title: Effect of shell thickness and composition on blinking suppression and the blinking mechanism in 'giant' CdSe/CdS nanocrystal quantum dots.
abstract: We recently developed an inorganic shell approach for suppressing blinking in nanocrystal quantum dots (NQDs) that has the potential to dramatically improve the utility of these fluorophores for single-NQD tracking of individual molecules in cell biology. Here, we consider in detail the effect of shell thickness and composition on blinking suppression, focusing on the CdSe/CdS core/shell system. We also discuss the blinking mechanism as understood through profoundly altered blinking statistics. We clarify the dependence of blinking behavior and photostability on shell thickness, as well as on interrogation times. We show that, while the thickest-shell systems afford the greatest advantages in terms of enhanced optical properties, thinner-shell NQDs may be adequate for certain applications requiring relatively shorter interrogation times. Shell thickness also determines the sensitivity of the NQD optical properties to aqueous-phase transfer, a critical step in rendering NQDs compatible with bioimaging applications. Lastly, we provide a proof-of-concept demonstration of the utility of these unique NQDs for fluorescent particle tracking.
authors.affiliation: Department of Chemistry, Iowa State University, Ames, Iowa 50011, USA.
authors.forename: Javier
authors.initials: J
authors.lastname: Vela
authors.forename: Han
authors.initials: H
authors.lastname: Htoon
authors.forename: Yongfen
authors.initials: Y
authors.lastname: Chen
authors.forename: Young-Shin
authors.initials: YS
authors.lastname: Park
authors.forename: Yagnaseni
authors.initials: Y
authors.lastname: Ghosh
authors.forename: Peter M
authors.initials: PM
authors.lastname: Goodwin
authors.forename: James H
authors.initials: JH
authors.lastname: Werner
authors.forename: Nathan P
authors.initials: NP
authors.lastname: Wells
authors.forename: Joanna L
authors.initials: JL
authors.lastname: Casson
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Hollingsworth
mesh_terms: D019187:Cadmium Compounds / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000737:chemistry; D008163:Luminescent Measurements; D055620:Optical Phenomena; D045663:Quantum Dots; D018036:Selenium Compounds / Q000737:chemistry*; D013440:Sulfides / Q000737:chemistry*; D013997:Time Factors
chemical_list: D019187:Cadmium Compounds; D005456:Fluorescent Dyes; D018036:Selenium Compounds; D013440:Sulfides; C034939:cadmium sulfide; C058667:cadmium selenide