Development and in vitro-in vivo evaluation of containing usnic acid buccal formulations for use in oral ulcer treatment

Oral ulcers are characterized by the loss of the mucosal layer in the mouth. This loss can be acute or chronic, localized or common. Oral ulcer is one of the most common oral problems in primary care and may occur as a result of a number of diseases. As well as a variety of systemic disorders that may cause oral ulcers, problems in the oropharynx surrounding the formation of these lesions are also caused. Commercial formulations used in the topical treatment of ulcerative wounds stay short time in the mouth. Our study aims to present an effective, reliable formulation in which the formulations used in the treatment of oral ulcers remain in the application site for a longer period of time, and therefore the frequency of administration is reduced. Therefore, new drug delivery systems containing usnic acid were developed in the nanogel formulations using biocompatible, bioadhesive polymers. The analysis of the active substance was carried out and it was planned to start with calibration and validation studies. Nanogel formulations were prepared by different methods and the optimum formulations were selected their characterization such as zeta potential, polydispersity index and particle size. Usnic acid was loaded into the selected optimum formulations and characterization studies, physical properties, rheological properties, bioadhesive properties, in vitro release studies, ex vivo studies of the formulations were performed. The optimum usnic acid-loaded nanogel formulation were examined in vivo studies on the ulcerative wound in the mouth of the rabbits. Key words : Oral ulcer, nanogel, buccal formulations, usnic acid