The Effect of Hydration and Matrix Composition on Solute Diffusion in Rabbit Sclera

doi:10.1006/exer.2000.0909

Experimental Eye Research

Volume 71, Issue 5, November 2000, Pages 503-514

https://doi.org/10.1006/exer.2000.0909 Get rights and content

Abstract

There is increasing interest in the possibility for drug delivery into the vitreous humor across the conjunctiva and sclera as an alternative route to the conjunctiva–cornea pathway. As a preliminary to human studies we have investigated the influence of scleral composition and hydration on solute transport in the rabbit sclera. Intermuscular sclera was excised from adult New Zealand rabbits. Tissue samples were either examined directly (controls), digested using chondroitinase ABC or crosslinked using glutaraldehyde. The effect of these treatments on the ultrastructural appearance of the sclera was assessed. Diffusion and partition coefficients for solutes of different molecular weights [sodium chloride (23 MW),¹⁴C sucrose (342 MW) and dextran-fluoresceins (3, 10, 40 and 70 kDa)] were measured in relation to tissue treatment. The results were used to determine the effect of tissue structure and composition on solute movement. We have found that: (1) diffusion and partition coefficients are sensitive to solute MW, decreasing as MW increases; (2) diffusion and partition coefficients are sensitive to tissue hydration, increasing as hydration increases; (3) crosslinking of the sclera by glutaraldehyde reduced the partition coefficients significantly for solutes with MW over 3 kDa; and (4) removal of glycosaminoglycans has only a small effect on either diffusion or the partition coefficient.

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^f1: Address correspondence to: O.A. Boubriak.

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Regular ArticleThe Effect of Hydration and Matrix Composition on Solute Diffusion in Rabbit Sclera

Abstract

J. Pharm. Sci.

Biochim. Biophys. Acta

Mech. Ageing Dev.

Am. J. Ophthalmol.

Biochim. Biophys. Acta

Biochim. Biophys. Acta

Biophys. J.

Biochim. Biophys. Acta

Biochim. Biophys. Acta

Exp. Eye Res.

Biophys. J.

Vision Res.

Am. J. Ophthalmol.

Biophys. J.

J. Pharm. Sci.

Clin. Chim. Acta

Anal. Biochem.

Importance of the noncorneal absorption route in topical ophthalmic drug delivery

Invest. Ophthalmol. Vis. Sci.

Diffusion of high molecular weight compounds through sclera

Invest. Ophthalmol. Vis. Sci.

Transscleral delivery of bioactive protein to the choroid and retina

Invest. Ophthalmol. Vis. Sci.

The Extracellular Matrix

A molecular model of proteoglycan-associated electrostatic forces in cartilage mechanics

J. Biomech. Eng.

Characterization of diffusion across the sclera using FITC-conjugates of different molecular weights

Invest. Ophthalmol. Vis. Sci.

Glycoproteins of trabecular meshwork, cornea and sclera

Eye

Physiological function of connective tissue polysaccharides

Physiol. Rev.

Regular Article
The Effect of Hydration and Matrix Composition on Solute Diffusion in Rabbit Sclera