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SODIUM HYALURONATEA PRESENTATION BY SURYA PRAJAPAT
OPHTHALMIC SOLUTION
What is sodium hyaluronate?
1. It is a glycosaminoglycan present in the connective tissue.
2. It is a chain of disaccharide with a very high molecular weight.
3. Sodium hyaluronate is found naturally in the form of sodium salt, forming a highly viscous fluid with excellent wetting and lubricant properties.
SH is naturally present in the umbilical cord,
In the vitreous humor in the eye,
In synovial fluid, etc.
Present in the eye :
- tears
- lacrimal tissue
- corneal epithelium.
Properties of Sodium HyaluronateSodium hyaluronate has the following properties:
1. Visco-elastic Nature – Lubrication
2. Mucoadhesion
3. Mucomimesis
4. Water Retention
5. Wound Healing
6. Free radical scavenging.
7. Wetting Property
Visco-elastic Nature - Lubrication
Sodium Hyaluronate contains visco-elastic property.
Thus provide lubrication for a longer time.
What is Visco-elastic Behaviour?
Viscoelastic Property combines :
viscous properties of a liquid
+
elastic properties of a solid
depending on the shear stress applied.
How does it work in the eye???
BEFORE BLINKWhen the eye is open the SH molecules are not subject to a shear
stress, and form a randomly tangled
meshwork that creates a viscous, stable, long-lasting and protective coating on the surface
of the eye.
Between blinks SH forms a long-lasting protective coating
DURING BLINKDuring blinking, shear stress
causes the SH molecules in the solution to align in parallel with
one another. As a result, the solution becomes less viscous, more elastic and spreads easily
over the corneal surface. In addition, this reduction in
viscosity prevents the SH from being cleared from the eye,
providing better comfort than purely viscous fluids. While blinking, SH molecules align and spread easily over
the cornea
Therefore When used as an ocular lubricant, the unique viscoelastic properties of SH
increase the stability of the pre-corneal tear film and maximize tear film residence time.2, 3
Thus Provide Lubrication for Longer time.
2. Johnson ME et al. Graefe's Arch Clin Exp Ophthalmol 2006; 244: 109-12.
3. 3 Snibson GR et al. Eye 1990; 4: 594-602.
Adherence to the mucin layer (Muco-adhesivity)
SH molecules adhere well to the mucin layer of the precorneal tear film,
providing an effective and long-lasting coating of the
cornea.
# Saettone MF et al. Int J Pharm 1989; 51: 203-12.
Similar behaviour as the natural mucin layer (Mucomimesis)
It mimics the natural mucin layer of the tear film, which is done closely by SH in Fusion Fresh because,
SH possesses viscoelastic properties similar to those of the mucinlayer of the tear film.
Water retention
As a result of its coiled structure and large hydrophilic domains, SH attracts and retains a large amount of water,6 and therefore possesses
the ability to reduce water evaporation.7
Following instillation, SH solutions effectively moisturize the eye surface and prolongs the beneficial wetting effect over time.
6. Balazs EA, Band P.
Cosmetics Toiletries 1984;
99: 65-72.
7. Nakamura M et al.
Cornea 1993; 12: 433-6.
Healing of superficial keratitis
The biomechanical properties of SH prevent further damage to the cornea by creating a protective coating on the corneal
surface.
In addition, SH has been shown to have a beneficial effect in the healing of superficial keratitis by promoting rapid cell
migration.*
* Gomes JAP et al. Br J Ophthalmol 2004; 88: 821-25.
Free radical scavenging
SH molecules have been shown to have antioxidant properties* and therefore effectively protect the
ocular tissues against oxidative lesions caused by free radicals.
* Debbasch C et al. Invest Ophthalmol Vis Sci 2002; 43: 3409-15.
Wetting propertyThe main characteristic that distinguishes sodium hyaluronate from other wetting agents such as HPMC, carmelose, pvp, etc. is that its water-retention capacity is practically independent from ambient
humidity (moisture in surrounding).
This explains its property of maintaining constant wetting capacity even with significant changes in ambient humidity.
The result of this high level of wettability is that tear transparency remains stable, thereby increasing comfort.
Relief in Dry eye conditionsFusion Fresh eye drops provide soothing relief from the symptoms of
dry eyes, such as soreness, irritation or a gritty sensation.
These may be caused by your eye not producing enough tears to keep the eye moist, or by things such as certain medical conditions or treatments, prolonged use of computer screens (where you tend to blink less and thus not lubricate the eyes sufficiently), or drying atmospheric conditions such as air-conditioning, central heating or
atmospheric pollution.
Thank you.
A PRESENTATION BY SURYA PRAJAPAT
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