Shizhen Chen
Chinese Academy of Sciences, China
Title: pH-Responsive theranostic nanocomposites as synergistically enhancing positive and negative magnetic resonance imaging contrast agents
Biography
Biography: Shizhen Chen
Abstract
The rational design of theranostic nanocomposite exhibiting synergistic turn-on of therapeutic potency and enhanced diagnostic imaging in response to tumor milieu is critical for efficient personalized cancer therapy.We here in fabricate a theranostic nanocomposites Mn-porphyrin & Fe3O4@SiO2@PAA-cRGD, which could synergistically enhancing positive and negative magnetic resonance imaging signals for both accurate tumor imaging and pH-responsive drug release. Fluorescent imaging also showed that the nanocomposite specifically accumulated in lung cancer cells by a receptor-mediated process, and were nontoxic to normal cells. The r2/r1 ratio varied is 20.6 in neutral pH 7.4 , r2/r1 ratio 7.7 in acidic pH 5.0, which suggesting the NCs could act as an ideal T1/T2 dual-mode contrast agents at acidic environments of tumor areas. For in vivo MRI, T1 and T2 relaxation was significantly accelerated to 55% and 37%, respectively, in the tumor after i.v. injection of nanocomposites. The results demonstrate great potential of such nanocomposites for real-time imaging with greatly enhanced diagnostic accuracy during targeted therapy.
