Gated and near-surface diffusion of charged fullerenes in nanochannels.
Nanoparticles and their derivatives have engendered significant recent interest. Despite considerable advances in nanofluidic physics, control over nanoparticle diffusive transport, requisite for a host of innovative applications, has yet to be demonstrated. In this study, we performed diffusion experiments for negatively and positively charged fullerene derivatives (dendritic fullerene-1, DF-1, and amino fullerene, AC60) in 5.7 and 13 nm silicon nanochannels in solutions with different ionic strengths. With DF-1, we demonstrated a gated diffusion whereby precise and reproducible control of the dynamics of the release profile was achieved by tuning the gradient of the ionic strength within the nanochannels. With AC60, we observed a near-surface diffusive transport that produced release rates that were independent of the size of the nanochannels within the range of our experiments. Finally, through theoretical analysis we were able to elucidate the relative importance of physical nanoconfinement, electrostatic interactions, and ionic strength heterogeneity with respect to these gated and near-surface diffusive transport phenomena. These results are significant for multiple applications, including the controlled administration of targeted nanovectors for therapeutics.
Department of Nanomedicine, Methodist Hospital Research Institute, 6670 Bertner Street, M.S. R2-216, Houston, Texas 77030, United States.
Alessandro
A
Grattoni
Daniel
D
Fine
Erika
E
Zabre
Arturas
A
Ziemys
Jaskaran
J
Gill
Yuri
Y
Mackeyev
Matthew A
MA
Cheney
Delia C
DC
Danila
Sharath
S
Hosali
Lon J
LJ
Wilson
Fazle
F
Hussain
Mauro
M
Ferrari
D003198:Computer Simulation; D037741:Fullerenes / Q000737:chemistry*; D008422:Materials Testing; D008956:Models, Chemical; D008958:Models, Molecular; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D016062:Porosity; D055672:Static Electricity
D037741:Fullerenes