| Abstract: | Polysaccharide coated PLA nanopartieles bearing aldehyde groups were prepared by dialysis of DMSO solution of cholesterol hydrophobic-modified dextran polyaldehyde and PLA against water.The average diameter of the nanoparticles was about 160 nm,and the size distribution was nearly homogenous.The nanoparticles were functionalized simultaneously with CD71 and EGFR antibody through the Schiff's base reaction,and then radiolabeled with 99mTc.After perfused the radiolabeled nanoparticles into tumor-bearing rats through left common carotid artery,the radioactivity in liver,spleen,kidney and brain was measured by scintillation counter.The results showed that less than 2% of nanoparticles were uptaken by the brain due to the uptake of the nanoparticles by the RES system.However,the coupling of transferrin antibody on the nanoparticles facilitated the penetration of nanoparticles across the blood brain barrier,and more specially,compared with monofuctionalized and native nanoparticles,the multifunctionalization enhanced the tumor accumulation of the nanoparticles in vivo. |
