AN ATTEMPT TO UNDERSTAND AND VALIDATE THE FACTORS CONTROLLING IN-SITU RAFT FORMATION PROCESS

In this study, in-situ raft forming Levofloxacin Suspension formulation was developed. In-vitro conditions like temperature, pH, and RPM simulating the in-vivo conditions like gastric pH, body temperature, and gastric motility respectively were identified as critical process parameters in system scale-up studies. Challenging and characterization were performed in-vitro. The working limits were identified and verified by calculation of process capability indices. Process Potential (Cp) and Process performance (Cpk)  values greater than 2, and 1.33 respectively helped to select the conditions for the formation of raft system controlling the release up to 8 h with zero order release kinetics found to be significant (R²=0.9930). The release mechanism was found to be Korsemeyer-peppas showing the mechanism of drug release by diffusion and relaxation of polymeric raft structure. The Suspension formulation subjected to stability studies (40 ºC ± 2 ºC / 75% ± 5% RH) were found to be stable for pH, viscosity, floating lag time, content uniformity and percentage drug release from the raft structure. Moreover, radiographic x-rays evaluation for optimized formulation for the validation of set in-vitro protocol revealed that the raft structure formed in-vivo elicits excellent gastric retention as proposed in observations and removed from the body within safe period of 24 h.