Piplani P, Kumar P, Rohilla A,
Topical beta-blocking agents are nowadays the drugs of choice as these have few ocular and systemic side effects. In the present study some selected beta blockers (PP-24, PP-34, PP-41, PP-48, PP-50), synthesized using 4-hydroxybenzaldehyde and isovanillin were encapsulated into niosomes possessing a high drug entrapment efficiency in order to be used as ophthalmic carriers for topical ocular treatment. Prepared niosomes were characterized for morphology, number of vesicles per cubic millimeter, entrapment efficiency and drug content. Incorporation of the drug into respective niosomal preparation was confirmed by DSC. TEM studies showed that vesicles were small in size, round in shape, bilamellar/unilamelar without any aggregation. No significant variation in particle size and drug content of prepared niosomes was observed, upon storage, over a period of 42 days at 4-8°C. Ex vivo permeability studies indicated that PP-24 formulation showed the maximum enhancement in corneal permeability (27.29%) as compared to the free drug (11.33%). Onset of action of all the developed formulations was 0.5 h which was comparable to timolol. Formulation PP-24 produced sustainable and better IOP lowering effect than formlation PP-34. This may be attributed to lower particle size and better entrapment efficiency of the PP-24 niosomal formulation.