AU612161B2

AU612161B2 - Cleansing equipment for contact lenses

Info

Publication number: AU612161B2
Application number: AU19086/88A
Authority: AU
Inventors: Hans-Georg Hombach; Heinz Steinburg
Original assignee: Ciba Geigy AG
Current assignee: Novartis AG
Priority date: 1984-03-21
Filing date: 1988-07-15
Publication date: 1991-07-04
Anticipated expiration: 2005-03-13
Also published as: AU578936B2; EG17186A; EP0155505A1; DE3571203D1; ATE44239T1; AU3981385A; BR8501246A; DE3410400A1; DE3410400C2; EP0155505B1; AU1908688A; JPS60217333A; JPH0228849B2

Abstract

1. Contact lens maintenance kit, containing two solutions, of which one solution is a solution of hydrogen peroxide for cleansing and disinfecting the contact lens, and the other solution is an enzyme-containing neutralisation solution for the removal of residual hydrogen peroxide from the cleansed and disinfected lens, wherein the hydrogen peroxide solution is a from 0.5 to 3.0 % solution with protein- or lipoid-removing additives in the form of neutral electrolytes (NaCl, KCl, LiCl, sulfates, phosphates) and the neutralisation solution contains surface-active wetting agents in the form of soluble cellulose derivatives.

Description

Cornpany and 13ignatures of its Officers as prescribed bY ,it. Arti clea of Auociatio.

CIBA-GEIGY AG-.

T. A. Barnes Registered Patent Attorney To: rs' THE COMMISSIONER OF PATENI -7/ COMMONWEALTH OF AUSTRALIA Patents Act 1952 COMPLETE SPECIFICATION '6 1 2 1 6 1 (original) Class Int.

Class Application Number: Lodged: .*o*:omplete Specification Lodged: 4* 0 a* Accepted: 0 Published: 4860 ease.

a .0 so ?riority: 0:*6*elated Art: :::Name of Applicant: 0*101Address of Applicant: Actual Inventors: CIBA-GEIGY AKTIENGESELLSCHAFT, KLYBECKSTRASSE 141, 4002 BASLE, SWITZERLAND HANS-GEORG HOMBACH, AM TIEFEN WEG 16, 8786 KARLSTADT, FEDERAL REPUBLIC OF GERMANY; HEINZ STEINBURG, OSTEND 16, 5870 HEMER, FEDERAL REPUBLIC OF GERMANY -E*DTV--WAT&RS--&--S0N&, and Address for Service: 5OI-QUEEN--STR"1T--MEPL-BOtRNE-AUSTATA714O,fCLTHUrL S _0 7 C-c Complete Specification for the invention entitled: "CLEANSING EQUIPMENT F709- cc'p:thCr ~~e The following statement is a full description of this invention, inc- the best method of performing it known to us.

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CIBA-GEIGY AkU Ernst Altherr Single Signature, by special power 2.88 522 EA la The present invention relates to a maintenance kit for contact lenses, a method for taking care of contact lenses as well as cleaning equipment for this purpose.

Maintenance kits for soft and hard contact lenses serve for the cleansing, disinfecting, stabilizing of the optical properties and the improvement of comfort for the wearer of contact lenses.

In recent times, hydrogen peroxide as an antimicrobial substance has e*@ *gained in importance for the disinfection and cleansing of contact lenses. Compared with chlorhexidine salts or organic mercury 10 compounds, for example Thiomersal, which are also used for the disinfectior of contact lenses, hydrogen peroxide possesses a better antimicrobial activity, particularly with regard to the relatively resistant Aspergillus species. The known solutions o. hydrogen peroxide which are used in the cleansing of contact lenses have a 15 concentration of three percent of hydrogen peroxide. The result of this is that, after the treatment of the contact lenses with the hydrogen peroxide solution, there is still a relatively large amount left on the lenses which, after insertion of the contact lenses, leads to more or less severe irritation of the mucous membranes.

It is therefore necessary, after treating the lenses with the hydrogen peroxide solution, to treat the said lenses with a neutralizing solution which breaks down the hydrogen peroxide into water and oxygen. It is known that, for this purpose, metal catalysts such as platinum and palladium, or organic catalysts such as catalases, for example peroxidases (enzymes), or else organic sulphur-containing compounds or sulphides, may be used.

The recommended one amongst these methods is -'xidative enzymatic destruction of the peroxide. Any reducing agents which may be added actually remain in the solution and affect the tonicity so that it may become necessary to employ additional rinsing steps.

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0 2 The problem underlying the invention is therefore to provide a maintenance kit for contact lenses as well as a method of looking after the contact lenses along with suitable cleansing equipment for this purpose, which will allow for a reduction of the concentration of the hydrogen peroxide for the disinfection and cleansing of the contact lenses and ensure the removal of any residues of hydrogen peroxide which may still be present after the disinfecting and cleansing of the contact lenses, at least to a level which may be tolerated by the wearer of the lenses.

10 To solve this problem, the invention provides a contact lens maintenance kit which comprises a solvent set consisting of two solutions, one of which is a solution of hydrogen peroxide and the other is an enzyme-containing neutralization solution. In contrast to the known hydrogen peroxide solutions which are used for the care of contact lenses, the solution in accordance with the present invention has a lower concentration (0.5 which is preferably from 0.5 up to 2.0% or even up to It has been found that the killing of the micro-organisms by the lower concentrations of hydrogen peroxide in the solutions (down to 20 is in no way slower or less certain. In the case of Pseudomonas aeruginosa and Eschericha coli, the germs are killed in practically the same period of time as with solutions of higher concentrations. In the case of Candida albicans and Aspergillus niger, a period of time of two hours has proved to be sufficient for the killing of the germs.

Furthermore, the hydrogen peroxide solutions contain additives which, during storage of the lenses in the solution, increase their capability for removing proteins which may have become attached to the lenses. This is of particular importance for the cleansing of soft contact lenses. A similar effect may be achieved in the removal of lipoids from hard contact lenses.

Because it is the length of time of storage of the lenses in the hydrogen peroxide solution which largely influences the extent of removal of the proteins, it is recommended that the lenses, and in -3particular the soft lenses, should be allowed to remain overnight in the hydrogen peroxide solution.

Because 'of the decreased concentration (a decrease by a factor of 6 compared with the known hydrogen peroxide solutions used for cleansing of contact lenses), there is a smaller residual amount of hydrogen peroxide left on the treated lenses. Because of the smaller residual amount of hydrogen peroxide on the lenses, the subsequent neutralization treatment ensures a more certain removal of the hydrogen peroxide still adhering to the contact lenses. A time of 3 10 to 5 minutes is generally sufficient for the neutralization in order *99* to reduce any remaining hydrogen peroxide to a tolerable level. The absolutely certain removal of all traces of residual hydrogen peroxide would be guaranteed by a neutralization time of 10 minutes.

Because of the reduced concentration of hydrogen peroxide, there is 15 less attack on the contact lens material than there is with the conventional three percent solutions.

The neutralization solution contains surface-active wetting agents which, in contrast to the substances which have been in use for a long time now, are compatible with enzymes, in particular the 20 catalases. It has even been found, very surprisingly, that the stability of the enzymes (catalases) utilized in the neutralization solutions is actually increased.

The neutralization solutions may be kept free from preservatives, for use as which substances such as Thiomersal, sorbic acid and similar compounds have recently been proposed, which are very labile in solution and which require a relatively high concentration of at least 0.1%.

The neutralization solution employed in accordance with the invention is distinguished by the fact that it is a physiological saline solution which need not mandatorily contain preservatives but which contains a wetting agent, which is of particular importance in the treatment of hard contact lenses, and because the low co centration of enzyme leads to a rapid breakdown of the hydrogen r in i i -iliii-l*-*Y Y~LI*i 4 peroxide, that is to say to its splitting up into water and oxygen, it possesses an enzyme-stabilizing effect.

Preferably, a further component, in the form of cleansing equipment, is employed along with the maintenance-media set of the contact lens maintenance kit which, because of its simplicity and safety of manipulation, guarantees the reproducibility of the results and the preservation of the material from which the lenses are made during I* the performance of the cleansing and neutralization operations.

For reasons of comfort and compatibilty, modern contact lenses in oO* 10 recent years have been increasingly fabricated with ever smaller thickness in their central region. The materials for soft lenses which have increasingly come under consideration for some time now, and which have a higher water content, possess distinctly less resistance to mechanical stresses than do the conventional materials 15 for soft lenses.

*o To this must be added the fact that new hard lens materials have *as appeared on the market which have a relatively sensitive surface.

The preferable use of special cleansing equipment which has been recommended alongside the contact lens maintenance kit for the cleansing of contact lenses takes into account these weak points of conventional lens care by the standardisation of the mechanical cleansing process.

In contrast to the cleansing equipment which is known from the disclosure in the US-Patent 36 23 492, in the case of the cleansing equipment as described in Claim 1 of this present invention, the utilization of two maintenance solutions, which are applied in succession to the contact lenses, is facilitated. This is accomplished by having reference marks placed on the lid which is made up of two parts which may be rotated in relation to each other.

p ,L1,4 30 After the first stage of the treatment in which the hydrogen peroxide solution is allowed to act on the contact lenses, the two O parts of the lid can be rotated in relation to one another so that the single marks on each part of the lid are lying opposite to one another. This simplifies the manipulation by the user because this position of the parts of the lid indicates that the first stage of the treatment has already been completed. This means that there will be no confusion of the two stages of the treatment.

In addition to this, the operation of placing the contact lenses in the cleansing equipment is facilitated because of the articulated off arrangement of the carrier for the contact lenses since, in this manner, part of the contact lenis carrier, for example the central 10 portion of the carrier, may be arranged in the horizontal position S' or else it may be tilted into this position in order to receive the 0 contact lens. After the lens is placed in position the hinged cover may be closed down over the lens. Then, by swinging the carrier over through 1800, the other lens may be placed in position on the other 15 side of the contact lens carrier in a similar series of operations.

An example of embodiment of the cleansing equipment is illustrated in the accompanying diagrams. The invention is described in greater detail with reference to these diagrams. There is shown in Figure 1 20 a diagrammatic vertical section on the centre line through the example of embodiment of the cleansing equipment; Figure 2 a diagrammatic plan of the upper side of the lid of the equipment depicted in Figure 1; Figure 3 a diagrammatic vertical section on the centre line through the contact lens carrier.

The depicted example of embodiment of the cleansing equipment suitable for contact lenses which, as a component of a contact lens maintenance set, has a hydrogen peroxide solution for cleansing and disinfecting, and a neutralization solution for the removal of the residual hydrogen peroxide from the treated contact lenses, consists of a housing 1 into which the hydrogen peroxide solution and the neutralizing solution may be introduced successively, one after the other.

A contact lens carrier 2 (Figure 3) may be inserted into this housing 1 which is open at the top. A central carrier section 18 of the contact lens carrier 2 is depicted in Figure i. This central carrier section 18 possesses, as may be seen from Figure 3, outwardly curving spokes 27 between which the hydrogen peroxide S 10 solution or the neutralization solution, as the case may be, is able to flow freely. It is upon these curved spokes 27 that a contact lens 26 may be placed on either side of the central carrier section 18 as clearly shown in detail in Figure 3. There are hinged covers 19 on each side of the central carrier section 18 which are 15 articulated at the joints 20. The central carrier section 18 is, in its turn, pivotably mounted on a lens carrier holder 6 by means of the swivel joint 17.

0eS The lens carrier holder 6 is connected to a shaft 9 by means of a press-fit 12. The shaft 9 is supported in a watertight manner in a S. 20 lower portion 4 of the lid by means of a seal 5 (O-ring). The lower portion 4 of the lid is, by way of example, screwed down in a watertight manner onto the top of the housing 1 with the interposition of a flat sealing ring 7. There is a planetary drive consisting of a gearwheel 8 which meshes with a gearwheel 21 which is non-rotatably attached to the shaft 9 as well as with the ring gear provided on the inner surface of a rotatable portion 11 of the upper portion 3 of the lid.

The upper portion 3 of the lid also carries another portion 10 of the lid which, in the example of embodiment depicted, may be rotated in relation to the portion 11 of the lid. The portion 10 of the lid may also be non-rot-:.ably attached to the shaft 9.

In the treatment of the contact lenses with one of the two solutions, the upper portion 3 of the lid, or the rotatable portion 11 of the lid, may be rotated in relation to the lower portion 4 of 7 the lid which is fixed in position on the housing 1. This may be done manually. This rotation imparts a rotary motion to the gearwheel 8 and the gearwheel 21 as well as the shaft 9, and also the contact lens carrier 2 which projects downwards into the housing 1 as well as the lens carrier holder 6 which is non-rotatably attached to the shaft 9.

Since both of the hinged lids 19 which are articulated with the central carrier section 18 are also provided with ribs 23, as may be seen particularly clearly in Figure 3, there is, on the one hand, a 10 faultless supporting of the contact lenses on the central carrier 0*S* section 18 and, on the other hand, the particular solution being used at any time is able to flow freely through the hinged lids 19 so that the treatment solutions come into contact with the surfaces of the lenses. Under these conditions, with the rotation of the 15 contact lens carrier, which can be a reciprocating rotary motion, an I intensive treatment is achieved.

S* As may be seen from Figure 2, the upper portion 3 of the lid possesses reference markings 13, 15 and 14, 16 on its two opposingly rotatable sections 10 and 11. The markings 13 and 15 may be POP 20 allocated to the hydrogen peroxide solution and the pairs of markings 14 and 16 allocated to the neutralization solution. The markings are positioned in such a manner that they are opposite to one another in the two different relative positions of the rotatable portions 10 and 11. These two positions may be reached by the rotation of the portions 10 and 11 in opposite directions with respect to each other. The two portions 10 and 11 are configured in such a fashion that they will remain in the two given positions once they are placed there and they can only be be moved out of these end positions by the application of a definite torque. If, by way of example, the treatment with the hydrogen peroxide solution has been completed, the two portions 10 and 11 of the lid may be opposingly rotated so that the two markings 13 and 15 lie opposite to each other, as depicted in Figure 2. When the treatment with the neutralization solution has been completed, the two portions 10 and 11 of the lid iLay be opposingly rotated so that the pairs of markings 14 and 16 would come to lie opposite to each other.

8 8 During the insertion of the contact lenses into the contact lens carrier 2, the lid which consists of the upper portion 3 and the lower portion 4 is placed with its upper surface on a supporting surface and the contact lens carrier 2 is swung up around the joint 17 into a horizontal position (Figure The central carrier section 18 is then in the horizontal position and, in order to be e*g. able to insert the contact lens, the one hinged cover is lifted up as shown in Figure 3 and the contact lens is placed in position on the spoke-like ribs 17 of the central carrier section 18. The hinged 10 lid 19 is then lowered into the closed position and the contact lens carrier 18 is swung over through 1800 so that its other side is now in the top position where the contact lens may be placed on its spoke-like ribs after the hinged cover 19 has been lifted up. After inserting the lens the hinged cover 19 is lowered into the closed position again so that now both the contact lenses are securely housed in the contact lens carrier 18. Both the hinged covers possess a snap-fit locking device 24 at their outer ends which engages with an appropriate detent 25 on the end of the central carrier section 18. Thus the hinged covers cannot spring open during 20 the rotating movement of the lens carrier. Furthermore, when the see :hinged covers are in the closed position, the contact lenses are securely prevented from falling out from the carrier basket which is formed thereby.

In what follows, examples will be given for the ranges of the components of the hydrogen peroxide solution and the neutralization solution.

Hydrogen peroxide solution Hydrogen peroxide 0.5 up to less than 3.0 Complexing agent 0.01 2.0 edetic acid (di-sodium salt) nitrilotriacetic acid Primary sodium phosphate 0.1 1.0 9 Sodium di-phosphate and other poly-phosphates 0.1 5.0 Neutral electrolytes, e.g. NaCI, KC1, LiC1, sulphates, phosphates 0.2 up to 2.0 adjusted to pH value in the range 2 4 with phosphoric acid.

Neutralization solution SEnzymes (catalases or peroxidases) 10 500 U/ml *a Neutral electrolytes such as chloride, sulphate, phosphate, borate, citrate 0.2 1.5 Buffers such as phosphate, borate, citrate 0.2 1.0 a.

Soluble cellulose derivatives from the series Hydroxyethyl cellulose Methyl cellulose i: Methylhydroxypropyl cellulose Methylhydroxyethyl cellulose a Hydroxypropyl cellulose as enzyme stabilizer 0.02 0.5 and, if necessary appropriate preservatives compatible with the enzymes such as, e.g.

Chlorhexidine salts 0.5 5.0 mg/100 ml Thiomersal 1.0 5.0 mg/100 ml Sorbic acid 0.05 0.2 L- i

Claims

1. Cleansing equipment for use in a method for taking care of contact lenses, in which the contact lenses are treated first with a hydrogen peroxide solution for the removal of bacterial contamination and subsequently with a neutralization solution comprising a hydrogen peroxide decomposing enzyme for the removal of any residual hydrogen peroxide adhering to the contact lenses, characterized in that in the first step a solution comprising 0.5 up to less than 3.0 percent of hydrogen peroxide and containing protein- or lipoid-removing additives Sin the form of neutral electrolytes (NaC1,KCI,LiCl, sulphate, 9**e S phosphate) is employed, and that in the subsequent step a neutralization solution containing surface-active wetting ooo o agents in the form of soluble cellulose derivatives is employed, the cleansing equipment having a container which is Sopen at the top for receiving a treatment solution, a lid which o may be placed over the opening in the top of the container having planetary gears located within the said lid for the o •o rotation of a contact lens carrier which is pivotably fastened to a shaft, which is non-rotatably attached to the central *fe. gearwheel of the planetary gear, and which contact lens carrier is inserted down into the housing and this rotation is caused by the rotation of portion of the lid in relation to the housing, wherein the upper portion of the lid is divided up into two opposingly rotatable portions of the lid and each of the portions of the lid carries at least one reference marking for facilitating the utilisation of two maintenance solutions M =i employed, the cleansing equipment having a container which is open at the top for receiving a treatment solution, a lid which may be placed over the opening in the top of the container having planetary gears located within the said lid for the S./2 ~wu- 0210p:mmb *see. S. *0000 0000 0. 0 *SS*S S S eses S S SO *5 *SS S in succession, so that at least after the first treatment of the contact lenses in the hydrogen peroxide solution the two portions of the lid may be rotated into such a position in relation to each other that at least the one marking on the one portion of the lid is opposite to the other marking allocated to it on the other portion of the lid.

2. The.cleansing equipment according to claim 1, wherein the two opposingly rotatable portions of the lid each carries two reference markings.

3. The cleansing equipment according to claim 1 or 2, wherein the pivotable fastening of the contact lens ca_--ier to the shaft is accomplished by means of a joint to allow for the swinging over of the contact lens carrier through an angle of 180°

4. The cleansing equipment according to any or-' of the claims 1 to 3, wherein the contact lens carrier is provided with two hinged covers suitable for holding the contact lenses in -position and which are constructed in such a manner as to allow the solution contained in the housing to flow freely through them.

5. The cleansing equipment according to any one of the claims 1 to 4, wherein the two hinged covers are articulated with a central carrier portion.

6. Cleansing equipment for contact lenses substantially as hereinbefore described with reference to the accompanying drawings. DATED this 9th day of April, 1991. C-BA-GEIGY AG By I'ts Patent Attorneys ARTHUR S. CAVE CO. 'i^ ;e. arr \4V~~ ARTHUR S. CAVE CO.