Single-particle fluorescence intensity fluctuations of carbon nanodots

Nano Lett. 2014 Feb 12;14(2):620-5. doi: 10.1021/nl403820m. Epub 2014 Jan 10.

Abstract

Fluorescent carbon nanodots (CNDs) were synthesized in oxidized and reduced forms and were analyzed at the single-particle level. Images of single CNDs at different excitation energies revealed significant heterogeneity in the lower energy trap sites between particles. We observed that a high percentage of reduced CND particles transitioned between multiple fluorescence intensity levels indicative of multichromophoric systems. Despite this behavior, individual CNDs exhibit single-step photobleaching and transient blinking to the background level suggesting single-molecule behavior.