Preparation and characterization of novel multi-core chitosan microspheres for stomach-specific delivery of hydrophilic antibiotics.

Insufficient gastric mucosa drug concentration and short contact time were the main reason for the lack of eradication efficacy of Helicobacter pylori for peptic ulcer patients. Novel multi-core chitosan microspheres were prepared for stomach-specific delivery of hydrophilic antibiotics for the treatment of peptic ulcer. Chitosan microspheres with multiple Eudragit L100 cores were easily prepared by a new emulsification/coagulation encapsulating method. Swelling behaviors, surface amino groups and mucin absorption ability were investigated and the formulation that showed best mucoadhesive potential was adopted. The multi-core chitosan microspheres exhibited good mucoadhesiveness as well as controlled release manner for incorporated antibiotics in acidic environment. The release rate could be easily modulated with accumulative release ranging from 47.3 to 79.3% in 6 h. Accordingly, the multi-core chitosan microspheres could serve as a satisfactory vehicle for stomach-specific delivery of hydrophilic antibiotics.