Zwitterionic Stealth Dye-Loaded Polymer Nanoparticles for Intracellular Imaging.

Fiche publication


Date publication

décembre 2019

Journal

ACS applied materials & interfaces

Auteurs

Membres identifiés du Cancéropôle Est :
Dr DUJARDIN Denis, Dr KLYMCHENKO Andrey


Tous les auteurs :
Runser A, Dujardin D, Ernst P, Klymchenko AS, Reisch A

Résumé

Intracellular applications of fluorescent nanoparticles (NPs) as probes and labels are currently limited by significant molecular crowding and the high level of complexity encountered inside living cells. The solution is to develop very small, bright, and noninteracting (stealth) NPs. Combining these properties requires implementing the stealth behavior through the thinnest possible hydrophilic shell. Here, we propose a one-step process for preparing ultrasmall and bright stealth NPs based on a zwitterionic (ZI) methacrylate-based copolymer. Dye-loaded polymer NPs are assembled through nanoprecipitation of the copolymer together with the salt of a rhodamine B derivative and a bulky hydrophobic counterion to achieve high particle brightness. We found that 10 mol % ZI groups in the polymer yield NPs of less than 15 nm that are stable in physiological salt conditions and practically resistant to protein adsorption, as suggested by fluorescence correlation spectroscopy. The combination of the very small size with the nonfouling nature of these particles enables spreading of ZI polymer NPs in the whole cytosol after their microinjection into living cells. In addition, single-particle tracking showed up to four times faster diffusion of ZI NPs in the cytosol compared to PEGylated NPs. The obtained dye-loaded ZI polymer NPs open the route to intracellular single-particle tracking and biosensing applications.

Mots clés

dye-loaded polymer nanoparticles, fluorescent nanoparticles, intracellular imaging, single-particle tracking, stealth nanoparticles, zwitterion coating

Référence

ACS Appl Mater Interfaces. 2019 Dec 24;: