Contact lens solution and related systems and methods

Abstract

Disclosed herein are various embodiments relating to a contact lens treatment that provides significantly improved wetting properties of physical surfaces, such as the surfaces of contact lenses, although other surfaces could be treated with the same treatment for similar effects. These embodiments use oppositely charged particles to ensure a high degree of surface wetting.

Description

CONTACT LENS SOLUTION AND RELATED SYSTEMS AND METHODSCROSS-REFERENCES & RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Application 63 / 704,403, filed October 7, 2024, and entitled “Contact Lens Solution and Related Systems and Methods,” each of which is hereby incorporated herein by reference in its entirety.TECHNICAL FIELD

[0002] The disclosure relates to personal care products generally and contact lens solution specifically.BACKGROUND

[0003] Approximately 44 million contact lens wearers in the USA and 76% of wearers complain of dryness. In the clinic, non-wetting gas permeable (GP) trial lenses in clinic are stored dry, and therefore have non- wetting surfaces during contact lens fittings. Non- wetting lenses increase chair time and decrease the patient experience. Additionally, non-wetting lenses remain an issue for the patient during habitual GP and soft contact lens wear. This dry surface can cause refractory distortions and irritate the underlying tissue of the ocular surface and eyelids. Current strategies to address this issue have been inadequate and include various eye drops and surface modifications. Contact lens non-wetting, deposits, and dryness, together, are the greatest complaint among contact lens wearers. Accordingly, there is a need in the art for a material, method, or system that can alleviate the sensation of dryness experienced by many users of contact lenses.BRIEF SUMMARY OF THE INVENTION

[0004] Disclosed herein are various embodiments relating to a contact lens treatment that provides significantly improved wetting properties of physical surfaces, such as the surfaces of contact lenses. These embodiments use oppositely charged particles to ensure a high degree of surface wetting.

[0005] In certain embodiments, the present disclosure relates to ophthalmic compositions and methods for improving the surface wetting and lubricity of contact lenses, particularly gas#4933327permeable lenses. In various embodiments, the invention provides a contact lens solution comprising a buffered saline vehicle, a positively charged hydrophilic polymer dissolved in the vehicle, and an ocular-compatible surfactant. The solution enhances the affinity of aqueous media for lens surfaces and reduces contact angle, thereby improving comfort, handling, and on- eye performance.

[0006] In certain embodiments, the positively charged hydrophilic polymer comprises a polyacrylamide. The polyacrylamide can exhibit a molecular weight of at least about 1,000,000 g / mol, including embodiments where the molecular weight ranges from about 1,000,000 to about 20,000,000 g / mol, from about 5,000,000 to about 15,000,000 g / mol, or is about 10,000,000 g / mol. In further embodiments, the polyacrylamide has a charge density of at least 20%, including about 20% to about 40%, and in particular about 30%. The buffered saline vehicle can further include one or more ocular-compatible surfactants. In certain embodiments, the surfactant comprises ethoxylated sorbitan monooleate, which can be present at about 0.12% w / v.

[0007] The compositions disclosed herein arc effective to significantly reduce the apparent contact angle exhibited by lens surfaces when challenged with an aqueous medium. In some embodiments, applying the solution to a gas permeable contact lens yields a contact angle with balanced salt solution from about 0° to about 5°, and in particular about 0°. In method embodiments, applying a solution comprising a buffered saline vehicle, an ocular-compatible surfactant, and a positively charged polyacrylamide having a molecular weight from about 5,000,000 to about 15,000,000 g / mol to a gas permeable contact lens enhances lens lubricity and wetting, including reductions in contact angle of at least about 70% relative to a comparable lens treated with buffered saline lacking the positively charged polyacrylamide.

[0008] These compositions and methods provide durable wetting and improved lubricity to contact lens surfaces while maintaining ocular compatibility and ease of use. The invention encompasses the foregoing compositions, parameters, and performance outcomes individually and in any operative combination, as set forth in the claims.

[0009] While multiple embodiments are disclosed, still other embodiments of the disclosure will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. As will be realized, the disclosure is capable of modifications in various obvious aspects, all without departing from the spirit andscope of the disclosure. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive.BRIEF DESCRIPTION OF DRAWINGS

[0010] FIG. 1 is a goniometer image showing a saline solution on a contact lens surface.

[0011] FIG. 2 is a goniometer image showing a saline solution on a contact lens surface that has been treated with a prior art product.

[0012] FIG. 3 is a goniometer image showing a saline solution on a contact lens surface that has been treated with a disclosed formulation, according to one implementation.

[0013] FIG. 4 is a table summarizing the contact angles measured in the goniometer images.DETAILED DESCRIPTION

[0014] Before the present compounds, compositions, articles, systems, devices, and / or methods are disclosed and described, it is to be understood that they are not limited to specific synthetic methods unless otherwise specified, or to particular reagents unless otherwise specified, as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, example methods and materials are now described.

[0015] Ranges can be expressed herein as from “about” one particular value, and / or to “about” another particular value. When such a range is expressed, a further aspect includes from the one particular value and / or to the other particular value. Similarly, when values arc expressed as approximations, by use of the antecedent “about,” it will be understood that the particular value forms a further aspect. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint. It is also understood that there are a number of values disclosed herein, and that each value is also herein disclosed as “about” that particular value in addition to the value itself. For example, if the value “10” is disclosed, then “about 10” is also disclosed. It is also understood that each unit between two particular units are also disclosed. For example, if 10 and 15 are disclosed, then 11, 12, 13, and 14 are also disclosed.

[0016] As used herein and in the claims, the term "about" when modifying a numerical value or range indicates that the value or range includes variations that arise from measurement error and acceptable manufacturing tolerances. Unless otherwise specified, "about" means within ±10% of the stated value or the endpoints of a stated range; however, in appropriate contexts (for example, pH, concentration, or contact angle), "about" can correspond to a smaller tolerance, such as within ±5% or within an absolute increment that a person of ordinary skill in the art would deem reasonable in view of the particular measurement and its significant figures.

[0017] As used herein, the term “substituted” is contemplated to include all permissible substituents of organic compounds. In a broad aspect, the permissible substituents include acyclic and cyclic, branched and unbranched, carbocyclic and heterocyclic, and aromatic and nonaromatic substituents of organic compounds. Illustrative substituents include, for example, those described below. The permissible substituents can be one or more and the same or different for appropriate organic compounds. For purposes of this disclosure, the heteroatoms, such as nitrogen, can have hydrogen substituents and / or any permissible substituents of organic compounds described herein which satisfy the valences of the heteroatoms. This disclosure is not intended to be limited in any manner by the permissible substituents of organic compounds. Also, the terms “substitution” or “substituted with” include the implicit proviso that such substitution is in accordance with permitted valence of the substituted atom and the substituent, and that the substitution results in a stable compound, e.g., a compound that does not spontaneously undergo transformation such as by rearrangement, cyclization, elimination, etc. It is also contemplated that, in certain aspects, unless expressly indicated to the contrary, individual substituents can be further optionally substituted (i.e., further substituted or unsubstituted).

[0018] Certain materials, compounds, compositions, and components disclosed herein can be obtained commercially or readily synthesized using techniques generally known to those of skill in the ait. For example, the starting materials and reagents used in preparing the disclosed compounds and compositions are either available from commercial suppliers such as Aldrich Chemical Co., (Milwaukee, Wis.), Acros Organics (Morris Plains, N.J.), Fisher Scientific (Pittsburgh, Pa.), or Sigma (St. Louis, Mo.) or are prepared by methods known to those skilled in the art following procedures set forth in references such as Fieser and Fieser’s Reagents for Organic Synthesis, Volumes 1-17 (John Wiley and Sons, 1991); Rodd’s Chemistry of Carbon Compounds, Volumes 1-5 and Supplemental (Elsevier Science Publishers, 1989); OrganicReactions, Volumes 1-40 (John Wiley and Sons, 1991); March’s Advanced Organic Chemistry, (John Wiley and Sons, 4th Edition); and Larock’s Comprehensive Organic Transformations (VCH Publishers Inc., 1989).

[0019] Lubricity refers to the ability of a substance to reduce friction between surfaces in relative motion under load. It is a measure of the effectiveness of a lubricant in minimizing wear and preventing direct contact between opposing surfaces. Contact lens lubricity refers to the ability of a contact lens to remain moist and slippery on the surface, allowing for smooth movement over the eye and for smooth movement of the eyelid over the contact lens. This is an important factor in contact lens comfort, as lenses that lack lubricity can cause discomfort, dryness, and irritation. Lubricity also affects the ability of the lens to resist deposits and maintain clarity.

[0020] Several factors can influence contact lens lubricity, including the type of material used, the surface treatment of the lens, and the presence of certain additives. Manufacturers may incorporate lubricating agents into the lens material or apply surface coatings to enhance lubricity.

[0021] Disclosed are the components to be used to prepare the compositions of the invention as well as the compositions themselves to be used within the methods disclosed herein. These and other materials are disclosed herein, and it is understood that when combinations, subsets, interactions, groups, etc. of these materials are disclosed that while specific reference of each various individual and collective combinations and permutation of these compounds cannot be explicitly disclosed, each is specifically contemplated and described herein. For example, if a particular compound is disclosed and discussed and a number of modifications that can be made to a number of molecules including the compounds arc discussed, specifically contemplated is each and every combination and permutation of the compound and the modifications that are possible unless specifically indicated to the contrary. Thus, if a class of molecules A, B, and C are disclosed as well as a class of molecules D, E, and F and an example of a combination molecule, A-D is disclosed, then even if each is not individually recited each is individually and collectively contemplated meaning combinations, A-E, A-F, B-D, B-E, B-F, C-D, C-E, and C-F are considered disclosed. Likewise, any subset or combination of these is also disclosed. Thus, for example, the sub-group of A-E, B-F, and C-E would be considered disclosed. This concept applies to all aspects of this application including, but not limited to, steps in methods of making and using the compositions of the invention. Thus, if there are a variety of additional steps thatcan be performed it is understood that each of these additional steps can be performed with any specific embodiment or combination of embodiments of the methods of the invention.

[0022] As used herein, the term “substantially” refers to the complete or nearly complete extent or degree of an action, characteristic, property, state, structure, item, or result. For example, an object that is "substantially" enclosed would mean that the object is either completely enclosed or nearly completely enclosed. The exact allowable degree of deviation from absolute completeness may in some cases depend on the specific context. However, generally speaking the nearness of completion will be so as to have the same overall result as if absolute and total completion were obtained. The use of “substantially” is equally applicable when used in a negative connotation to refer to the complete or near complete lack of an action, characteristic, property, state, structure, item, or result. For example, a composition that is "substantially free of particles” would either completely lack particles, or so nearly completely lack particles that the effect would be the same as if it completely lacked particles. In other words, a composition that is “substantially free of an ingredient or element may still actually contain such item as long as there is no measurable effect thereof.

[0023] Aqueous and aqueous solution mean that water is present but does not require that water be the predominant component. For purposes of illustration and not in limitation, a solution of 90 volume percent of ethylene glycol and 10 volume percent water would be an aqueous solution. Aqueous solutions include liquid media containing dissolved or dispersed components such as, but not in limitation, colloidal suspensions and slurries.

[0024] In various embodiments, a treatment solution may be used on a surface, such as a contact lens. In these various embodiments, it is desirable for the treatment solution, as well as subsequently introduced solutions, to have high affinity to the surface so the solutions adhere to the surface, rather than beading against the surface due to surface tension of the solutions. In some embodiments, the surfaces are gas permeable contact lenses that are non-wetting. As would be understood, gas permeable lenses are stored dry, rather than in saline solution or the like. As the gas permeable lenses are dry, their dry surfaces can cause refractory distortions and irritate the tissue of the ocular surface and eyelids, once inserted into the eye.

[0025] In various embodiments, acrylamide is used as a base polymer in a formulation of the treatment solution. In some specific embodiments, the acrylamide is a cationic polyacrylamide.As contact lens surfaces typically have a partial negative charge, the positive charge of the cationic polyacrylamide increases the affinity of the treatment solution to the contact lens.

[0026] The primary component of the contact lens solution is a buffered saline solution. The buffer helps maintain the pH within a range that is compatible with ocular tissues, ensuring that the solution is gentle on the eyes. In various embodiments, the pH of the disclosed contact lens solution can be within 1.0 to 1.5 pH units from physiological pH, particularly the physiological pH in the external environment of the eye. The pH of human tears is approximately pH 7.4. Hence, the pH of the ophthalmic solution can be about 1.0 to 1.5 pH units above or below pH7.4. In some embodiments, the pH of the ophthalmic solution is from about pH 6.0 to about pH8.5. In some embodiments, the pH of the ophthalmic solution is from about pH 6.0 to about pH8.0. In some embodiments, the pH of the ophthalmic solution is from about 6.5 to about 8.0. In some embodiments, the pH of the ophthalmic solution is from about 7.0 to about 8.0. In some embodiments, the pH of the ophthalmic solution is from about 7.0 to about 7.5. In some embodiments, the pH of the ophthalmic solution is about 6.5, about 7, about 7.5, about 8, or about 8.5. A person of skill in the art can select a pH that balances the stability of the ophthalmic solution and the tolerability of the eye to differences in pH from the natural condition. As is well known in the art, the pH of the solution can be adjusted by use of appropriate buffering agents and / or with an appropriate base (e.g., sodium hydroxide) or acid (e.g., hydrochloric acid). Generally, buffer capacities of from about 0.01 to 0.1 can be used for ophthalmic solutions, particularly at concentrations that provide sufficient buffering capacity and minimizes adverse effects, e.g., irritation, to the eye. Exemplary buffering agents include, by way of example and not limitation, various salts (e.g., sodium, potassium, etc.), acids or bases, where appropriate, of the following agents, including, among others, acetate, borate, phosphate, bicarbonate, carbonate, citrate, tetraborate, biphosphate, tromethamine, hydroxyethyl morpholine, and THAM(trishy droxymethylamino-methane). In some embodiments, the buffering agent can be present from about 0.01 mM to about 100 mM, about 0.05 mM to about 100 mM, about 0.5 mM to about 100 mM, from about 1 mM to about 50 mM, from about 1 mM to about 40 mM, from about 1 mM to about 30 mM, from about 1 mM to about 20 mM, or from about 1 mM to about 10 mM. In some embodiments, the buffering agent can be present at about 0.01 mM, about 0.05 mM, about 0.1 mM, about 0.2 mM, about 0.5 mM, about 1 mM, about 5 mM, about 10 mM, about 20 mM, about 30 mM, about 40 mM, about 50 mM, or about 100 mM.

[0027] In some embodiments, an exemplary buffering agent is phosphate, particularly sodium phosphate, which can be prepared by standard procedures, for example by mixing appropriate amounts of one or more monobasic phosphates, dibasic phosphates, and the like. In particular, useful phosphate buffers are prepared from phosphate salts of alkali and / or alkaline earth metals, such as sodium or potassium phosphate, including sodium monobasic phosphate, sodium dibasic phosphate, potassium monobasic phosphate, and potassium dibasic phosphate. In some embodiments, the phosphate buffer can be present from about 0.5 mM to about 100 mM, from about 1 mM to about 50 mM, from about 1 mM to about 40 mM, from about 1 mM to about 30 mM, from about 1 mM to about 20 mM, or from about 1 mM to about 10 mM. In some embodiments, the phosphate buffer can be present at about 0.5 mM, about 1 mM, about 5 mM, about 10 mM, about 20 mM, about 30 mM, about 40 mM, about 50 mM, or about 100 mM.

[0028] The key additive in the solution is a positively charged hydrophilic polymer, which interacts with the contact lens material to enhance its lubricity.

[0029] In one embodiment, the positively charged polymer is a polyacrylamide. This polymer has been found to be particularly effective in increasing the lubricity of contact lenses. In certain embodiments, the polyacrylamide polymer has a molecular weight of at least about 1,000,000 g / mol. In still further embodiments, the polyacrylamide has a molecular weight ranging from about 1,000,000 to about 20,000,000 g / mol. In yet further embodiments, the polyacrylamide has a molecular weight from about 5,000,000 to about 15,000,000 g / mol. In even further embodiments, the polyacrylamide has a molecular weight of about 10,000,000 g / mol.

[0030] In certain embodiments, the polyacrylamide polymer possesses a charge density of at least 20%. Preferably, the charge density ranges from about 20% to about 40%. In a specific embodiment, the polyacrylamide has a charge density of about 30%.

[0031] In some embodiments, the contact lens solution contains polyacrylamide at a concentration greater than 0.1% w / v, for example, about 0.11% w / v to about 0.5% w / v, about 0.12% w / v to about 0.5% w / v, about 0.13% w / v to about 0.5% w / v, about 0.14% w / v to about 0.5% w / v, about 0.15% w / v to about 0.5% w / v, about 0.16% w / v to about 0.5% w / v, about 0.17% w / v to about 0.5% w / v, about 0.18% w / v to about 0.5% w / v, about 0.19% w / v to about 0.5% w / v, about 0.2% w / v to about 0.5% w / v, about 0.25% w / v to about 0.45% w / v, or about 0.3% w / v to about 0.4% w / v.

[0032] The buffered saline solution may further include one or more ocular surfactants. Examples of suitable surfactants include surfactants such as ethoxylated sorbitan monoolcatc. In certain embodiments, the buffered saline solution contains ethoxylated sorbitan monooleate in an amount from about 0.06% w / v to about 0.18% w / v. In further embodiments, the buffered saline solution contains ethoxylated sorbitan monooleate in an amount of about 0.12% w / v.

[0033] When the contact lens solution is applied as a pretreatment to the surface of a gas permeable contact lens, it results in the contact lens having a contact angle with balanced salt solution ranging from about 0° to about 5°. Preferably, the gas permeable contact lens has a contact angle with balanced salt solution of about 0°.

[0034] While the contact lens solution is preferably formulated as ready to use aqueous solutions i.e., solution which does not require any dilution or preparation before use, alternative formulations can be used. For example, the contact lens solution can be provided in a lyophilized or as a dried powder or solid form ready for reconstitution with a solvent, such as sterile water (e.g., deionized or distilled) or buffer solution. In some embodiments, the contact lens solution is pyrogen and / or endotoxin free. In various embodiments, the disclosed solution can be prepared by appropriate sterilization procedures known in the art. In some embodiments, the cationic polymer or derivative thereof is produced under sterile conditions, and the mixing and packaging is conducted under sterile conditions. In some embodiments, the compositions of may be filter- sterilized and filled in vials, including unit dose vials providing sterile unit dose formulations. In some embodiments, the composition and / or agents of the compositions are sterilized by steam, y- radiation, or by appropriate chemical sterilization procedures.

[0035] In certain embodiments, the instantly disclosed solution can be for non-ocular medical applications. Exemplary implementations of these medical applications include enabling smoother intubations, maintaining hydration of tracheostomy tubes or endotracheal tubes, nasotracheal intubations, lubricity for urethral catheters, and / or any intervention that contacts mucus membranes.

[0036] Although the disclosure has been described with reference to preferred embodiments, persons skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the disclosed apparatus, systems and methods.EXAMPLES

[0037] The following examples arc put forth so as to provide those of ordinary skill in the art with a complete disclosure and description of how the compounds, compositions, articles, devices and / or methods claimed herein are made and evaluated and are intended to be purely exemplary of the invention and are not intended to limit the scope of what the inventors regard as their invention. However, those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments which are disclosed and still obtain a like or similar result without departing from the spirit and scope of the invention.

[0038] Example 1 - Cationic Polyacrylamide

[0039] In this example, one specific embodiment was tested for efficacy in alleviating dryness of contact lenses.

[0040] Acrylamide was used as the base polymer for this example, due to its hyperhydrophilicity, chemical modifiability, and established biological safety profile. A cationic polyacrylamide of high positive charge per repeat unit and >1,000,000 g / mol molecular weight was added to buffered saline solution with a standard ophthalmic concentration of ocular surfactant (ethoxylated sorbitan monooleate) and applied to contact lenses.

[0041] The wetting properties, persistence on the lens, and subjective lubricity of the cationic polyacrylamide-based formulation were found to be superior to commercially available lens lubricants or saline alone. When this cationic polyacrylamide -based solution was mechanically applied by gentle rubbing onto the surface, the lenses were found to exhibit an unmeasurable contact angle and superior wetting, even after repeated washing in sterile saline solution.

[0042] As would be understood, an increase in wetting properties of a solution results in a lower contact angle of a drop of the solution against a surface. FIG. 1 shows the contact angles of a 10 pL of balanced salt solution on a factory polished and plasma cleaned gas permeable contact lens button surface. As can be seen, the contact angles are 85° and 94°, which are indicative of poor wetting properties. FIG. 2 shows the contact angles of a 10 pL of balanced salt solution on the same surface, but where the surface has first been treated with Simplus, a prior-art care product. The Simplus pretreatment reduces the contact angles to 47° and 43°.

[0043] FIG. 3 shows the contact angles of a 10 pL drop of balanced salt solution on the same surface, but where the surface has first been treated with the presently disclosed formulation, referred to as Revity. This formulation increased the wetting properties of the solution sodrastically that no contact angle could be measured, yielding an effective contact angle of 0°. FIG. 4 summarizes these contact angle measurements.

[0044] The lens was still handleable but had much improved lubricity. The desired wetting and persistence properties only emerged with high cationic charges and a minimum threshold concentration of cationic polyacrylamide; lower cationic charges on the polyacrylamide or surfactant alone, yielded a transient film with imperfect wetting properties.

Claims

CLAIMSWhat is claimed is:

1. A contact lens solution for enhancing contact lens lubricity comprising: a. a buffered saline solution; b. a positively charged hydrophilic polymer dissolved within the buffered saline solution.; and c. an ocular-compatible surfactant dissolved within the buffered saline solution2. The solution of claim 1, wherein the positively charged polymer is a polyacrylamide.

3. The contact lens solution of claim 2, wherein the polyacrylamide has a molecular weight of at least about 1,000,000 g / mol.

4. The contact lens solution of claim 3, wherein the polyacrylamide has a molecular weight of from about 1,000,000 to about 20,000,000 g / mol.

5. The contact lens solution of claim 4, wherein the polyacrylamide has a molecular weight of from about 5,000,000 to about 15,000,000 g / mol.

6. The contact lens solution of claim 5, wherein the polyacrylamide has a molecular weight has a molecular weight of about 10,000,000 g / mol.

7. The contact lens solution of claim 1, wherein the polyacrylamide has a charge density of at least 20%.

8. The contact lens solution of claim 7, wherein the polyacrylamide has a charge density of from about 20% to about 40%.

9. The contact lens solution of claim 8, wherein the polyacrylamide has a charge density of about 30%.

10. The contact lens solution of claim 1, wherein the buffered saline solution further comprises one or more ocular surfactant.

11. The contact lens solution of claim 10, wherein the one or more ocular surfactant is ethoxylated sorbitan monooleate and wherein the ethoxylated sorbitan monooleate is present in an amount of about 0.12% w / v of the solution.

12. The contact lens solution of claim 1, wherein upon application of the contact lens solution to a gas permeable contact lens, the gas permeable contact lens has a contact angle of from about 0° to about 5°.

13. The contact lens solution of claim 12, wherein the gas permeable contact lens has a contact angle with balanced salt solution of about 0°.

14. A solution for enhancing contact lens lubricity comprising: a. a buffered saline solution; b. an ocular-compatible surfactant dissolved within the buffered saline solution; c. a positively charged polyacrylamide polymer with a molecular weight of from about 5,000,000 to about 15,000,000 g / mol dissolved within the buffered saline solution, wherein the polyacrylamide has a charge density of from about 20% to about 40%.

15. The contact lens solution of claim 14, wherein upon application of the contact lens solution to a gas permeable contact lens, the gas permeable contact lens has a contact angle with balanced salt solution of from about 0° to about 5°.

16. The contact lens solution of claim 15, wherein the polyacrylamide has a charge density of about 30%.

17. A method of enhancing lubricity of a gas permeable contact lens, the method comprising: applying a contact lens solution to the gas permeable contact lens wherein the contact lens solution comprises: a buffered saline solution; an ocular-compatible surfactant dissolved within the buffered saline solution; and a positively charged polyacrylamide polymer with a molecular weight of from about 5,000,000 to about 15,000,000 g / mol g / mol dissolved within the buffered saline solution.

18. The method of claim of claim 17, wherein the polyacrylamide has a charge density of from about 20% to about 40%.

19. The method of claim 17, wherein application of the contact lens solution to the gas permeable contact lens results in a decrease in contact angle of the lens of at least about 70% relative to a comparable gas permeable contact lens treated with a buffered saline solution without positively charged polyacrylamide.

20. The method of claim 19, wherein the gas permeable contact lens has a contact angle of from about 0° to about 5°.

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