Compositions and methods for inhibiting protein on surfaces

Abstract

The use of NIPAM polymers to prevent or reduce the formation of protein deposits on the surfaces of medical devices is described. The invention is particularly directed to reduction of the adsorption of proteins on surfaces of contact lenses and other medical prosthetics.

Description

BACKGROUND OF INVENTION[0001] The present invention is directed to the reduction of protein deposition on surfaces. The invention provides compositions and methods for inhibiting the deposition of protein on the surfaces of medical devices, particularly biomedical and prosthetic devices. The invention is based on the discovery that certain polymers and related copolymers comprising the monomer n-isopropylacrylamide (NIPAM) significantly inhibit protein deposition on the surfaces of contact lenses.[0002] Proteins adsorb to almost all surfaces and the minimization or elimination of protein adsorption has been the subject of numerous studies, such as those reported by Lee, et al., in J. Biomed. Materials Res., vol. 23, pages 351-368 (1989). Sensors, chromatographic supports, immunoassays, membranes for separation, biomedical implants, prosthetic devices (e.g., contact lenses) and many other devices or objects can be adversely affected by protein adsorption. A method and / or means for tr...

AI Technical Summary

Benefits of technology

[0026] Although not wishing to be bound by theory it is believed that the NIPAM polymers described herein have a range of inherent physical properties (e.g., low interfacial free energy, hydrophilic-hydrophobic properties, very low toxicity, dynamic surface mobility and steric stabilization) that enable these polymers to exhibit superior protein inhibiting characteristics.

[0035] The compositions of the present invention that are intended for use as CLC products will contain one or more ophthalmically acceptable antimicrobial agents in an amount effective to prevent microbial contamination of the compositions (referred to herein as "an amount effective to preserve"), or in an amount effective to disinfect contact lenses by substantially reducing the number of viable microorganisms present on the lenses (referred to herein as "an amount effective to disinfect").

Problems solved by technology

Sensors, chromatographic supports, immunoassays, membranes for separation, biomedical implants, prosthetic devices (e.g., contact lenses) and many other devices or objects can be adversely affected by protein adsorption.

Soft lenses typically contain a large amount of water, are quite porous, and bear ionic charges on the exposed surfaces of the lenses, while hard lenses are considerably less porous and generally do not bear ionic surface charges.

The ionic surfaces and porous nature of soft contact lenses can lead to significant problems when the lenses come into contact with the tear film due to the complex composition of the tear film, which is largely comprised of proteins, lipids, enzymes and various electrolytes.

The uptake of proteins from the tear fluid onto the lens is a common problem and depends on a number of factors, including the nature of the materials from which the lens is made.

This fouling can lead to dehydration of the lens and instability of the tear film, resulting in discomfort and lack of tolerance in the wearer.

Adsorption of proteins can also facilitate bacterial colonization and this can increase the risk of vision-threatening infections.

However, the use of these agents can lead to irritation, and in cases where rubbing and cleaning regimens are required, there is a possibility that the cleaning agents will not be used properly or will be used in a manner that damages the lenses.

These prior attempts to reduce protein binding have drawbacks.

Additionally, due to the positive charge character of these macromolecules, complex formation with anionic surfactants or other components of CLC products may lead to flocculation and phase separation in the formulation, which is a significant problem.

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