Revolutionizing Levofloxacin Hemihydrate Delivery: Stomach-Specific Semi-IPN Microspheres with Carboxymethyl Cellulose and Pullulan for Optimal Performance

The current work focuses on developing a novel semi-interpenetrating polymer network (semi-IPN) microspheres of Levofloxacin hemihydrate (LH) composed of pullulan and carboxymethyl cellulose (CMC) via the emulsion crosslinking method. A Central Composite Design was used to optimize CMC, pullulan, and CaCl2 to maximize percent entrapment efficiency (EF) and achieve sustained drug release over twelve hours. Microspheres were characterized through FTIR, DSC, and SEM studies. H. pylori-infected rat model was used to perform the pharmacodynamic study, and gastro-retention was used to assess in vivo radiographic analysis. Compatibility between the drug and polymers was confirmed by DSC and FTIR analyses. The optimized formulation, containing 2.633% w/v CaCl2, 6.045% w/v pullulan, and 7.5% w/v CMC, demonstrated an entrapment efficiency of 59.31 ± 0.69% and released 96.78 ± 1.22% of the drug over 12 hours. X-ray showed microspheres in the stomach for up to 10 h. The LH microsphere formulation significantly reduced the bacterial colony count compared to LH powder, indicating superior efficacy. It can be indicated that the prolonged retention of microspheres in the gastric lining effectively targets the H. pylori reservoir, thereby enhancing the therapeutic efficacy of LH against H. pylori.