Evaluation of Daidzein-loaded Chitosan Microspheres <i>In Vivo</i> after Intramuscular Injection in Rats

Abstract

Daidzein-loaded chitosan microspheres were prepared by emulsiˆcation/chemical-crosslinking technique. The dialysis bag method determined the release of daidzein from the microspheres. It demonstrated that the accumulative release curve in vitro wasˆt for the zero-order release equation and had good correlation with the absorptive fraction in vivo, suggesting the dialysis bag method evaluated the release of the microspheres well. The release of chitosan determined by the ninhydrin assay in vitro was very slow, less than 3 percent at 35 day. The pathological section by hematoxylin-eosin staining found the good biocompatibility of the prepared microspheres in the injective site. Combining the degradation photos by scanning electron microscopy with the plasma concentration-time data, it was speculated that the drug on the surface of the microspheresˆrstly released, then the major of drug near the surface and the inner of the microspheres released by diŠusion through the shallow cavities and crack, lastly the drug released rapidly and completely being companied with the beginning of polymer degradation.

Hybrid Nanostructures Containing Sulfadiazine Modified Chitosan as Antimicrobial Drug Carriers

“…The release rate is controlled by the erosion/disruption of the CH nanofibers as was shown in other studies. Ge et al studied the release of various drugs from the chitosan matrix and the fate of chitosan in the release medium and found also a chitosan release from its microspheres immersed in PBS (pH = 7.4) which followed a slow (3% in 35 days) zero-order release mechanism [57]. Other authors demonstrated that the drug release depends on matrix degradation [52].…”