Single-step synthesis of N-doped carbon dots and applied for dopamine sensing, in vitro multicolor cellular imaging as well as fluorescent ink

Abstract

A water-soluble, simple, and facile nitrogen-doped carbon dots (N-CDs) were developed by a single-step via the pyrolysis process and utilized in the fluorometric detection of dopamine (DA). DA is a neurotransmitter and plays a vital role in regulating several biological activities in mammalians. DA can oxidize into DA-quinone by the addition of N-CDs. The emission intensity of N-CDs can be quenched by DA through the inner filter effect (IFE) procedure. This detection mechanism is characterized by UV–vis spectroscopy and fluorescence lifetime decay study. The synthesized N-CDs are highly selective and sensitive towards DA, and their detection limit is 0.2 nM with a linear range of 0.001−1 μM. More importantly, N-CDs are utilizing to detect DA in the human blood serum. The as-synthesized N-CDs have excellent optical properties and are potentially used as a staining material for multicolor cellular imaging of MDA-MB 468 human breast cancer cells. Moreover, N-CDs are also used as a fluorescent ink and can be used for information storage. Hence, the as-synthesized N-CDs are explored as fluorescence materials for DA sensing, multicolor cellular imaging, and fluorescent ink.