Surface Copassivation Strategy for Developing Water-Soluble InP Colloidal Quantum Dots with High Luminescence and...

Area of Science:

• Nanotechnology
• Materials Science
• Biotechnology

Background:

• Colloidal quantum dots (QDs) are excellent fluorescent emitters for biological applications.
• Cadmium-based QDs pose toxicity risks and have poor aqueous-phase performance.
• Existing water-soluble indium phosphide (InP) QDs lack effective surface protection, limiting their optical properties.

Purpose of the Study:

• To develop water-soluble InP-based QDs with enhanced optical properties for biological applications.
• To overcome the limitations of cadmium-based QDs and improve InP QD performance in aqueous environments.
• To create environmentally friendly fluorescence labels for cellular imaging.

Main Methods:

• An efficient copassivation strategy using dual hydrophilic ligands was employed.
• Surface protection of InP-based QDs was achieved through ligand engineering.
• Optical properties and cellular imaging capabilities of the novel QDs were evaluated.

Main Results:

• A record photoluminescence quantum yield approaching unity was achieved for water-soluble InP QDs.
• Monoexponential decay dynamics and significantly suppressed blinking were observed in single QDs.
• The novel QDs demonstrated superior cellular imaging compared to organic dyes, with high photostability.

Conclusions:

• The developed dual hydrophilic ligand strategy enables high-performance, water-soluble InP QDs.
• These environmentally friendly QDs offer a promising alternative to cadmium-based emitters for biological imaging.
• The findings pave the way for advanced fluorescence labeling in biological and medical research.