title: Rapid cytosolic delivery of luminescent nanocrystals in live cells with endosome-disrupting polymer colloids.
abstract: Luminescent nanocrystals hold great potential for bioimaging because of their exceptional optical properties, but their use in live cells has been limited. When nanocrystals enter live cells, they are taken up in vesicles. This vesicular sequestration is persistent and precludes nanocrystals from reaching intracellular targets. Here, we describe a unique, cationic core-shell polymer colloid that translocates nanocrystals to the cytosol by disrupting endosomal membranes via a low-pH triggered mechanism. Confocal fluorescence microscopy and flow cytometry indicate that picomolar concentrations of quantum dots are sufficient for cytosolic labeling, with the process occurring within a few hours of incubation. We anticipate a host of advanced applications arising from efficient cytosolic delivery of nanocrystal imaging probes: from single particle tracking experiments to monitoring protein-protein interactions in live cells for extended periods.
authors.affiliation: The Molecular Foundry, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA.
authors.forename: Andrea R
authors.initials: AR
authors.lastname: Bayles
authors.forename: Harvind S
authors.initials: HS
authors.lastname: Chahal
authors.forename: Dev S
authors.initials: DS
authors.lastname: Chahal
authors.forename: Cheryl P
authors.initials: CP
authors.lastname: Goldbeck
authors.forename: Bruce E
authors.initials: BE
authors.lastname: Cohen
authors.forename: Brett A
authors.initials: BA
authors.lastname: Helms
mesh_terms: D002470:Cell Survival; D003102:Colloids / Q000737:chemistry* / Q000378:metabolism; D011992:Endosomes / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D006863:Hydrogen-Ion Concentration; D049449:Luminescence; D018613:Microscopy, Confocal / Q000379:methods; D053758:Nanoparticles / Q000737:chemistry; D011108:Polymers / Q000737:chemistry* / Q000378:metabolism; D045663:Quantum Dots
chemical_list: D003102:Colloids; D011108:Polymers