Fluorescence correlation spectroscopy of CdSe/ZnS quantum dot optical bioimaging probes with ultra-thin biocompatible coatings.
The current study reports on the colloidal stabilities and emission properties of CdSe/ZnS quantum dot (QD) optical probes capped with a variety of thin, hydrophilic surface coatings as studied using confocal fluorescence correlation spectroscopy. These coatings are based on mercaptoethanol, mercaptopropionic acid (with and without conjugated aminoethoxyethanol), lipopolymers (DSPE-PEG2000), cysteine (Cys), and a variety of Xaa-Cys dipeptides. The study shows that several types of QDs with thin hydrophilic coatings can be designed that combine good colloidal stability and excellent emission properties (brightness). Furthermore, there is a general correlation between colloidal stability and brightness. The experiments reported herein illustrate that QDs with multiple types of thin coatings can be created for optical imaging applications in a biological environment while also maintaining a size below 10 nm.
Murcia
Michael J
MJ
Department of Chemistry & Chemical Biology, Purdue School of Science, Indiana University-Purdue University Indianapolis (IUPUI), 402 North Blackford Street, Indianapolis, IN 46202, USA.
Shaw
David L
DL
Long
Eric C
EC
Naumann
Christoph A
CA