Cook Medical Technologies LLC

David Murray

John Neilan

James Butler

Christophe Silien

Syed A M Tofail

Rabah Mouras

Aladin Mani

Syed AM Tofail

A medical device such as a stent () or medical balloon () is at least partially coated with a saturated carboxylic acid layer in order to enhance biocompatibility, reduce thrombogenesis and increase endothelialisation. The coating is preferably of citric acid in non-crosslinked form and preferably non-porous so as to mask the underlying structure of the medical device. The acid coating forms an outer surface of at least a part of the medical device, that is has no other layer or material overlying it, save for in some embodiments a partial coating of a bioactive material.

Coated medical device and method of coating such a device

A method of modifying a surface of a medical device for implantation or disposition inside a patient is described. The medical device comprises a structure having at least one surface. The method includes the steps of: placing the medical device into a plasma chamber substantially free from contaminants and substantially sealing the plasma chamber from the atmosphere; removing at least an outermost layer of any oxide layer from the at least one surface of the structure by a plasma oxide-removal process, whilst maintaining the plasma chamber under seal from the atmosphere; and subsequently forming a new oxide layer at the least one surface of the structure by introducing at least one gas into the plasma chamber, whilst maintaining the plasma chamber under seal from the atmosphere. A medical device including a bulk material and an oxide layer disposed over at least one surface of the medical device. The oxide layer is substantially pure and free from contaminants.

Medical device with plasma modified oxide layer and method of forming such a device

There is disclosed a method of improving the reliability of coating an implantable medical device, such as a stent, with bioactive material in the absence of a carrier material such as a matrix or polymer layer. The method involves cleaning volatile components from the exposed surfaces of the medical device, removing carbon deposits and then applying a uniform carbon layer in a controlled environment. The deliberately applied carbon layer masks impurities of the underlying native oxide layer and leads to more uniform bioactive material coating not only a over the surfaces of a single medical device but also from device to device within a batch and between batches of devices. This improves production as well as optimising the amount and release of drug on the medical device without the need for a carrier material.

Regulation/modification of stent contact surface for polymer free drug coating

A medical device such as a stent or medical balloon is functionalised prior to coating with a bioactive material, specifically by carboxylic acidification of the contact surface or surfaces of the medical device. The preferred process involves washing a stent or other medical device in a washing solution which may be sodium hydroxide, soaking in a carboxylic acid solution, rinsing in water to remove excess carboxylic acid, allowing to dry before applying a bioactive agent layer. It has been found that washing after functionalisation removes excess carboxylic acid and enhances the retention of bioactive agent on the contact surface or surfaces of the medical device leading to a more uniform and consistent layer of bioactive agent.

Bioactive agent coated medical device and method of coating such a device

There are disclosed implantable medical devices and apparatus for treating implantable medical devices during production, so as to cause the implantable medical devices to have abluminal surfaces and luminal surfaces with different functional characteristics and in particular surface energies. The luminal surfaces of the medical device are preferably coated with carbon, so as to have a low surface energy, which reduces the risk of thrombi forming when implanted into a patient's vessels. The abluminal surfaces are treated so as to have a high surface energy, such that a therapeutic, preferably bioactive, material, such as a drug, can adhere to the abluminal surfaces and preferably without any need for a containment layer such as polymer or other matrix material. Once the therapeutic material has been delivered into the tissue wall, the stent can remain within the patient's vessel without leaving any delivery artefacts, as occurs with some prior art drug eluting medical devices.

Implantable medical device with differentiated luminal and abluminal characteristics

A medical device such as a stent () or medical balloon () is at least partially coated with a carboxylic acid layer in order to enhance biocompatibility, reduce thrombogenesis and increase endothelialisation. The coating is preferably of citric acid in non-crosslinked form and preferably non-porous so as to mask the underlying structure of the medical device. The acid coating forms an outer surface of at least a part of the medical device, that is has no other layer or material overlying it, save for in some embodiments a partial coating of a bioactive material.

A medical device such as a stent () or medical balloon () is functionalised prior to coating with a bioactive material (), specifically by acidification or basification of the contact surface or surfaces () of the medical device. Functionalisation with subsequent coating of bioactive agent directly onto the functionalised surface provides a significantly more consistent and reliable coating of bioactive agent on a medical device without requiring containment or time release devices.

The present invention generally relates to methods for determining the presence and distribution of a polarization active material present in a coating. In one embodiment, the coating is present on an implantable device, for example an implantable stent.

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Limerick, Ireland

David Murray