Counterion-insulated near-infrared dyes in biodegradable polymer nanoparticles for <i>in vivo</i> imaging
Joanna Sobska, Bohdan Andreiuk, Ilya O. Aparin, Andreas Reisch, Wojciech Krężel, Andrey S. Klymchenko
Abstract
imaging of wild-type mice with a good contrast after IV injection. Compared to the bare PLGA NPs, PLGA-PEG NPs exhibited significantly slower accumulation in the liver. Biodistribution studies confirmed the preferential accumulation in the liver, although PLGA and PLGA-PEG NPs could also be distributed in other organs, with the following tendency: liver > spleen > lungs > kidney > heart > testis > brain. Overall, the present work validated the counterion approach for encapsulation of NIR cyanine dyes into biodegradable polymer NPs bearing covalently attached PEG shell. Thus, we propose a simple and robust methodology for preparation of NIR fluorescent biodegradable polymer NPs, which could further improve the existing optical imaging for biomedical applications.