to the delivery device, the invention includes a needle depth guide which is preferably used in combination with the delivery device for cosmetic applications when a hypodermic needle is used to deliver a fluid injectable material to the dermis.

Abstract: The present invention discloses a novel method for preparing crosslinked biomaterial compositions for use in the augmentation of soft or hard tissue. In general, the method comprises mixing a biocompatible polymer, which is preferably collagen, with a sterile, dry crosslinking agent, which is preferably a synthetic hydrophilic polymer such as a functionally activated polyethylene glycol. Also provided are preferred processes for preparing sterile, dry crosslinking agents contained within syringes for use in the method of the invention. Methods for sterilization of the crosslinking agent include, but are not limited to, sterile filtration, aseptic processing, and e-beam or gamma irradiation. Methods for providing augmentation of soft or hard tissue using crosslinked biomaterial compositions prepared according to the method of the invention am also disclosed.

Abstract: Collagen, particularly atelopeptide collagen, exhibits improved handling characteristics when chemically conjugated and/or crosslinked with a synthetic hydrophilic polymer.

Abstract: Pharmaceutically acceptable, nonimmunogenic compositions are formed by covalently binding glycosaminoglycans or derivatives thereof, to hydrophilic synthetic polymers via specific types of chemical bonds to provide biocompatible conjugates. Useful glycosaminoglycans include hyaluronic acid, the chondroitin sulfates, keratan sulfate, chitin and heparin, each of which is chemically derivatized to react with a hydrophilic synthetic polymer. The conjugate comprising a glycosaminoglycan covalently bound to a hydrophilic synthetic polymer may be further bound to collagen to form a three component conjugate having different properties. The hydrophilic synthetic polymer may be polyethylene glycol and derivatives thereof having an average molecular weight over a range of from about 100 to about 100,000. The compositions may include other components such as fluid, pharmaceutically acceptable carriers to form injectable formulations, and/or biologically active proteins such as growth factors or cytokines.

Abstract: Pharmaceutically acceptable, nonimmunogenic compositions are formed by covalently binding glycosaminoglycans or derivatives thereof, to hydrophilic synthetic polymers via specific types of chemical bonds to provide biocompatible conjugates. Useful glycosaminoglycans include hyaluronic acid, the chondroitin sulfates, keratan sulfate, chitin and heparin, each of which is chemically derivatized to react with a hydrophilic synthetic polymer. The conjugate comprising a glycosaminoglycan covalently bound to a hydrophilic synthetic polymer may be further bound to collagen to form a three component conjugate having different properties. The hydrophilic synthetic polymer may be polyethylene glycol and derivatives thereof having an average molecular weight over a range of from about 100 to about 100,000. The compositions may include other components such as fluid, pharmaceutically acceptable carriers to form injectable formulations, and/or biologically active proteins such as growth factors or cytokines.