NANOTECHNOLOGYCAL TOOLS EMPLOYED TO IMPROVE THE OPHTHALMOLOGIC THERAPY.

DANIELA QUINTEROS

Mar del Plata

Congreso; VII REUNIÓN ANUAL DE LA SOCIEDAD ARGENTINA DE NANOMEDICINA (NANOMEDAR); 2016

Nanomedar -safe-sai-saic

Acetazolamide (AZM) is a carbonic anhydrase inhibitor,mainly used to reduce intraocular pressure in the treatmentor long-term management of glaucoma. However, the potential of topical treatment is limited, due to its low permeability in ocular epithelium. An alternative to overcome this limitation is the incorporation of AZM in nanopar ticulate systems, such as polymeric nanocapsules (NC).In this way, this work aimed to prepare, characterize in vitro and in vivo AZM-loaded NC using ethylcellulose (EC) and Eudragit® RS100 (EUD) as encapsulating polymers.These 􀀰Cs sho􀁙ed very high encapsulation efficiency,they were physically stable and their size was around 220-110 nm for NCEUD and NCEC, respectively. Due to the chemical characteristics of the polymers, NCEUD possesses positive surface charges, whereas for NCEC,the zeta potential was negative. In vitro release studiesshowed a characteristic release pattern corresponding to a classical behavior observed for devices based on a reservoir, where the properties of the polymer membrane modulate drug release. In both cases, the AZM release was practically independent regarding its concentration. Ex vivo assays, where the permeation through isolated cornea was studied, evidenced that the amount of AZMpermeated from EC and EUD nanoparticles was quite higher than in the case of AZM solution. We hypothesized that nanoparticles may work as a carrier facilitating drug penetration across the cornea. Besides, the very small size and the mucoadhesive properties of NCs, particularly NCEC, could favor a close contact with the cornea surface facilitating its penetration. In vivo studies, related to the hypotensive effect of NCs in normotensive rabbits, showed that 􀀰CEC formulation 􀁙as the most efficient, since an increased amount of permeated drug was observed, along with a greater IOP decrease and longer durationof the effect. This novel formulation could be a promising alternative for a more efficient treatment of glaucoma.