摘要:
Microspheres for controlled release of a bioactive agent are disclosed, and in particular, blend, cross-linkable poly(propylene fumarate) for immobilization and controlled drug delivery. The microsphere includes poly(propylene fumarate), a polymeric material other than poly(propylene fumarate) (e.g., poly(lactic-co-glycolic acid)), and a bioactive agent. The bioactive agent is selected depending on the physiological effect desired. For example, in bone regeneration applications, the bioactive agent may be selected from osteoinductive agents, peptides, growth hormones, osteoconductive agents, cytokines and mixtures thereof. The bioactive agent is dispersed in the microsphere, the microsphere has a diameter in the range of 1 to 300 micrometers, the poly(propylene fumarate) and poly(lactic-co-glycolic acid) are distributed in the microsphere, and the microsphere releases the bioactive agent in a sustained manner after an initial burst release. The microspheres may be covalently attached to a poly(propylene fumarate) scaffold for tissue regeneration applications in which the bioactive agent is released from the scaffold.
摘要:
Hydrogel microparticles with entrapped liquid are used as the porogen to reproducibly form interconnected pore networks in a porous scaffold. In one embodiment, a biodegradable unsaturated polymer, a crosslinking agent, and a porogen comprising biodegradable hydrogel microparticles are mixed together and allowed to form a porous scaffold in an mold or in a body cavity. Example biodegradable unsaturated polymers include poly(propylene fumarate) and poly(e-caprolactone-fumarate). The cosslinking agent may be a free radical initiator, or may include a free radical initiator and a monomer capable of addition polymerization. Example hydrogel microparticles include uncrosslinked or crosslinked collagen , an uncrosslinked or crosslinked collagen derivative, and an uncrosslinked or crosslinked synthetic biodegradable polymer such as oligo(poly(ethylene glycol) fumarate).
摘要:
A composition is disclosed which comprises (i) a macromer prepared by reacting an unsaturated diacid having a carbon-carbon double bond and a saturated diacid, and (ii) a bioactive ceramic grafted to the macromer. In one embodiment, the unsaturated diacid having a carbon-carbon double bond is fumaric acid, the saturated diacid is compatible with fumaric acid and poly(propylene fumarate) such as succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid and mixtures thereof, and the bioactive ceramic is hydroxyapatite. In another embodiment, hydroxyapatite is grafted with a biodegradable and crosslinkable macromer comprising silane units alternating with furnarate and adipate units.
摘要:
A composition is disclosed which comprises (i) a macromer prepared by reacting an unsaturated diacid having a carbon-carbon double bond and a saturated diacid, and (ii) a bioactive ceramic grafted to the macromer. In one embodiment, the unsaturated diacid having a carbon-carbon double bond is fumaric acid, the saturated diacid is compatible with fumaric acid and poly(propylene fumarate) such as succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid and mixtures thereof, and the bioactive ceramic is hydroxyapatite. In another embodiment, hydroxyapatite is grafted with a biodegradable and crosslinkable macromer comprising silane units alternating with furnarate and adipate units.
摘要:
Fumaric acid or a salt thereof, such as a fumaryl halide (e.g., fumaryl chloride), which contains unsaturated carbon-carbon double bonds that can be used for in situ crosslinking, is copolymerized with a biodegradable poly(caprolactone) macromer that has a flexible backbone such that the resulting copolymer may self-crosslink in the absence of a crosslinking agent. The bio-compatible and bioresorbable poly(caprolactone fumarate) biomaterial is useful in the fabrication of injectable and in-situ hardening scaffolds for application in skeletal reconstruction.
摘要:
Bioresorbable compositions for treating skeletal tissue are disclosed. The biomedical compositions are formed from a polylactide polymer, a polyglycolide polymer, or a poly(lactic-co-glycolic acid) polymer having a relatively low molecular weight. For instance, the average number molecular weight of the polymer is generally less than 10,000, such as from about 500 to about 5,000. Fumarate groups are incorporated into the low molecular weight polymer that provide crosslinking sites. If desired, ethylene oxide groups and ceramic particles may also be incorporated into the polymer for producing compositions having a variety of properties. For example, the biomedical composition of the present disclosure can be used to treat soft skeletal tissue or to treat hard skeletal tissue. The biomedical compositions are biodegradable and can contain various therapeutic, beneficial and pharmaceutical agents that may be released during degradation of the polymer.
摘要:
In accordance with certain embodiments of the present disclosure, a method for forming a laminated nanocomposite is provided. The method includes applying a hydrogel precursor solution to a first layer of poly(L-lactide) nanofiber mesh. A second layer of poly(L-lactide) nanofiber mesh is stacked on the first layer with at least a portion of the hydrogel precursor solution being situated between the first layer and the second layer. The method further includes compressing the first layer and second layer together wherein the first layer and second layer are crosslinked to one another by the hydrogel precursor solution to form a laminated nanocomposite. Furthermore, the laminate layers, prior to crosslinking, can be wrapped around a rod and crosslinked to form a laminated tubular nanocomposite.
摘要:
In accordance with certain embodiments of the present disclosure, a self-assembling biodegradable nanoparticle is provided. The nanoparticle includes a degradable synthetic polymer chain, a sequence of non-polar amino acids, and a sequence of ionic amino acids. The nanoparticle has a diameter of from about 50 nm to about 150 nm.
摘要:
Bioresorbable compositions for treating skeletal tissue are disclosed. The biomedical compositions are formed from a polylactide polymer, a polyglycolide polymer, or a poly(lactic-co-glycolic acid) polymer having a relatively low molecular weight. For instance, the average number molecular weight of the polymer is generally less than 10,000, such as from about 500 to about 5,000. Fumarate groups are incorporated into the low molecular weight polymer that provide crosslinking sites. If desired, ethyl-lene oxide groups and ceramic particles may also be incorporated into the polymer for producing compositions having a variety of properties. For example, the biomedical composition of the present disclosure can be used to treat soft skeletal tissue or to treat hard skeletal tissue. The biomedical compositions are biodegradable and can contain various therapeutic, beneficial and pharmaceutical agents that may be released during degradation of the polymer.
摘要:
A method for fabrication of a scaffold by fused deposition modeling is provided. The method includes forming a sacrificial mold with fused deposition modeling, the sacrificial mold comprising a dissolvable material. The method further includes infusing the sacrificial mold with a biodegradable composition and applying a solvent to the biodegradable composition infused sacrificial mold to dissolve the sacrificial mold and leave a scaffold formed from the biodegradable composition.