Improvement of the Biological Activity of a New Cobalt(III) Complex through Loading into a Nanocarrier, and the Characterization Thereof

摘要

In an effort to use a polymer carrier for the maintenance of biological activity of metal complexes; in this report, a novel cobalt(III) complex, trans-[Co(en)2(mtzt)2]NO3 (1) was prepared (en=ethylenediamine and Hmtzt=1-methyl-1-H-1,2,3,4-tetra- zol-5-thiol) and fully characterized. A biocompatible di-block polymer, containing poly lactic-co-glycolic acid and poly ethylene glycol (PLGA-PEG), was employed as the nanocarrier of complex 1 to achieve more efficacy and controlled drug release. Results illustrated that the successful loading of the cobalt complex on the PLGA-PEG polymer as well as pH dependent drug release with approximately 17%, 58% and 74% release within 168 hours at pH=7.4, 5.8 and 4.8 respectively. Antibacterial properties of complex 1 and corresponding nano- carrier have been determined against gram-negative (Escher- ichia coli) and gram-positive (Staphylococcus aureus) bacteria where the loading of the complex on nanocarrier enhances its antibacterial activity. Their anticancer activity was also eval- uated over human ovarian carcinoma cells and compared with cisplatin.