Abstract: The present invention relates to a balloon expandable stent mounted on a balloon catheter, the entire assembly being overcoated with a coherent polymer coating, which is preferably substantially continuous over the circumference and, more preferably, axial length of the stem on the balloon. The polymer coating improves retention of the stent on the balloon during delivery and does not adversely effect the deployment characteristics, nor the balloon failure characteristics. The product is made by mounting the stent on the balloon and coating the assembly with a liquid coating composition containing a suitable polymer followed by curing of the coating. The polymer is biocompatible and preferably crosslinkable in the coating composition, and crosslinked in the final product. A suitable polymer is formed from monomers including a zwitterionic, preferably a phosphoryl choline, group, and monomers including a trialkoxysilyl group.

Abstract: The present invention relate to a balloon expandable stent mounted on a balloon catheter, the entire assembly being overcoated with a coherent polymer coating, which is preferably substantially continuous over the circumference and, more preferably, axial length of the stent on the balloon. The polymer coating improves retention of the stent on the balloon during delivery and does not adversely effect the deployment characteristics, nor the balloon failure characteristics. The product is made by mounting the stent on the balloon and coating the assembly with a liquid coating composition containing a suitable polymer followed by curing of the coating. The polymer is biocompatible and preferably crosslinkable in the coating composition, and crosslinked in the final product. A suitable polymer is formed from monomers including a zwitterionic, preferably a phosphoryl choline, group, and monomers including a trialkoxysilyl group.

Abstract: A biocompatibilising process in which a substrate having a surface which bears substrate pendant functional groups is biocompatibilised by coating it with a coating composition containing a polymer formed from a radical polymerisable monomers including a radical polymerisable zwitterionic monomer and a radical polymerisable monomer containing a reactive group to form a polymer having zwitterionic groups and pendant reactive groups and the said pendant reactive groups are reacted to form covalent bonds with said substrate pendant functional group and thereby form a stable coating of polymer on the said surface.

Abstract: A biocompatibilising process in which a substrate having a surface which bears substrate pendant functional groups is biocompatibilised by coating it with a coating composition containing a polymer formed from a radical polymerisable monomers including a radical polymerisable zwitterionic monomer and a radical polymerisable monomer containing a reactive group to form a polymer having zwitterionic groups and pendant reactive groups and the said pendant reactive groups are reacted to form covalent bonds with said substrate pendant functional group and thereby form a stable coating of polymer on the said surface.

Abstract: A polyion complex (PIC) is formed of an anionic soluble polymer formed from ethylenically unsaturated monomers including at least one anionic or monomer and a cationic soluble polymer formed from ethylenically unsaturated monomer including at least one cationic monomer, in which the monomers used to form at lest one of the polymers comprise a switterionic monomer and in which the monomers used to form at least one of the polymers include non-ionic monomer, preferably C1-24 alkyl(meth)acrylate, in which the overall ratio of anionic groups to cationic groups in the PIC is in the range 1.5:1 to 1:1.5, and in which the polymers are combined in ratios to provide a PIC in which there are units derived from zwitterionic monomer in an amount in the range 1 to 70 mole % based on total monomer derived units in the PIC and there are units derived from non-ionic monomer in an amount in the range 0 to 60 mole % based on total monomer derived units in the PIC.

Abstract: A catheter and stent combination for insertion into the lumen of a human or animal body. The catheter has an elongate body with proximal and distal ends, the body comprising a hollow tubular member. At least one section of the walls of the tubular member in the distal region is corrugated and the stent is positioned thereover.

Abstract: An insoluble polymer is deposited in a body cavity for instance to embolize a vein or pack an aneurysm, the polymer having pendant zwitterionic groups to improve biocompatibility. The insoluble polymer is preferably formed by an in situ gelling step in which a charged, preferably soluble, polymer having pendant zwitterionic groups is introduced in the form of a composition in which it is soluble and is gelled by being mixed with a counterionically charged soluble polymer (polyelectrolyte), to form a polyion complex. Preferably the or each soluble polymer is formed by polymerizing ethylenically unsatured monomers including a zwitterionic monomer, for instance 2-methacryloyloxyethyl-2′-trimethylammoniumethyl phosphate inner salt, an ionic monomer such as trimethylammonium alkyl(alk)acrylate or a sulphoalkyl(alk)acrylate and optionally a diluent monomer such as an alkyl(alk)acrylate.

Abstract: A process for coating a blood-contacting surface comprising applying a solution of a fatty acid diester of phosphatidyl choline in an organic solvent to the surface and removing the solvent, provides a non-thrombogenic coating of phosphatidyl choline di-ester to the surface. Material for use in a blood-contacting device having such a coating and a blood-contacting device having such a coating.

Abstract: An apparatus for coating tubular members, such as stents comprises a liquid reservoir and a stent support member for supporting, in use, a tubular member. Support member dipping means places the support member in the liquid reservoir in use and draws the support member therefrom. Pressure differential generating means generates a pressure differential. The stent support member is arranged to provide a central passageway through a stent placed thereon, the central passageway having a plurality of perforations formed therein, and the pressure differential generating means is arranged to generate, in use, a pressure differential between the passageway and the tubular member.

Abstract: Cross-linked copolymers which are obtained by polymerising a neutral diluent monomer or monomers, a monomer or monomers bearing a center of permanent positive charge, and a bifunctional and/or trifunctional cross-linking agent, are suitable for use in contact lenses. Process for producing them by copolymerisation, contact lens material comprising them, contact lenses made of them and processes for producing contact lenses from them.

Abstract: Emulsion polymerisations are described in which the monomers include an ethylenically unsaturated ammonium phosphate ester monomer. The processes may be conducted with high total solids, to produce a polymer latex having a solids content in the range 20 to 60%, for instance in the range 25 to 50% by weight. Preferably comonomers include lower alkyl and higher alkyl methacrylate selected to give desirable glass transition temperatures and coalescing films, zwitterionic comonomers, polyethoxylated comonomers to confer desired biocompatibility and latex stability as well as good wetting for a film formed of the polymer and may contain crosslinking monomers, reactive monomers, anionic monomers and/or cationic monomers. The latexes are stable, even when the process is carried out in the substantial absence of non-polymerisable emmulsifier. Coatings formed from the latexes containing zwitterionic comonomer have good biocompatibilising properties.

Abstract: A balloon catheter comprising a fluid dispensing device. The device comprises a housing defining a chamber for retaining, in use, balloon inflation fluid. An outlet attaches, in use, to a catheter inflation lumen, and dispensing means dispenses fluid, in use, from the chamber via the outlet into the catheter lumen. An indicator indicates when a predetermined volume of fluid has been dispensed from the outlet.

Abstract: Anion exchange material surfaces are provided with zwitterionic and cationic groups, preferably by coating with a polymer formed from monomers including a zwitterionic monomer, a cationic monomer and, optionally, a termonomer providing stable binding at the substrate surface. The ion exchange materials may be used to scavenge heparin from blood by an ion exchange separation process. The zwitterionic group reduces the rate of fouling by biological materials such as proteins.

Abstract: Cross-linked copolymers which are obtainable by polymerising a neutral diluent monomer or monomers, a monomer or monomers bearing a center of permanent positive charge, and a bifunctional and/or trifunctional cross-linking agent, are suitable for use in contact lenses. Process for producing them by copolymerization, contact lens material comprising them, contact lenses made of them and processes for producing contact lenses from them.

Abstract: Cross-linked copolymers which are obtainable by polymerizing a neutral diluent monomer or monomers, a monomer or monomers bearing a center of permanent positive charge, and a bifunctional and/or trifunctional cross-linking agent, are suitable for use in contact lenses. Process for producing them by copolymerization, contact lens material comprising them, contact lenses made of them and processes for producing contact lenses from them.

Abstract: The biocompatibility of various polymers are improved by blending with them a polymer including a zwitterionic group. The zwitterionic group is usually an ammonium phosphate ester zwitterionic group and the polymer containing it may be produced by the free radical polymerisation of ethylenically unsaturated monomers including a monomer bearing the zwitterionic group. Blending of the two polymers may be achieved by dry blending particulate polymers or by mixing the polymers in liquid dispersion or solution followed by removal of the liquid medium. The fibrinogen absorption and/or platelet activation of polymers may be reduced to a value of less than 80% or even less than 60% of the base polymer by introducing amounts of more than 10% or more than 30% of the zwitterionic group containing polymer. Preferred blends are of copolymers of 2-(methacryloyloxyethyl)-2′-(trimethylammonium)ethyl phosphate inner salt with higher alkyl(meth)acrylate, blended with olefin polymers and/or with rubber latices.

Abstract: A tip for attachment, in use, to the distal end of a catheter for insertion into a body lumen. The tip comprises an attachment region. The attachment region is formed from a material selected to have at least one characteristic having a first parameter of a predetermined value to enable attachment at the tip in use.

Abstract: A polymer is formed from monomers including a zwitterionic monomer, a cationic monomer and a hydrophobic termonomer. The polymer may be cross-linkable. The polymer may be coated onto a surface from a liquid coating composition followed by contacting the coated surface with heparin. The double coated substrates have improved heparin activity over extended periods as compared to heparinised surfaces which are commercially available. Other anionically charged mucopolysaccharides may be used. The polymers may also scavenge heparin from treated blood to avoid use of potentially toxic heparin inhibitors. Preferably the terpolymer is formed from 2-methacryloyloxyethyl-2-(trimethylamonium)phosphate inner salt, choline methacrylate and n-dodecyl methacrylate.

Abstract: A biocompatibilizing process in which the surface of a material in need of being biocompatibilized is coated with a copolymer formed by radical polymerization of ethylenically unsaturated monomers comprising a zwitterionic monomer having a sulphobetaine group and a comonomer having a group selected for providing a stable coating of polymer on the said surface. The comonomer may have a hydrophobic group for binding to oppositely charged ionic groups at the surface or a reactive group for forming a covalent bond with functional groups at the surface and/or for forming cross-links in the polymer coating.

Abstract: The invention provides an apparatus for coating tubular members, such as stents, and also provides a method for coating tubular members. The invention improves manufacturing efficiencies of existing manual-dipping technology for stents and also addresses manufacturing problems from stents having plural surface apertures associated with the presence of excess liquid, inconsistent drying of the liquid and blockage.