Ligand-Engineered Hydrophilic Perovskite Enabling Surface Potential-Driven Anions Exchange for Multicolor Biosensing

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Designing zwitterionic ligands is crucial for water-dispersed perovskite nanocrystals (NCs).
• Applications in biosensing are limited by challenges in ligand design and NC dispersibility.
• Fast anion exchange (FAE) probes offer potential for sensitive detection.

Purpose of the Study:

• To propose a design paradigm for zwitterionic ligands.
• To understand the S_N2 reaction mechanism for ligand synthesis.
• To develop water-dispersible CsPbBr₃ NCs for FAE biosensing.

Main Methods:

• Investigated the S_N2 reaction mechanism between unsaturated alkylamines and haloalkanoic acids.
• Synthesized zwitterionic ligands using oleylamine (C18') and 5-bromovaleric acid (5-BVA).
• Utilized AgI nanoparticles (NPs) for a third FAE strategy in multicolor biosensing.

Main Results:

• Developed zwitterionic ligands that impart water dispersibility to CsPbBr₃ NCs.
• Achieved near 100% photoluminescence quantum yield and enhanced surface potential in NCs.
• Demonstrated multicolor biosensing capabilities for H₂S detection with wavelength shift and chromatic difference.

Conclusions:

• The proposed ligand design paradigm enhances NC water dispersibility and FAE efficiency.
• The developed FAE strategy enables sensitive and multicolor detection of analytes.
• Perovskite-based FAE probes show significant potential for applications in biological, environmental, and food safety analyses.