Biocompatible self-lubricating polymer compositions and their use in medical and surgical devices

Abstract

The invention comprises self-lubricating polymer compositions that are especially useful in medical devices and valves and gaskets of medical devices. In a preferred embodiment, the polymer compositions comprise a thermosetting or thermoplastic silicone elastomer in combination with a lubricity enhancing polyfluoropolyether fluid or hydrocarbon-based synthetic oil. In other preferred embodiments, the polymer compositions contain only biocompatible components. The improved anti-friction properties of the self-lubricating polymers can be demonstrated over a course of insertion and withdrawal cycles, where conventional polymers have changing and mostly increasing force required for each insertion and withdrawal, while the polymer compositions of the invention remain stable.

Description

[0001]This application claims priority benefit of U.S. provisional application 60 / 795,593 filed on Apr. 28, 2006, the entire contents of which are incorporated herein by reference.FIELD OF THE INVENTION[0002]The invention relates to polymer compositions with enhanced anti-friction properties for use in medical applications and medical devices. The polymer compositions have reduced friction characteristics and can be implemented in tubing, gaskets, valves, and in a variety of insertion devices and other devices used in procedures to introduce objects into the body, for example.INTRODUCTION, RELATED ART AND BACKGROUND TO THE INVENTION[0003]A growing number of surgical or medical procedures employ devices and kits that rely on inserting a device or tube through a sealed valve or apparatus. For example, catheters and guides are typically inserted through a sterile valve to introduce fluids, intraluminal devices and many other instruments into the body or into the lumen of a blood vessel...

AI Technical Summary

Benefits of technology

[0007]In another general aspect, the invention provides self-lubricating or enhanced lubricity polymer compositions for use in medical and surgical devices and related applications. The term lubricity is used in the conventional sense of a lubricating characteristic that effectively reduces friction between rubbing or contact surfaces. Lubricity can be most important in conditions of boundary lubrication and/or for continuously maintaining a low surface-energy and/or to effectively repel body fluids and the resulting drag forces on contact surfaces. By increasing the lubricity of the polymer material used, the degree of deformation can be limited for a particular structure to form or maintain a leak-proof seal, while the force needed to slide over or through the structure is reduced. A preferred example of a self-lubricating polymer composition comprises a biocompatible elastomer, and especially preferred is a biocompatible silicone elastomer. Other biocompatible blends of elastomers and/or thermoplastic polymers can also be used, as known in the art. The self-lubricating compositions also comprise one or more lubricants, such as synthetic oils and/or solid lubricants. Preferred synthetic oil lubricants are polyfluoropolyether (PFPE) synthetic oils, polytetrafluoroethylene (PTFE) synthetic oils, and hydrocarbon-based synthetic oils, namely co-oligomers of ethylene and olefins. Preferred solid lubricants include low molecular weight polytetrafluoroethylene powders, titanium dioxide micropowders, molybdenum disulfide micropowders, graphite micropowders or flakes, and baron nitride micropowders and the like. Any combination of these lubricants and others available and/or used in the art for biocompatible materials can be selected, and preferred combinations are given in the Examples.

[0008]As noted above, the self-lubricating polymer compositions can be used to produce one or more parts or elements in a medical or surgical device. In one preferred example, the part or element can comprise all or part of an insertion device or a receiving area for an inserted device or other elongated medical device. Typically, a receiving area employs a gasket or seal, which can readily and/or repeatedly permit passage of one or more devices, optionally of varying diameters. The gasket or seal or other receiving area is comprised of the polymer composition of the invention and thus has improv...

Problems solved by technology

However, pliable or flexible polymers tend to cause a degree of friction when an element is inserted or withdrawn into or through them.

During medical or surgical procedures, this friction is undesirable and may lead to a lack of control and require forceful insertion or withdrawal.

Some kits and procedures even require multiple guidewire and catheter exchange steps, for example, w...

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