Preparation and characterization of lung-targeting ceftiofur-loaded gelatin microspheres

Abstract

Background: Ceftiofur is an effective antibiotic against respiratory infections in livestock. However, ceftiofur concentration that is found in lungs after intravenous injection is not effective. Fortunately, ceftiofur-loaded gelatin microsphere (Cef-MS) enjoys advantages of lung-targeting and can achieve an effective concentration. However, no study has been reported on this modality of drug delivery.

Objective: We investigated the properties of this delivery modality—lung targeting ceftiofur-Cef-MSs.

Methods: We prepared Cef-MS and investigated drug loading, stability and release characteristics in vitro and studied tissue distribution patterns and potential lung injury in mice.

Results: Results showed that the average size and span value are 21.26 μm and 1.07, respectively. Drug loading and loading efficiency were 15.31 and 76.55%, respectively. Cef-MSs were stable in light, heat and humidity, except that agglutinative phenomenon was observed in 90% humidity after 10 days. Cef-MS presented a slower in vitro release pattern compared to ceftiofur. Cef-MS mainly concentrates in lungs after intravenous administration. Furthermore, histopathological studies showed that Cef-MS only induces mild and reversible lung injury and is biologically safe.

Conclusion: Cef-MS is a promising alternative form with high lung-targeting properties for the treatment of respiratory infections.

Keywords::

• Ceftiofur
• gelatin
• lung-targeting
• microsphere
• respiratory infections

Acknowledgment

The authors thank the cooperation of other faculty members in the Division of Pharmacology and Toxicology of the College of Veterinary Medicine at China Agriculture University.

Declaration of interest

The work was supported by the Qingdao’s Key Technologies Research and Development Program of China during the 11th Five-Year Plan Period (No. 2006-2-4-4-jch).