A biodegradable tumor targeting nano-probe based on poly(ε-caprolactone)-b-poly(ethylene glycol) block copolymer (PCL-b-PEG)micelle functionalized with a magnetic resonance imaging (MRI) contrast agent diethy...A biodegradable tumor targeting nano-probe based on poly(ε-caprolactone)-b-poly(ethylene glycol) block copolymer (PCL-b-PEG)micelle functionalized with a magnetic resonance imaging (MRI) contrast agent diethylenetriaminepentaacetic acid-gadolinium (DTPA-Gd+) on the shell and a near-infrared (NIR) dye in the core for magnetic resonance and optical dual-modality imaging was prepared. The longitudinal relaxivity (rl) of the PCL-b-PEG- DTPA-Gd3+ micelle was 13.4 (mmol/L)^-1s^-1, three folds of that of DTPA-Gd3+, and higher than that of many polymeric contrast agents with similar structures. The in vivo optical imaging of a nude mouse bearing xenografied breast tumor showed that the dual-modality micelle preferentially accumulated in the tumor via the folic acid-mediated active targeting and the passive accumulation by the enhanced permeability and retention (EPR) effect. The results indicated that the dualmodality micelle is a promising nano-probe for cancer detection and diagnosis.展开更多
基金supported by the National Natural Science Foundation of China(No.20904046)the National Basic Research Program(973 Program)(No.2009CB526403) of China+1 种基金the Doctoral Fund of Ministry of Education of China(No.20090101120159)the Qianjiang Talent Program of Zhejiang Province,China(No.2010R10050)
文摘A biodegradable tumor targeting nano-probe based on poly(ε-caprolactone)-b-poly(ethylene glycol) block copolymer (PCL-b-PEG)micelle functionalized with a magnetic resonance imaging (MRI) contrast agent diethylenetriaminepentaacetic acid-gadolinium (DTPA-Gd+) on the shell and a near-infrared (NIR) dye in the core for magnetic resonance and optical dual-modality imaging was prepared. The longitudinal relaxivity (rl) of the PCL-b-PEG- DTPA-Gd3+ micelle was 13.4 (mmol/L)^-1s^-1, three folds of that of DTPA-Gd3+, and higher than that of many polymeric contrast agents with similar structures. The in vivo optical imaging of a nude mouse bearing xenografied breast tumor showed that the dual-modality micelle preferentially accumulated in the tumor via the folic acid-mediated active targeting and the passive accumulation by the enhanced permeability and retention (EPR) effect. The results indicated that the dualmodality micelle is a promising nano-probe for cancer detection and diagnosis.