Effect of shell thickness and composition on blinking suppression and the blinking mechanism in 'giant' CdSe/CdS nanocrystal quantum dots.
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.
Vela
Javier
J
Department of Chemistry, Iowa State University, Ames, Iowa 50011, USA.
Htoon
Han
H
Chen
Yongfen
Y
Park
Young-Shin
YS
Ghosh
Yagnaseni
Y
Goodwin
Peter M
PM
Werner
James H
JH
Wells
Nathan P
NP
Casson
Joanna L
JL
Hollingsworth
Jennifer A
JA
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
D019187:Cadmium Compounds; D005456:Fluorescent Dyes; D018036:Selenium Compounds; D013440:Sulfides; C034939:cadmium sulfide; C058667:cadmium selenide