title: Aggregation control of quantum dots through ion-mediated hydrogen bonding shielding.
abstract: Nanoparticle stabilization against detrimental aggregation is a critical parameter that needs to be well controlled. Herein, we present a facile and rapid ion-mediated dispersing technique that leads to hydrophilic aggregate-free quantum dots (QDs). Because of the shielding of the hydrogen bonds between cysteamine-capped QDs, the presence of F(-) ions disassembled the aggregates of QDs and afforded their high colloidal stability. The F(-) ions also greatly eliminated the nonspecific adsorption of the QDs on glass slides and cells. Unlike the conventional colloidal stabilized method that requires the use of any organic ligand and/or polymer for the passivation of the nanoparticle surface, the proposed approach adopts the small size and large diffusion coefficient of inorganic ions as dispersant, which offers the disaggregation a fast reaction dynamics and negligible influence on their intrinsic surface functional properties. Therefore, the ion-mediated dispersing strategy showed great potential in chemosensing and biomedical applications.
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, Hunan University, Changsha 410082, PR China.
authors.forename: Jianbo
authors.initials: J
authors.lastname: Liu
authors.forename: Xiaohai
authors.initials: X
authors.lastname: Yang
authors.forename: Kemin
authors.initials: K
authors.lastname: Wang
authors.forename: Xiaoxiao
authors.initials: X
authors.lastname: He
authors.forename: Qing
authors.initials: Q
authors.lastname: Wang
authors.forename: Jin
authors.initials: J
authors.lastname: Huang
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
mesh_terms: D003102:Colloids / Q000737:chemistry*; D003460:Crystallization / Q000379:methods; D006860:Hydrogen Bonding; D007477:Ions; D008422:Materials Testing; D036103:Nanotechnology / Q000379:methods*; D045663:Quantum Dots; D014025:Titanium / Q000737:chemistry*
chemical_list: D003102:Colloids; D007477:Ions; C009495:titanium dioxide; D014025:Titanium