A novel pH-sensitive magnetic alginate-chitosan beads for albendazole delivery.

Background: Drug delivery system using polymer-coated magnetic carriers is considered as an effective strategy for passive targeting, which can not only increase drug utilization but also reduce the adverse reaction. With the carriers, sensitivity to physical stimuli (e.g., magnetic field, pH) has been developed and drugs were conjugated to form incorporating magnetic particles, so that drugs could be located to desire position.

Method: Novel magnetic alginate (Alg)-chitosan (CS) beads loaded with albendazole (ABZ) were prepared and evaluated for pH sensitivity and drug release characteristics. The effects of six different factors (Alg concentration, the weight ratio of drug to polymer, the weight ratio of magnetite nanoparticles to polymer, CaCl2 concentration, CS concentration, the volume ratio of Alg to CS) were studied on the swelling ability of the magnetic beads. The magnetic beads were characterized by Fourier transform infrared spectroscopy, scanning electron microscope, and vibrating sample magnetometry. In addition, the delivery behavior of ABZ from the magnetic beads was studied.

Result: The magnetic Alg-CS beads had showed unique pH-dependent swelling behaviors and a continuous release of ABZ. From the magnetometer measurements data, the beads also had superparamagnetic property as well as fast magnetic response.

Conclusion: The pH-sensitive magnetic beads may be used as a magnetic drug targeting system for ABZ in the gastrointestinal tract.