title: FRET acceptor suppressed single-particle photobleaching in semiconductor polymer dots.
abstract: Brightness and photostability are key parameters for fluorescent probes in optical imaging. This Letter describes Förster resonance energy transfer (FRET) as a useful strategy to enhance the photostability of fluorescent nanoparticles. Small molecules as FRET acceptors were doped into semiconductor polymer dots (Pdots), yielding apparent suppression of their rapid photobleaching in single-particle imaging. For 20 nm-diameter particles, the photobleaching percentage decreased from 71.8% to 47.2% after dye doping, while the single-particle brightness remained unchanged. The photostability of large Pdots was also enhanced by FRET at the expense of a moderate decrease in per-particle brightness as compared to the pure Pdots. This study indicates that FRET is a facile, yet effective, approach to mediate the brightness and photostability of fluorescent nanoparticles. Considering the combined factors of brightness and photostability, the dye-doped Pdots of ∼20  nm diameter are the most suitable for long-term imaging and tracking applications.
authors.forename: Zezhou
authors.initials: Z
authors.lastname: Sun
authors.forename: Siyang
authors.initials: S
authors.lastname: Liu
authors.forename: Zhihe
authors.initials: Z
authors.lastname: Liu
authors.forename: Weiping
authors.initials: W
authors.lastname: Qin
authors.forename: Danni
authors.initials: D
authors.lastname: Chen
authors.forename: Gaixia
authors.initials: G
authors.lastname: Xu
authors.forename: Changfeng
authors.initials: C
authors.lastname: Wu