Page 132 - Pharmaceutics IV (02-06-01305)

Ophthalmic DD: dosage forms

Liquid preparations

Mucoadhesive liquid preparations:
• Mucoadhesive polymers are commonly hydrophilic macromolecules

with a specific charge density.
• Examples are synthetic polymers (carbopol, polycarbophil and

cellulose derivatives) and natural polymers (chitosan and various
gums such as guar, xanthan and alginate).

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Ophthalmic DD: dosage forms

Liquid preparations

Emulsions
• Formulation concept:
➢ Mostly, they are o/w emulsions with submicron-sized globules

(microemulsion) prepared with well-tolerated oils (e.g., sesame
oil, castor oil, soya oil, …) and emulsifiers (e.g., phospholipids,
polysorbate 80, Cremophor RH, …).
➢ Each phase is typically sterilized before or during charging into the
mixing vessel.

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Salma E. EL-Habashy 129