Preparation and characterization of alginate/chitosan formulations for ciprofloxacin-controlled delivery.

In this work, alginate beads loaded with ciprofloxacin (AL_CP) and alginate beads loaded with ciprofloxacin and covered by chitosan (AL_CP_CS) were prepared by emulsification technique in combination with internal gelation method. Physicochemical characterization of the resulting formulations revealed the hydrodynamic diameter and Zeta potential ca. 160 nm and ca. -32 mV in the case of AL_CP and ca. 240 nm and ca. +14 mV in the case of AL_CP_CS (pH = 6.0), respectively. Kinetics of ciprofloxacin release from alginate/chitosan formulations was studied in different media (pH = 1.2, 6.8, and 7.4). Covering alginate core with a polycation such as chitosan moderates the drug release, resulting in a pH-sensitive hybrid controlled-release system. Herein, alginate beads with encapsulated ciprofloxacin covered with chitosan are proposed as an effective oral delivery system since the drug release from alginate core is limited in low pH solution (gastric conditions).