Novel Swellable/Expandable Gastroretentive Floating Films of Gliclazide Folded in Capsule Shell for the Effective Management of Diabetes Mellitus: Formulation Development, Optimization and In vitro Evaluation
Background: Gliclazide (GLZ) belongs to the second-generation of sulphonylureas, is a drug of choice for the management of type II DM. It belongs to BCS Class II. The major site of drug absorption for GLZ is the stomach; it displayed variation in the drug absorption rate and bioavailability due to the shorter gastric retention time. Floating mechanism performance gets affected when the gastric fluid level not sufficiently higher, which ultimately obstructs the floating behavior, which is the major limitation of reported formulations. This limitation can get over by folded the film into the capsule shell that dissolved in gastric fluid and film swell/expands to dimensions higher than pylorus sphincter (12mm), thus prevents its evacuation. Objective: To explore the floating mechanism in the designing of films along with a tendency to expand by swelling and unfolding by utilizing a mixture of hydrophilic and hydrophobic polymer to achieve the controlled drug delivery and prolonged gastric retention of drug. Methods: The gastroretentive floating films were formulated by the solvent casting technique using 32 full factorial design and subjected to in vitro evaluation parameters, drug-excipient compatibility, X-ray diffraction and accelerated stability study. Results: The pre-formulation study established the purity and identification of drug. FTIR study confirmed no drug excipient interaction. F3, F6, and F9 were optimized based on in vitro floating characteristics, swelling/expanding ability, and unfolding time study. All developed formulations were unfolded within 14-22 min after capsule disintegration. The F3 was selected as final formulation as its ability to control the release of drug for 24 hrs followed by Zero-order kinetics having super case 2 transport. XRD confirmed the amorphousness of drug within formulation. The stability study results revealed that formulation was quite stable at extreme storage condition. Conclusion: The developed novel formulation has a good potential for the effective management and treatment of Diabetes Mellitus.