Development and in vitro Characterization of Gastroretentive Formulations as Calcium Pectinate Hydrogel Pellets of Pregabalin by Ionotropic Gelation Method

Introduction: Pregabalin (PG) is primarily prescribed for epilepsy, painful diabetic neuropathy, post-herpetic neuralgia, and fibromyalgia. Also, it is used in clinical practice to treat general anxiety disorder due to its anxiolytic properties. Pectin is a watersoluble ionic polysaccharide. As a result of the interaction of pectin with calcium ions, a hydrophilically coated insoluble carrier system is formed by complexing between surfaces, which provides a sustained release. In this direction, floating hydrogel pellets containing PG were developed and characterized in our study. This study aimed to make a sustained release of PG, reach the optimum level in characterization, and bring a new approach to widely used oral drug therapy. Materials and Methods: PG was a gift from Ilko Pharmaceuticals (Turkey) and pectin was purchased from CPKelco (USA). The ionotropic gelation technique was used to prepare pellets. To characterize the pellets, flotation/swelling degrees, yield, drug loading capacity/encapsulation efficiency, particle size/distribution, in-vitro release/kinetics, and morphological studies have been done. Also, the structural features of pellets have determined via the Fourier Transform Infrared (FT-IR), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), and X-ray diffraction (XRD) studies. Results: The formulations have been successfully developed without using any coating agent to prolong drug release for 24 h with an encapsulation efficiency of ~82%. Optimum results were obtained in characterization studies. As a result of BET analysis, it has been proven that the structure is porous and there is no change in the chemical and crystal structure of PG by FT-IR and XRD studies. Conclusion: We anticipate that the formulation we developed will provide an alternative to the sustained-release PG preparations in the current pharmaceutical market.