Formulation of Silk Fibroin-based Single Polymeric Floating Microspheres for Sustained Release of Lafutidine

Purpose: The present study was aimed at the formulation of lafutidine-loaded silk fibroinbased floating microspheres (LAFU-SF-Microspheres) for the site-specific sustained release of the drug. Materials and Methods: Briefly, the single polymeric system comprising SF was selected to prepare LAFU-SF-Microspheres by employing the emulsion solvent evaporation method. Subsequently, the obtained LAFU-SF-Microspheres were assessed for particle size, zeta potential, percent entrapment efficiency (%EE), percentage drug content (%DC), micromeritics, floating profile, in-vitro drug release, spectroscopical analysis, and accelerated stability study. Results: The particle size and zeta potential of the LAFU-SF-Microsphere were found to be 2.3-6.8μm and -21.93mV respectively whilst % EE and % DC of LAFU-SF-Microspheres were found to be 86.83±3.46% and 93.89±3.98% respectively. Moreover, it demonstrated the adequate angle of repose (26.50±1.06°) and Carr’s Compressibility Index (CI) confirming the excellent flow properties. In view of the floating profile, LAFU-SF-Microspheres showed floating lag time (FLT) between 9-13sec and total floating time (TFT) more than 12hr. Moreover, the % buoyancy was found to be 97.62± 4.78%. LAFU-SF-Microspheres showed in-vitro % drug release up to 92.41±4.29% adopting the first-order model. The FTIR indicated successful incorporation of LAFU in LAFU-SF-Microspheres. The DSC and PXRD indicated the disrupted crystallinity of LAFU in LAFU-SF-Microspheres. The SEM images of microspheres displayed spherical shapes with smooth textures. Conclusion: SF microspheres can be fruitfully applied for customized floating and release patterns of drugs with distinct solubility classes.