Desenvolvimento e caracterização de sistema polimérico para veiculação de sulfaguanidina com potencial atividade antiglaucomatosa.

Abstract

Glaucoma is the second leading cause of blindness worldwide, so early diagnosis and treatment enable better disease control. The treatment consists of drugs that reduce intraocular pressure using conventional pharmaceutical forms (eye drops). This approach decreases the efficiency in the treatment of the disease because its maintenance dosage leads to forgetfulness, systemic side effects and difficulty in application. In this sense, our research group has already developed extended-release systems (with 60 days) that still need improvements to maximize a longer release time. On the other hand, the molecules available therapeutically cause, in the long term, a decrease in efficiency. Thus, it is interesting to search for new molecules through their repositioning or to associate the therapies for treating this disease. Hence the development of new formulations, together with new drugs for the treatment of glaucoma, could reduce systemic adverse effects, increase adherence and insert a new molecule through its pharmacological repositioning. Therefore, this work aims to develop multilayer polymeric inserts to promote the controlled release of a potential active substance (sulfaguanidine). The inserts were produced by solubilization/solvent evaporation methods and characterized by differential exploratory calorimetry, infrared absorption spectroscopy, and scanning electron microscopy to verify possible compatibility between the polymer and the active substance, polymer hydration potential, surface pH, and in vitro release profile. The inserts showed high swelling capacity and physical resistance with approximately 1000% water influx. The pHs found (pH= 5) were compatible with the ocular application. All the inserts presented characteristic bands of the drug and the polymer in infrared spectroscopy without the appearance of new bands. Analogous results in thermogravimetry demonstrated compatibility between the drug and the polymer tested. The micrographs obtained by scanning electron microscopy observed regular and homogeneous surfaces and no drug was visualized inside the devices. The release test led to a rapid exit of the drug from the device in a test performed with cellulose membrane. The data presented made it possible to state that the inserts are compatible with sulfaguanidine, and new in vitro tests have to be done to certify the antiglaucomatous activity of this substance with this release system.