Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
129 words
A method for preparing a biocompatible biodegradable polyhydroxyalkanoate composition that has a controlled degradation rate under physiological conditions, wherein the mass loss, as measured bvxas chromatography, is greater than 5% over a six week period in vivo, or wherein the average molecular mass loss, as measured by gel permeation chromatography, decreases 20% to 50% over a ten week period in vivo, comprising (a) incorporating monomeric units as chemical linkages into the polymer backbone which alter the chemical stability of the polymer backbone; (b) replacing linkages in said polymer backbone which alter the chemical stability of the polymer backbone; (c) incorporating pendant groups into the polymer which alter the chemical stability of the polymer backbone; (d) incorporating additives which alter the chemical stability of the polymer; or (e) combinations thereof.
Claim 2
Independent Claim
129 words
A method for preparing a biocompatible biodegradable polyhydroxyalkanoate composition that has a controlled degradation rate under physiological conditions, wherein the mass loss, as measured bvxas chromatography, is greater than 5% over a six week period in vivo, or wherein the average molecular mass loss, as measured by gel permeation chromatography, decreases 20% to 50% over a ten week period in vivo, comprising (a) incorporating monomeric units as chemical linkages into the polymer backbone which alter the chemical stability of the polymer backbone; (b) replacing linkages in said polymer backbone which alter the chemical stability of the polymer backbone; (c) incorporating pendant groups into the polymer which alter the chemical stability of the polymer backbone; (d) incorporating additives which alter the chemical stability of the polymer; or (e) combinations thereof.
Claim 3
Dependent Claim
32 words
The method of claim 1 further comprising forming the polyhydroxyalkanoate composition using a method selected from the group consisting of fermentation, enzymatic synthesis, chemical synthesis, melt processing, reactive blending, and recombinant techniques.
Claim 4
Dependent Claim
15 words
The method of claim 2 wherein the composition is derived by fermentation using a co-feed.
Claim 5
Dependent Claim
12 words
The method of claim 2 wherein the fermentation process uses transgenic bacteria.
Claim 6
Dependent Claim
20 words
The method of claim 2 wherein the chemical synthesis is selected from the group consisting of insertion, transesterification and metathesis.
Claim 7
Dependent Claim
15 words
The method of claim 1 wherein the presence of the additional unit(s) promotes chain scission.
Claim 8
Dependent Claim
14 words
The method of claim 1 wherein the units contain more than two functional groups.
Claim 9
Dependent Claim
16 words
The method of claim 1 wherein a heteroatom grouping is incorporated into the polymer backbone chain.
Claim 10
Dependent Claim
20 words
The method of claim 8 wherein the heteroatom grouping is selected from the group consisting of oxygen, sulfur and nitrogen.
Claim 11
Dependent Claim
30 words
The method of claim 1 wherein the units are incorporated into the polymer backbone with chemical linkages selected from the group consisting of ester, amide, ether, carbamate, anhydride, and carbonate.
Claim 12
Dependent Claim
26 words
The method of claim 1 wherein the units are selected from the group consisting of 2-hydroxyacids; 2-hydroxyalkoxyacetic acids; amino acids; amino alcohols; diacids; triols; and tetraols.
Claim 13
Dependent Claim
11 words
The method of claim 11 wherein the 2-hydroxyacids are 2-hydroxyalkanoic acids.
Claim 14
Dependent Claim
12 words
The method of claim 12 wherein the 2-hydroxyalkanoic acid is lactic acid.
Claim 15
Dependent Claim
12 words
The method of claim 12 wherein the 2-hydroxyalkanoic acid is glycolic acid.
Claim 16
Dependent Claim
11 words
The method of claim 11 wherein the 2-hydroxyacids are 2-hydroxyalkenoic acids.
Claim 17
Dependent Claim
23 words
The method of claim 11 wherein the 2-hydroxyalkoxyacetic acids are selected from the group consisting of 2-hydroxyethoxy acetic acid and 3-hydroxypropoxy acetic acid.
Claim 18
Dependent Claim
16 words
The method of claim 1 comprising pendant groups that catalyze the degradation of the polymer backbone.
Claim 19
Dependent Claim
16 words
The method of claim 17 wherein the pendant groups are selected from acidic and basic groups.
Claim 20
Dependent Claim
14 words
The method of claim 17 comprising reactant pendant groups that cause polymer chain scission.
Claim 21
Dependent Claim
16 words
The method of claim 19 wherein the reactant pendant groups are selected from nucleophiles and electrophiles.
Claim 22
Dependent Claim
21 words
The method of claim 17 wherein the pendant groups are selected from the group consisting of alcohols, acids and amine groups.
Claim 23
Dependent Claim
11 words
The method of claim 1 wherein the additives promote chain scission.
Claim 24
Dependent Claim
32 words
The method of claim 22 wherein the additives are selected from the group consisting of acids, bases, electrophiles, nucleophiles, plasticizers, polymers, pore forming agents, and agents designed to reduce the polymer crystallinity.
Claim 25
Dependent Claim
9 words
The method of claim 23 comprising pore forming agents.
Claim 26
Dependent Claim
13 words
The method of claim 24 wherein the pore forming agents are lyophilizable particles.
Claim 27
Dependent Claim
12 words
The method of claim 24 wherein the pore forming agents absorb water.