Classifications

• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
  • C11D3/0005—Other compounding ingredients characterised by their effect
  • C11D3/0078—Compositions for cleaning contact lenses, spectacles or lenses
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
  • C11D3/16—Organic compounds
  • C11D3/38—Products with no well-defined composition, e.g. natural products
  • C11D3/386—Preparations containing enzymes, e.g. protease or amylase
  • C11D3/38627—Preparations containing enzymes, e.g. protease or amylase containing lipase

Definitions

• the present invention relates to methods and materials for removing from soft contact lenses deposits that are formed during use.
• Such deposits contain mainly Albumin, Globulins and Lipids.
• Deposits that occur during use of soft contact lenses generally result in an opaque film, yellow discoloration, white spots and thread-like configurations on the lenses. Investigations carried out have shown that these deposits can consist of Albumin, Ig ⁇ -Globulin, Lysozyme and lipoproteins.
• the deposits are often largely composed of Lipids and denatured Albumin, which are deposited on the lenses from the tear fluid as a result of the saline solution with which the lenses are impregnated being exchanged for the tear fluid.
• the drying-cut of a lens for instance through its use in a dry environment and by air flowing past it, etc. causes some Albumin to be denatured and deposited on the lens.
• Albumin is denatured which gives rise to apolar interior groups of Lipids.
• Other causes too such as for example continuous use, cause Albumin and Lipids to be deposited on contact lenses in fairly large quantities.
• One method of cleaning contact lenses is already known which comprises the steps of dissolving in water a proteolytic enzyme in tablet form and then placing the lenses to be cleaned in the solution for a period of ar least two hours.
• This process has been regarded as complicated by the wearers of contact lenses so that cleaning has not always been carried out as regularly as is required and this has resulted in lenses finally acquiring such a coating that the lunses have become unusable.
• the prior art using only proteolyte enzymes does not provide for complete removal of the deposits formed in that deposits of lipid origin remain substantially unaffected by the solutions of the prior art.
• An object of the present invention is to provide cleaning solutions and methods for cleaning soft contact lenses which, on the one hand are simple for the contact lens wearer to use and which also provide an improved cleaning effect.
• Yet another object of the present invention is to provide solid compositions of matter to be dissolved in an aqueous vehicle to form soft contact lens cleaning solutions, preferably of a hypertonic character.
• an enzyme containing cleaning liquid for soft contact lenses consists of a solution containing a lipolytic enzyme (mainly for reducing the lipids) and, optionally, a proteolytic enzyme, such as papain or bromelain, (for reducing the Albumin deposits) and, additionally, a buffering agent, such as a phosphate.
• a lipolytic enzyme mainly for reducing the lipids
• a proteolytic enzyme such as papain or bromelain
• a buffering agent such as a phosphate.
• Such cleaning liquid is preferably hypertonic to its nature, i.e. its osmotic pressure exceeds that of a physiological solution, so that in treatment with the solution some dewatering of the lens takes place, which seems to be beneficial to the cleaning effect.
• an isotonic solution for example a saline solution
• the lens reversibly again takes up water to revert to its original state.
• a pack for cleaning soft contact lenses comprises a volume of a solution containing Papain or Bromelain and a Lipolytic Enzyme, a device for forming droplets of the solutlon for depositing same on the surface of a soft contact lens and a volume of a sterile isotonic physiological saline solution in which the lens can be rinsed and subsequently boiled.
• a method of cleaning a soft contact lens in accordance with the invention to remove deposits on the surface of the lens by enzymatic action comprises the steps of placing at least one drop of a solution containing Papain or Eromelain and in addition a Lipolytic Enzyme, on the contact lens which is to be cleaned to reduce both Albumin and Lipids present to water soluble peptones, fatty acids and esters, and subsequently removing the resulting products by rinsing and boiling in a physiological saline solution.
• the enzyme activity in the cleaning solution is of the order of 100 tyrosine units per ug of protein.
• the fluid activity is allowed to occur for a period of the order of 15 minutes.
• the physiological saline solution has a particle size below 0.2 microns, and is isotonic, has a pH-value of 7.0 with a buffer capacity of 6-8 and is also sterile.
• a preferred enzyme solution for cleaning the lens consists of Bromelain, Mannitol, Sorbitol, Ethylenediaminetetraacetic acid, Sodium Metabisulphite, and a lipolytic enzyme.
• a preferred cleaning solution may consist of: diluted to 1 litre aqua dest., together with Lipase from cand. cylindracae, preferably in an amount corresponding to about 50000 units, in 1000 ml. 0.1 M Phosphate buffer in an aqueous polymer complex.
• An alternative cleaning solution (which comprises another aspect of the invention) which may be used to clean a soft contact lens consists of a solution of Lipase and a phosphate buffer.
• aqueous polymer complex which is conventional in the art and have for a purpose to bind the lipolytic enzymes so that it will not be unduly destroyed by the proteolytic enzyme.
• the nature of this polymer complex is not critical and any commercial product may be used, such as polyethylene glycol , polyvinyl alcohol, polyvinyl pyrrolidone and the like. As a fully non-limiting example one may mention the polymer complex "Kollodon'25 or 30 from BASF, West Germany.
• PMMA, HEMA and PvP all have a common factor, that is, they are lipid and protein retensive. New materials have been introduced such as silicone, even in this material there is lipid retention.
• the lipid deposits appear either as yellowish tinting of the lens or as a whitish haze.
• the deposits are composed of phospholipids, probably in the form of lecitin, forming together with the protein a lecitoprotein, (lecitin on exposure to heat and light tends to autocxidise or decompose into yellowish substances) or cholesterol and fat esters which are white in colour.
• plaque consists of a central core of lipid lying free on the polymer and protruding into the material matric causing a sand grain sensation when the lens lies in the eye.
• any lypolitie enzyme hydrolyzing the lipids to yield fatty acids and glycerol are useful.
• a preferred variety is lipase derived from cand. cylindracae, suitably prepared by lyophilization.
• a proteolytic enzyme any protein-digesting enzyme is useful, preferred examples being bromelain and papain.
• alipolytic enzyme and a proteolytic enzyme the latter being papain, it will be noted that the beneficial effect of free sulfhydryl groups on the activity of papain will be satisfied by the presence of the lipase containing sulfhydryl groups.
• such combination of enzymes is particularly preferred, especially when used in solutions of a hypertonic character.
• a preparation contact lens cleaning fluid (known as PROLEN) is made up as follows: Then add:-Lipase from cand. cylindracae 50000 units in 1000 ml. 0.1 M Phosphate buffer in an aqueous polymer complex.
• a second soft contact lens cleaning fluid (known as LIPREN) is made up as follows:-Lipase derived from cand. cylindracae, lyophilised 100 units. 0.1M phosphate buffer 10 ml.
• a few drops (0.3 ml) of the fluid are placed on a lens and left on the lens for 15 minutes. Tne lens is then rinsed in a saline solution and thereafter boiled in the saline solution for 20 minutes. Finally the lens is rinsed once more in the saline solution before reinserting.
• a lens is usually coated with deposits of protein, lipoproteins and lipids.
• the lens is treated with a preparation having a high enzymatic effect which contains a stabilised protease and a high activity lipase. Drops of the preparation are placed on the lens in accordance with the invention and it is left for the preparation to take effect, for 15 minutes.
• This cleaning preparation is, as described above, preferably formed from Bromelain, Mantitol, Sorbitol, Ethylenediaminetetraacetic acid, Sodium Metabisulphate and lipolytic enzyme.
• Complete removal of lipids from the lens is achieved by using a stabilised enzyme in fluid form and this may be applied either separately or as a second step. This is typically dripped onto the contact lens so as to remove any lipid deposits.
• the stabilised enzyme in fluid form is, as described above, preferably a lipase with a phosphate buffer.
• a further step in the clcaning operation involves rinsing the contact lens in a physiological saline solution and then boiling the lens in the same or a similar solution.
• the saline solution should be particle-free (i.e. have a particle size below 0.2 micron), should be isotonic, should have a pH-value of 7.0 and a buffer capacity of 6-8 and should also be sterile.
• the pH-value which is indicated is that value which will avoid smarting when the lens is subsequently inserted. An incorrect pH-value will cause smarting to occur. An incorrect pH-value will also cause the protein in the tear fluid to become denatured spontaneously which is not, of course, desirable.
• the solution is preferably packed in a disposable pack and is sterilised by means of Gamma radiation.
• the fluid consists of Lysozyme, Ig y-globulin, 1-lipoprotein, small amounts of carbohydrates and phospholipids.
• a similar solution was therefore prepared from the following:- ⁇ -chymotrypsin, serum albumin, lysozyme, bovine mucin, globulin II, ⁇ -blobulin III, globulin aid ⁇ -lipuproLein in 0.9 ⁇ NaCl solution.
• Lenses were placed in this prepared solution and left over night. Control lenses were kept in a sterile saline solution instead of the prepared solution. At the end of the period of storage the lenses were divided into four groups:-Group 1. The lenses in this first group were rinsed and then boiled in a sterile saline solution.
• the lenses in the second group were rinsed in a cleaning solution and then stored in a saline solution containing preservatives.
• the lenses in Group 3 were treated with an enzyme solution and subsequently rinsed and. boiled.
• the invention allows soft contact lenses to be cleaned rapidly and effectively and in general the cleaning operation should be carried out daily. However, where lenses are worn day and night, the interval between cleanings may be extended to every other or even every third day.
• the invention therefore provides for a simpler cleaning process than the known technique which requires the dissolving of tablets in water and also provides for a shorter cleaning period than hitherto. What is more important, however, is that the invention allows a more complete cleaning of the contact lens on account of the higher enzymatic activity. Unlike previously known cleaning preparations, the method according to the present invention is also designed to be used daily on the one hand for cleaning the lenses and on the other hand as a preventative measure to present the build-up of larger deposits of protein and lipids which after a time are difficult to remove and affect the properties of the lens.
• the types of enzymes which can be utilised may be Papain or Bromelain in each case together with a lipolytic enzyme. Cysteine and Polysaccharides may be used as substrate materials.
• Enzymatic activity should be of the order of 100 tyrosine units per ⁇ g of protein (substrate).
• the albumin By splitting the albumin into water-soluble peptones by enzymatic action, the latter can be rinsed or boiled away using a physiological saline isotonic solution.
• the invention pro.ides a stable liquid cleaning agent for cleaning sof contact lenses which can be stored under normal environmental conditions without loss of enzymatic activity thereby obviating the need to dissolve a tablet or quantity of powder in water so as to produce the clearing solution for the lens.
• quantity of the cleaning liquid need be used t: cover the surface of the lens and it is with this in mind that the invention provides for the application of the cleaning liquid by means of droplet applicator or the like.
• the PROLEN solution described above is used as a regular daily cleaning agent. This will remove most of the deposits normally found on the lens but will not completely remove the Lipid deposits.
• the steady build-up of Lipids is conveniently removed by periodically (e.g. monthly) cleaning the lens in LIPREN as described above.
• the Lipase in a phosphate buffer forming the LIPPEN effectively removes the Lipid build-up.

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• Chemical & Material Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Wood Science & Technology (AREA)
• Organic Chemistry (AREA)
• Detergent Compositions (AREA)
• Eyeglasses (AREA)

Applications Claiming Priority (4)

Publications (3)

Family

ID=26269028

Family Applications (2)

Family Applications After (1)

Country Status (7)

Cited By (9)

Families Citing this family (6)

Citations (4)

• 1979
  • 1979-04-20 WO PCT/SE1979/000097 patent/WO1979000963A1/fr unknown
  • 1979-04-20 JP JP50072079A patent/JPS55500262A/ja active Pending
  • 1979-04-20 FI FI791296A patent/FI791296A/fi not_active Application Discontinuation
  • 1979-04-20 CH CH1153779A patent/CH643663A5/de not_active IP Right Cessation
  • 1979-04-20 NO NO791335A patent/NO153107C/no unknown
  • 1979-04-23 EP EP79850032A patent/EP0005131B1/fr not_active Expired
  • 1979-04-23 DE DE7979850032T patent/DE2965421D1/de not_active Expired
  • 1979-11-19 EP EP79900454A patent/EP0015968A1/fr not_active Withdrawn

Patent Citations (5)

Non-Patent Citations (1)

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