Luminescent Carbon Dot Mimics Assembled on DNA

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Biotechnology

Background:

• Carbon dots are widely studied for bioimaging but suffer from inhomogeneity and limited emission wavelengths.
• Existing carbon nanomaterials often lack tunable emission and can be difficult to synthesize homogeneously.

Purpose of the Study:

• To develop homogeneous, soluble, and photostable carbon-based nanomaterials with tunable emission properties for bioimaging.
• To address the limitations of traditional carbon dots by utilizing a DNA scaffold for precise molecular assembly.

Main Methods:

• Synthesized five different aromatic hydrocarbon deoxyribosides.
• Assembled these monomers into 1296 unique tetramer compounds on PEG-polystyrene beads using a DNA scaffold.
• Screened assemblies for photostability and visible light emission (400-680 nm) using 365 nm excitation.

Main Results:

• Identified six DNA-carbon assemblies (DNA-CAs) with exceptional photostability and emission across the visible spectrum (400-680 nm).
• Observed high Stokes shifts (up to 110 nm), quantum yields (0.01-0.29), and fluorescence lifetimes (3-42 ns).
• Demonstrated white light emission from several DNA-CAs in aqueous solution and successful application in multispectral cell imaging.

Conclusions:

• DNA-carbon assemblies offer a versatile platform for creating homogeneous, rapidly synthesized carbon chromophores with tunable optical properties.
• These novel materials overcome limitations of carbon dots, expanding possibilities for multicolor and white light bioimaging in aqueous environments.
• The DNA scaffold enables precise control over carbon assembly, leading to advanced molecular compounds for biotechnological applications.