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US4741872A
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Preparation of biodegradable microspheres useful as carriers for macromolecules
Assignee: University of Kentucky Research Foundation
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Filing: 1986-05-16
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Granted: 1988-05-03
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Expires: 2006-05-16
Abstract
Abstract A method for preparing biodegradable microspheres having a three-dimensional network in which biologically active macromolecular agents are physically entrapped therein. The microsphere is able to degrade and release the macromolecular agent at a controlled rate. The method involves emulsifying a vinyl derivative of a biodegradable hydrophilic polymer, a water-soluble monovinyl monomer and a biologically active macromolecule in water, and copolymerizing the biodegradable hydrophilic polymer and the water-soluble monovinyl monomer such that the biologically active macromolecule is entrapped therein.
Inventors
- 👤 Patrick P. De Luca
- 👤 Frantisek Rypacek
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:50
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/14; A61K9/16; A61K9/1682; A61K9/1694; A61K9/1605; A61K9/1629; A61K9/1641; A61K9/1652; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2984; Y10T428/2985; Y10T428/2987
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
74 words
A method for preparing biodegradable microspheres having a three-dimensional network in which biologically active macromolecular agents are physically entraoped therein, said microsphere being able to release the macromolecular agent at a controlled rate, comprising emulsifying a vinyl derivative of a biodegradable hydrophilic polymer, a water-soluble monovinyl monomer and a biologically active macromolecule in water, and copolymerizing the biodegradable hydrophilic polymer and the water-soluble monovinyl monomer such that the biologically active macromolecule is entrapped therein.
Claim 2
Independent Claim
74 words
A method for preparing biodegradable microspheres having a three-dimensional network in which biologically active macromolecular agents are physically entraoped therein, said microsphere being able to release the macromolecular agent at a controlled rate, comprising emulsifying a vinyl derivative of a biodegradable hydrophilic polymer, a water-soluble monovinyl monomer and a biologically active macromolecule in water, and copolymerizing the biodegradable hydrophilic polymer and the water-soluble monovinyl monomer such that the biologically active macromolecule is entrapped therein.
Claim 3
Dependent Claim
40 words
The method according to claim 1, wherein the biodegradable hydrophilic polymer is prepared by the copolymerization of a vinyl derivative of a biodegradable hydrophilic polymer which contains at least two vinyl groups or substituted vinyl groups per average polymer chain.
Claim 4
Dependent Claim
70 words
The method according to claim 2, wherein the vinyl derivative of the biodegradable hydrophilic polymer has the formula: CH.sub.2 ═CR.sub.1 --(CH.sub.2).sub.n -X (I) wherein R 1 is a hydrogen atom or a methyl group; n is 0, 1 or 2; X is a radical having the formula: ##STR2## and R 2 represents the biodegradable hydrophilic polymer which contains at least two vinyl or substituted vinyl groups per average polymer chain.
Claim 5
Dependent Claim
34 words
The method according to claim 3, wherein the biodegradable hydrophilic polymer is selected from the group consisting of polysaccharides, proteinaceous polymers, soluble derivatives of polysaccharides, soluble derivatives of proteinaceous polymers, polypeptides, polyesters, and polyorthoesters.
Claim 6
Dependent Claim
14 words
The method according to claim 4, wherein the biodegradable hydrophilic polymer is a polysaccharide.
Claim 7
Dependent Claim
13 words
The method according to claim 5, wherein the polysaccharide is a starch derivative.
Claim 8
Dependent Claim
14 words
The method according to claim 4, wherein the biodegradable hydrophilic polymer is a polypeptide.
Claim 9
Dependent Claim
13 words
The method according to claim 7, wherein the polypeptide is poly-(N-hydroxyalkyl)asparagine or poly-(N-hydroxyalkyl)glutamine.
Claim 10
Dependent Claim
35 words
The method according to claim 1, wherein the water-soluble monovinyl monomer is selected from the group consisting of hydrophilic esters and/or amides of acrylic or methacrylic acids, water-soluble vinyl derivatives, acrylic acid and methacrylic acid.
Claim 11
Dependent Claim
33 words
The method according to claim 1, wherein the ratio between the biodegradable hydrophilic polymer to the water-soluble monovinyl monomer is in the range of about 1:5 to about 40:1 on a weight basis.
Claim 12
Dependent Claim
22 words
The method according to claim 1, wherein the biologically active macromolecular agent is a hormone, protein, peptide, vaccine, enzyme or enzyme inhibitor.
Claim 13
Dependent Claim
22 words
The method according to claim 1, wherein the polymerization is conducted at a temperature of about 0° C. to about 50° C.
Claim 14
Dependent Claim
16 words
The method according to claim 1, wherein the polymerization is conducted using the bead polymerization technique.
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