A novel ion-exchange carrier based upon liposome-encapsulated montmorillonite for ophthalmic delivery of betaxolol hydrochloride

Abstract

As a novel ion-exchange carrier with high surface area and excellent exchangeability, montmorillonite (Mt) was intercalated with betaxolol hydrochloride (BH) to form a nanocomposite and then encapsulated by liposomes (Mt-BH-LPs) for an ophthalmic drug-delivery system. The Mt-BH and Mt-BH-LPs were prepared by an acidification process and ethanol injection combined with ammonium sulfate gradient methods. The successful formation of Mt-BH and Mt-BH-LPs was verified by thermogravimetric analysis, X-ray diffraction, Fourier-transform infrared spectra, and transmission electron microscopy. Mt-BH-LPs possessed the favorable physical characteristics of encapsulation efficiency, drug loading, mean particle size, and ζ-potential. In vitro release studies indicated Mt-BH-LPs effectively maintained a relatively sustained slow release. Immortalized human corneal epithelial cell cytotoxicity, in vivo rabbit eye-irritation tests, and chorioallantoic membrane–trypan blue staining all revealed that Mt-BH-LPs had no obvious irritation on ocular tissues. A new in vitro tear-turnover model, including inserts containing human corneal epithelial cells, was designed to evaluate the precorneal retention time of Mt-BH-LPs. The results showed that Mt-BH-LPs maintained a certain BH concentration in tear fluid for a longer period than the BH solution. In vivo precorneal retention studies also indicated Mt-BH-LPs prolonged drug retention on the ocular surface more than the BH solution. Furthermore, pharmacodynamic studies showed that Mt-BH-LPs had a prolonged effect on decreasing intraocular optical pressure in rabbits. Our results demonstrated that Mt-BH-LPs have potential as an ophthalmic delivery system.

Nano-Based Drug Delivery System: Recent Strategies for the Treatment of Ocular Disease and Future Perspective

“…The liposomal formulation consisted of Betaxolol Hydrochloride (BH) along with Montmorillonite (Mt) to form (Mt-BH-LP) in order to overcome poor ocular bioavailability. From this study, it was concluded that the developed and optimized Mt-BH-LP was effective in decreasing Intraocular Pressure (IOP) and maintaining higher ocular bioavailability [ 17 ].…”

New technologies of hypotensive drug delivery in glaucoma treatment

“…Многим исследователям представляется перспективным для доставки гипотензивных препаратов использовать комбинации полимеров и коллоидных систем: липосом [22][23][24][25][26], ниосом [27,28], кубосом [29], микроэмульсий [30], наноэмульсий [31][32][33] и наночастиц [34][35][36][37][38][39][40]. За счет медленного высвобождения лекарственных препаратов удается значительно пролонгировать время нахождения активного вещества в глазу.…”

Montmorillonite/chitosan nanoparticles as a novel controlled-release topical ophthalmic delivery system for the treatment of glaucoma

“…[22][23][24] In our previous study, BH molecules (as cationic compounds) could be successfully intercalated into the interlayer space to form a complex carrier (Mt-BH), which showed significant controlled release. 25,26 Based on this, we tried to develop a novel ion-exchange controlled-release delivery system to improve bioavailability and compliance of topical ophthalmic preparation for glaucoma treatment. In the present study, with the intercalation of BH into the interlayer space of the clay, the structure was further integrated with chitosan NPs.…”