الفهرس 
Anatomy of the eyeOnly 14 pages are availabe for public view
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Abstract
One can anticipate that, SLNs are well tolerated by ocular tissues because they are composed of physiological lipids, therefore, the in-vivo fate of this carrier occurs through metabolic pathways to a large extent. However, the toxicity of the emulsifiers has to be considered.
The unique characteristics and high sensitivity of the corneal and conjunctival tissues impose distinctive safety requirements and great restrictions on the selection of the components that can be used in the topical ocular preparations. A special consideration should be given to the ability of the inactive ingredients of the dosage form to affect the integrity of the epithelial layer, which causes irritation, burning, stinging, tearing or cytotoxic side effects to the eye.
Although non-ionic emulsifiers have proved to be relatively harmless to the eye compared to cationic and anionic emulsifiers, their safety to the ocular tissues upon chronic exposure should be assessed.
In-vitro cytotoxicity and viability determinations can be performed to assess the SLNs tolerability at cellular level. Many different, well defined ocular cell culture models are available for toxicity tests; in which parameter and conditions can be easily tailored according to the needs of the study.
Since, the work done in this thesis yielded stable, well tolerated in-vivo and pharmacologically active formulations for treatment of glaucoma; cooperation with industry for scaling up and commercialization of the proposed formulations is aspired to be implemented. Formulation of lipid based sustained release dosage forms have been widely promoted as a way of achieving site specific drug delivery with increased bioavailability; not only by prolonged residence time on the ocular surface due to their nanosize, but also by slowing down the drug elimination. Many challenges are facing the development of an effective ophthalmic dosage form. The rapid turnover of the lachrymal fluids and the efficient drainage apparatus make ophthalmic solutions rapidly eliminated. The two major issues that determine ocular drug bioavailability; are duration of residence on the ocular surface and corneal permeability. Lipid based nanocarriers can enhance ocular drug bioavailability by addressing both of these issues.
Brimonidine tartrate, a highly selective α2 agonist for glaucoma treatment; was chosen as the model drug in this thesis to prepare lipid nanoparticulate ocular dosage forms.