JPS63165727A - Fluorescent agent for inspecting contact lens - Google Patents

Abstract

PURPOSE:To accurately inspect the fitting state or standard shape of a contact lens, by containing fluorecein isothiocyanate dextran in a fluorescent agent for inspecting the contact lens. CONSTITUTION:The fluorecein isothiocyanate dextran contained in a fluorescent agent for inspecting a contact lens acts as a fluorescent component by the irradiation of light such as black light. Since said fluorecein isothiocyanate dextran is obtained as the high MW fluorescent component, when the fluorescent component has high MW, the fluorescent agent for inspection is not infiltrated even in a hydrous contact lens, especially, a highly hydrous contact lens. Therefore, the observation of the fluorescent image present in the gap between the surface of an eyeball or a pole gauge and the contact lens becomes possible and the accurate fitting state or standard shape of the contact lens can be inspected.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fluorescent agent for contact lens inspection, which is used for inspecting the fitting condition of contact lenses or measuring the standard shape of contact lenses. The present invention relates to a fluorescent agent for contact lens inspection, which is suitably used for inspecting the finning state of hydrous contact lenses or measuring the standard shape of contact lenses.

The present invention can also be used to examine the anterior segment of the eye, for example, to examine the presence or absence of corneal stains.

[Conventional technology]

When prescribing contact lenses, it is necessary to choose the contact lenses of the most suitable standard for the eyes of contact lens wearers in order to provide them with good vision and to minimize discomfort such as the sensation of a foreign body. be.

In order to select the most suitable contact lens, a method is usually adopted in which the contact lens is actually worn and the finning condition of the contact lens is examined.

When inspecting the finning condition of contact lenses, fluorescein (molecular weight approximately 330
) is commonly used. That is, a contact lens is placed on the eyeball in advance, fluorescein is then instilled into the eye, and the fluorescein image present in the gap between the eyeball surface and the contact lens is observed to examine the finning state of the contact lens. .

However, testing of contact lenses using fluorescein is generally limited to testing hard contact lenses that do not exhibit water-containing properties, and is considered unsuitable for soft contact lenses that exhibit water-containing properties. This is because fluorescein is a component of a low-molecular-weight material, and therefore is easily impregnated into a hydrous contact lens. Then, not only the fluorescent image of the fluorescein present in the gap between the eyeball surface and the contact lens, but also the fluorescent image of the fluorescein impregnated into the lens is observed, making it difficult to determine the exact finning state of the contact lens. This is because it cannot be inspected.

In addition, when measuring the accurate standard shape of contact lenses, for hard contact lenses, the standard shape can be easily measured with a radius scope, etc., but for soft contact lenses, it is easy to measure the standard shape with a radius scope, etc. isn't it. Therefore, it is possible to use a ball gauge whose radius is defined at regular intervals to measure the finning condition in the same way as the above-mentioned inspection, but even if you try to implement this measurement method,
In the absence of suitable fluorescent agents such as fluorescein for hard contact lenses, measurement of standard shapes for soft contact lenses has been extremely difficult.

Therefore, contact lenses with relatively low water content, such as 2
- For contact lenses made of a copolymer mainly composed of hydroxyethyl methacrylate (water content: about 38%), attempts have been made to use fluorexone (also known as lucein), which has an average molecular weight of about 710. Because fluorexone has a larger molecular weight than fluorescein, it is hoped that this will prevent the fluorescent agent from entering the interior of water-containing contact lenses.

However, even with fluorescein, it is not possible to completely prevent the fluorescein from penetrating into the inside of a water-containing contact lens, and as a result, the lens may be dyed with the fluorescein, making it impractical for practical use. There wasn't enough to offer.

In addition, in recent years, highly water-containing contact lenses with a water content of 50% or more, such as contact lenses made of copolymers whose main components are N-vinylpyrrone, (meth)acrylamide derivatives, or vinyl alcohol, have become available. At present, there is a strong desire for a fluorescent agent for contact lens inspection, which has been developed and some of it is now on sale, and can be used for contact lenses that contain water, especially those with high water content.

Therefore, Japanese Patent Application Laid-Open No. 61-2787 proposes an invention relating to a fluorescent agent for contact lens inspection, which is made of an aqueous suspension of fine polymer particles to which a fluorescent substance is added.

However, since the fluorescent agent for contact lens inspection consists of an aqueous suspension of polymer fine particles to which a fluorescent substance has been added, it is difficult to synthesize the fine particles with uniform particle diameters. If large particles are present in the suspension, they may cause discomfort to contact lens wearers during examinations, such as a foreign body sensation, or they may be difficult to enter into the gap between the eyeball surface and the lens, making it difficult to obtain a good fluorescent image. However, there remained the problem that it became difficult to

[Problem that the invention seeks to solve]

Fluorescent agent for contact lens inspection is impregnated into the inside of the lens, not only for non-water-containing contact lenses such as hard contact lenses, but also for water-containing contact lenses, even high water-containing contact lenses. It is possible to observe the fluorescent image of the fluorescent agent present on the eyeball surface or in the gap between the ball gauge and the contact lens, making it possible to accurately inspect the fitting condition or standard shape of the contact lens. Fluorescent agents for contact lens inspection are strongly desired.

In addition, when a fluorescent agent uses fine particles as an ingredient, contact lens wearers may experience discomfort such as a foreign body sensation during examinations, or fine particles may enter the gap between the eyeball surface and the lens. It is desirable to have a fluorescent agent for contact lens inspection that does not cause problems such as difficulty in obtaining a good fluorescent image.

Of course, the fluorescent agent for contact lens inspection used must also be highly safe for living organisms.

[Means for solving problems]

As a result of extensive research, the present inventors have found that the present invention is extremely effective in overcoming the drawbacks of the prior art, and have completed the present invention.

That is, the present invention provides a fluorescent agent for contact lens inspection, which is characterized by containing fluorescein inthiocyanate dextran.

[Effect]

Fluorescein isothiocyanate dextran contained in the fluorescent agent for contact lens inspection of the present invention acts as a fluorescent component that emits fluorescent light when irradiated with light such as a black light. In addition, since fluorescein isothiocyanate dextran is obtained as a high-molecular-weight fluorescent component, if the fluorescent component has a high molecular weight, it can be used in water-containing contact lenses, even if the portion is a high-water-containing contact lens. The inside of the lens is never impregnated. Additionally, fluorescein isothiocyanate dextran is also water-soluble and can therefore be prepared as an aqueous solution.

[Structure of the invention]

Fluorescein isothiocyanate dextran is a fluorescent component in which fluorescein is bonded to dextran via an isothiocyanate. The fluorescein part is the part that emits fluorescence.

The molecular weight of fluorescein isothiocyanate dextran cannot be generalized because the applicable molecular weight is limited by the molecular gap of the contact lens material. Particularly in the case of water-containing contact lenses, the molecular gap tends to be controlled by the water content, so the range of molecular weight application of the fluorescent component is usually limited by the water content of the contact lens.

For example, when used for a low water content contact lens with a water content of about 40% or less, the average molecular weight of fluorescein isothiocyanate dextran is preferably about 1,000 or more. If the molecular weight is smaller than this range, there is a high possibility that fluorescein isothiocyanate dextran will be impregnated into a low water content contact lens. When used for highly water-containing contact lenses with a water content of approximately 80%, the average molecular weight of fluorescein isothiocyanate dextran is preferably about 100.000 or more.If the molecular weight is smaller than this range,
There is a high possibility that fluorescein isothiocyanate dextran will be impregnated into the lenses of highly water-containing contact lenses.

On the other hand, the molecular weight of fluorescein isothiocyanate dextran is too large (average molecular weight of about 1,
000.000 or more), the viscosity becomes high, making it difficult to handle, and elution from the eyes becomes difficult, which is not preferable.

Regarding the molecular weight of fluorescein isothiocyanate dextran, it is preferable to remove in advance those with a molecular weight that is too small or too large by a commonly used method such as dialysis.

Fluorescein isothiocyanate dextran is easily decomposed by heat, so do not sterilize it by heating.
It is desirable to perform sterile filtration using a membrane filter or the like.

The usage form of the present invention is usually to prepare an aqueous solution by dissolving fluorescein inthiocyanate dextran in physiological saline or the like and use it as a fluorescent agent for contact lens inspection, or to impregnate a filter paper with fluorescein inthiocyanate dextran. or use it.

When preparing an aqueous solution, the concentration of fluorescein isothiocyanate dextran varies depending on the concentration of effective fluorescent moiety (amount of bound fluorescein) per molecule of fluorescein isothiocyanate dextran, and cannot be generalized. In other words, if the effective concentration of the fluorescent moiety per molecule differs, the preferred concentration for use will naturally differ. For example, if you use fluorescein isothiocyanate dextran, which has a high effective concentration of fluorescent moieties per molecule, than if you use one with a lower gK of 70 degrees,
The concentration at which the fluorescein isothiocyanate dextran is prepared should be lower; on the other hand, if a fluorescein isothiocyanate dextran with a lower effective concentration of fluorescent moieties per molecule is used, one with a higher concentration can be used. It is better to prepare the fluorescein isothiocyanate dextran at a higher concentration than when using it.

For example, as a guide, 0.0 per mole of glucose residue
When using fluorescein isothiocyanate dextran, in which 0.7 moles of fluorescein are linked to dextran via isothiocyanate, the concentration is approximately 0.7 moles.
It is preferably 1 to 20 (W/V)%, more preferably about 1 to 10 (MV)%. In this case, if the concentration is lower than about 0.1 (W/V)%, there will be insufficient color development even when irradiated with light, making it impossible to clearly observe the shading of the fitting state. If it is higher than 20 (W/V)%, the coloring will be too strong and the shading of the fitting state will not be clearly observed, which is not preferable.

However, when preparing using fluorescein inthiocyanate dextran with a small molecular weight, a large amount of substances that do not have a fluorescent moiety may be mixed in, and the true effective concentration and calculated effective concentration may not necessarily match. Therefore, caution is required.

When impregnating filter paper, a portion of the filter paper in the form of a long and thin strip may be immersed in an appropriately (relatively high concentration) aqueous solution of fluorescein isothiocyanate dextran.

To inspect the fitting condition of contact lenses using the fluorescent agent for contact lens inspection of the present invention,
It can be performed in the same way as the conventional hard contact lens inspection method using fluorescein. That is, a contact lens is placed on the eyeball, the fluorescent agent for contact lens inspection of the present invention is instilled into the eye, and a fluorescent image of the fluorescent substance present in the gap between the eyeball surface and the lens is observed using a slint lamp or a black light. The fitting condition of contact lenses can be observed based on the shade of the color.

In order to instill a fluorescent agent for contact lens testing into the eye, if it is prepared as an aqueous solution, it is sufficient to instill 1 to 2 drops into the eye using a capillary or dropper; The tip of the filter paper impregnated with the fluorescent agent (preliminarily moistened with physiological saline if necessary) may be brought into contact with the lachrymal fluid of the eye, and the eye drops may be applied.

Furthermore, measuring the standard shape of a contact lens using a pole gauge can be done in the same way as inspecting the fitting condition of a contact lens. In other words, the measurement can be made by replacing the eyeball with a ball gauge.

The fluorescent agent for contact lens inspection of the present invention is suitably used for inspecting the finning state of water-containing contact lenses, particularly highly water-containing contact lenses with a water content of about 50% or more.

In addition, similar to hydrous contact lenses, it can also be suitably used for testing contact lenses made of composite materials, such as a non-hydroscopic hard material in the center and a hydrous soft material in the periphery. I can do it.

Of course, it can also be effectively applied to the inspection of the finning state of non-hydroscopic contact lenses, such as hard contact lenses or non-hydroscopic soft contact lenses.

In addition, instead of the conventionally used fluorescein, the inspection fluorescent agent of the present invention can also be used to inspect the anterior segment of the eye, for example, to inspect the presence or absence of corneal stains.

〔Example〕

EXAMPLES The present invention will be described in more detail below with reference to Examples, and its effects will be clarified, but the present invention is not limited to these Examples.

Example 1 0.5 g of fluorescein isothiocyanate dextran (manufactured by Sigma Chemical Co., Ltd.) having an average molecular weight of about 156□000, in which 0.007 mole of fluorescein is bound to dextran via isothiocyanate per mole of glucose residue, was added to 10 sjt of physiological saline. A fluorescent agent for contact lens inspection (concentration of fluorescein isothiocyanate dextran at 5 (W/V)%) was prepared by dissolving it in the solution.

In order to investigate whether the prepared fluorescent agent for contact lens inspection can be impregnated into a hydrous contact lens, the following experiment was conducted.

A highly water-containing contact lens with a water content of about 80% was immersed in the prepared fluorescent solution for contact lens inspection for about 1 hour, and then the contact lens was washed with distilled water. When the contact lenses were visually inspected to see if the fluorescent agent had been impregnated into the contact lenses, no trace of any residual fluorescent agent was observed.

Just to be sure, we examined the remaining fluorescent agent under blank light irradiation, and found that the edge of the lens was slightly colored, and it was confirmed that a small amount of fluorescent agent remained. When the fluorescent agent was immersed in water and boiled for 10 minutes, and the residual fluorescent agent was similarly observed by irradiation with a black light, the fluorescent agent seemed to have eluted, and no residual fluorescent agent was observed.

Comparative Example 1 A highly water-containing contact lens with a water content of about 80% was impregnated with a fluorescent component in the same manner as in Example 1 except that fluorescein isothiocyanate dextran having an average molecular weight of about 20,000 was used. When observing whether the fluorescent agent was impregnated into the contact lens, traces of residual fluorescent agent were confirmed. Furthermore, when the residual fluorescent agent was observed by irradiation with a black light, the entire lens developed a color, and this color development did not completely disappear even after 10 minutes of boiling treatment.

Comparative Example 2 A highly water-containing contact lens with a water content of about 80% was impregnated with a fluorescent component in the same manner as in Example 1 except that fluorescein isothiocyanate dextran having an average molecular weight of about 70,000 was used. When observing whether or not the fluorescent agent was impregnated into the contact lens, traces of residual fluorescent agent were confirmed as in Comparative Example 1. Furthermore, when the residual fluorescent agent was observed by irradiation with a black light, the entire lens developed a color, and this color development did not completely disappear even after 10 minutes of boiling treatment.

Example 2 An impregnation experiment with a fluorescent component was carried out in the same manner as in Example 1, except that a water-containing contact lens with a water content of about 38% and fluorescein inthiocyanate dextran with an average molecular weight of about 20,000 were used.

When observing whether the fluorescent agent was impregnated into the contact lens, no trace of residual fluorescent agent was confirmed. Furthermore, even when the residual fluorescent agent was observed by irradiation with blank light, no color developed at all.

Example 3 The following experiment was conducted to confirm whether or not fluorescein isothiocyanate dextran contained bacteria.

U.S.P.
When the number of viable bacteria in the fluorescent agent for contact lens inspection containing the same fluorescein isothiocyanate dextran used in Example 1 was examined using the membrane filter method in accordance with Pharmacopeia etc. were not confirmed.

Example 4 The following experiment was conducted to determine whether fluorescein isothiocyanate dextran is irritating or harmful to living organisms.

A fluorescent agent for testing was prepared by dissolving the same fluorescein isothiocyanate dextran used in Example 1 in physiological saline to a concentration of to(W/V)%. When the fluorescent agent was instilled into the eyes of domestic rabbits 15 times to examine irritation and damage to the ocular mucosa, the rabbits did not exhibit any abnormal behavior such as blinking or closing their mouth, and the eyelid mucosa and bulbar mucosa did not show any abnormal behavior. No hyperemia was observed, and no abnormal findings such as staining were observed on the cornea. As a result, there was no irritation or damage that could be attributed to fluorescein isothiocyanate dextran, and no significant difference was observed compared to the case of physiological saline.

Similarly, a fluorescein isothiocyanate dextran 10% (W/V) concentration of a fluorescent agent for contact lens testing was instilled into human eyes to examine irritation and damage to the ocular mucosa. During these examinations, the subject did not exhibit any abnormal behavior such as blinking or closing his/her mouth, there was no hyperemia in the eyelid mucosa or bulbar conjunctiva, and there were no abnormal findings such as stains on the cornea. As a result, there was no irritation or damage that could be attributed to fluorescein isothiocyanate dextran, and no significant difference was observed compared to the case of physiological saline.

This shows that fluorescein isothiocyanate dextran is quite safe for living organisms, especially for the eyes.

Example 5 The fitting condition of contact lenses was observed as follows.

A fluorescent agent for contact lens inspection was prepared by dissolving the same fluorescein isothiocyanate dextran used in Example 1 in physiological saline to a concentration of 5 (W/V)%. And the water content on the eyeball is 8
A 0% water-containing contact lens is worn, and then 1.2 drops of the above-mentioned fluorescent agent for contact lens inspection are instilled into the eye, and a fluorescent image of the fluorescent substance present in the gap between the eyeball surface and the lens is recorded using a blank light. The shading of the color was observed.

The shading of the fluorescent light was clear and the finning condition of the contact lens could be inspected well.

Example 6 Using the fluorescent agent for testing of the present invention, the anterior segment of the eye was tested as follows.

A fluorescent agent for testing was prepared by dissolving the same fluorescein isothiocyanate dextran used in Example 1 in physiological saline to a concentration of 5 (W/V)%. Then, 1.2 drops of a fluorescent agent was instilled into the eye, a fluorescent image of the fluorescent substance was colored using a black light, and the anterior segment of the eye was observed. Then, a fluorescent stain was observed on the cornea, which was confirmed to be a wound on the cornea.

〔Effect of the invention〕

The fluorescent agent for contact lens inspection of the present invention can also be obtained in which the fluorescein isothiocyanate dextran used as the fluorescent component has a high molecular weight. If a relatively high molecular weight fluorescent component is used, the fluorescent agent will not be impregnated into the inside of the lens, even if it is a water-containing contact lens or a highly water-containing contact lens. do not have.

In addition, since the fluorescent component is an aqueous solution, it may cause discomfort such as a foreign body sensation to contact lens wearers during examinations, which would occur if fine particles were used as a component, and fine particles may not come into contact with the ocular surface. There is no problem that it becomes difficult to get into the gap with the lens, making it difficult to obtain a good fluorescent image.

Furthermore, fluorescein inthiocyanate dextran used as a fluorescent component is also a safe component for living organisms.

Therefore, not only non-water-containing contact lenses such as hard contact lenses, but also water-containing contact lenses, even high water-containing contact lenses, can be used on the ocular surface or in the gap between the ball gauge and the contact lens. It becomes possible to observe the fluorescent image of the existing fluorescent agent,
It is possible to accurately inspect the finning state or standard shape of contact lenses.

In addition, similar to hydrous contact lenses, it can also be used to inspect contact lenses made of composite materials, for example, where the center portion is made of a non-hydroscopic hard material and the peripheral portion is made of a hydrous soft material.

When prescribing contact lenses, it is possible for the wearer to choose the contact lens of the most suitable standard for the eye, to achieve good visual acuity, and to eliminate foreign body sensations caused by mismatch between the cornea and the contact lens standard. This allows the wearer to experience as little discomfort as possible.

In addition, instead of the conventionally used fluorescein, the fluorescent agent for inspection of the present invention can also be used to inspect the anterior segment of the eye, for example, to inspect the presence or absence of corneal stains.

Claims (1)

[Claims] (1) A fluorescent agent for contact lens inspection, characterized by containing fluorescein isothiocyanate dextran.