Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – From reactant having at least one -n=c=x group as well as...
Patent
1998-12-15
2000-03-21
Sergent, Rabon
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
From reactant having at least one -n=c=x group as well as...
424 7817, 424 7827, 424 7837, 524 27, 525 542, 528 72, C08G 1832, C08G 1838, A61K 31765, A61K 31785, A61K 3180
Patent
active
060404159
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to biocompatible polyurethanes or polyurethane ureas, in particular polyurethanes or polyurethane ureas which show good antithrombogenicity when employed as medical materials to be brought into direct contact with the living body or constituents of the living body.
BACKGROUND ART
In recent years, high-molecular materials excellent in processability, elasticity and flexibility have been widely used as medical materials. It is expected that such materials will find wider use in artificial organs such as artificial kidneys, artificial lungs, extracorporeal circulation devices and artificial blood vessels, as well as disposable products such as syringes, blood bags and cardiac catheters. Materials of these products for medical use are required to have, in addition to sufficient mechanical strength and durability, biological safety which particularly means a property of not causing coagulation of blood upon contact therewith, i.e., antithrombogenicity.
Conventional methods for imparting antithrombogenicity to medical materials are generally classified into the following three groups: fibrinolytic activator (e.g., urokinase) on the surface of the material; charge or hydrophilicity; and method") is further subdivided into (A) blending of a polymer with heparin, (B) coating of the material surface with an organic solvent-soluble heparin, (C) ionic bonding of heparin to a cationic group in the material, and (D) covalent bonding of the material and heparin.
In the method (1), heparin or urokinase introduced to the material surface exhibits antithrombogenicity or lytic activity on thrombus at the early stage of introduction of the material. In a long-term use, however, the antithrombogenic agents tend to dissolve out, lowering the ability of the material. In other words, according to the methods (A), (B) and (C), a long-term use under physiological conditions generally results in easy release of heparin or the like, making it difficult to achieve sufficient performance of medical materials which are used as implanted in the living body for a long period. The method (D) is beneficial in that the covalently bonded heparin is unlikely to be released, but conventional bonding techniques often alter the conformation of D-glucose or D-gluconic acid constituting heparin, whereby the anticoagulant effect reduces.
The methods (C) and (D) require selection of materials containing a functional group usable for immobilization of heparin, or introduction of such a functional group into the material. Accordingly, these methods narrow the range of usable materials or deteriorate the mechanical strength of the material due to the introduction of the functional group. Moreover, the complicated manipulation may increase the steps necessary for preparing the material.
In the methods (2) and (3), antithrombogenicity can be imparted to the material by introducing a biocompatible functional group. As described above, when an anticoagulating mucopolysaccharide (e.g., heparin) or a fibrinolytic activator (e.g., urokinase) is immobilized on the material, the antithrombogenicity of the material reduces as the antithrombogenic agents dissolve out. It is therefore difficult to retain the antithrombogenicity for a long period. In contrast, a material into which a biocompatible functional group has been introduced can retain the antithrombogenicity during long-term contact with the living body.
Biocompatible functional groups recently actively researched include phosphorylcholine structures. Phosphorylcholine structures are analogous to the structure of a phospholipid forming biomembranes, i.e., phosphatidylcholine. Accordingly, high-molecular materials containing phosphorylcholine structures in the molecule have high affinity to the living body and are useful as antithrombogenic materials.
For example, polymers containing 2-methacryloyloxyethylphosphorylcholine is analogous in structure to phosphatidylcholine, one of the constituents of external walls of cells. When a phospholipid derived from th
REFERENCES:
patent: 5422402 (1995-06-01), Bowers et al.
patent: 5453467 (1995-09-01), Bamford et al.
patent: 5591882 (1997-01-01), Straford et al.
patent: 5599587 (1997-02-01), Bowers et al.
patent: 5658561 (1997-08-01), Nakabayashi et al.
patent: 5712326 (1998-01-01), Jones et al.
Yamada, M., et al., "Synthesis and Properties of Polyurethanes Containing Phosphatidylcholine Analogues in the Side Chains," Pure Appl. Chem., vol. A32, No. 7, pp. 1235-1242 (1995).
Yamada, M., et al., "Synthesis and Properties of Polymers Containing Phosphatidylcholine Analogues in the Main Chains and Long Alkyl Groups in the Side Chains," Pure Appl. Chem., vol. A32, No. 10, pp. 1723-1733 (1995).
Li, Y., et al., "Novel Blood Compatible Polyurethanes Containing Long-chain Alkyl Groups and Phosphatidylcholine Analogues," Macromol. Chem. Phys., vol. 196, pp. 3143-3153 (1995).
Yamada, M., et al., "Synthesis and Properties of Polyurethanes Containing Phosphatidylcholine Analogues in the Polymer Backbone" Macromol. Rapid Commun., vol. 16, pp. 25-30 (1995).
Li, Y., et al., "Synthesis and Characterization of Polyurethanes Containing Cholesterol and Phosphatidylcholine Analogous Moieties," Macromol. Rapid Commun., vol. 16, pp. 253-258 (1995).
Li, Y., et al., "A new Haemocompatible Phospholipid Polyurethane Based on Hydrogenated Poly-(isoprene) Soft Segment," J. Biomater. Sci. Polymer Edn., vol. 7, No. 10, pp. 893-904 (1996).
Chen, T., et al., "Synthesis and Properties of New Segmented Block Poly(urethane-urea)s Containing Phosphatidylcholine Analogues and Polybutadienes," Macromol. Chem. Phys., vol. 197, pp. 1587-1597 (1996).
Li, Y., et al., "The Effect of Alkyl Chain Length of Amphiphilic Phospholipid Polyurethanes on Haemocompatibilities," Macromol. Chem. Phys., vol. 197, pp. 2827-2835 (1996).
Li, Y., et al., "Synthesis of Comb-Like Polyurethanes Containing Hydrophilic Phosphatidylcholine Analogues in the Main Chains and Hydrophobic Long Chain Alkyl Groups in the Side Chains," Marcromol. Rapid Commun., vol. 17, pp. 737-744 (1995).
Ishihara, K., et al., "Preparation of Phospholipid Polymers and Their Properties as Polymer Hydrogel Membranes," Polymer Journal, vol. 22, No. 5, pp. 355-360 (1990).
Ueda, T., et al., "Preparation of 2-Methacryloyloxyethyl Phosphorylcholine Copolymers with Alkyl Methacrylates and Their Blood Compatibility," Polymer Journal, vol. 24, No. 11, pp. 1259-1269 (1992).
Arimori Susumu
Monden Noriko
Seko Masahiro
Tanaka Masakazu
Yokota Hideyuki
Sergent Rabon
Toyobo Co. Ltd.
LandOfFree
Biocompatible polymers does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Biocompatible polymers, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Biocompatible polymers will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-731302