Carbonized Polymer Dots as Versatile Nanocarrier for Bioincompatible Fluorophore Imaging.

Area of Science:

• Materials Science
• Biotechnology
• Nanotechnology

Background:

• Cell permeability is a major limitation for many high-performance fluorophores in bioimaging.
• Existing fluorescence probes often struggle to cross cell membranes effectively, hindering their application.

Purpose of the Study:

• To develop a versatile platform for delivering impermeable fluorophores into cells.
• To overcome the cell permeability barrier for enhanced fluorescence bioimaging and theranostics.

Main Methods:

• Development of carbonized polymer dots (CPDs-280) as a noncovalent translocation platform.
• Formation of stable nanocomplexes with impermeable fluorophores, including HECA, ESY-Na+, and ESY.
• Demonstration of carrier-dominated intracellular localization and cargo-agnostic delivery.

Main Results:

• CPDs-280 successfully complexed with and delivered various impermeable fluorophores into the cytosol.
• The platform demonstrated a high loading capacity (∼50.8%) and overrode innate targeting signals of dyes.
• Intracellular luminescence was achieved with previously inert membrane-impermeable amphiphilic dyes upon complexation.

Conclusions:

• Carbonized polymer dots provide a generic, noncovalent strategy to enhance fluorophore cell permeability.
• This approach unlocks a vast range of underutilized fluorescent probes for advanced bioimaging.
• The CPD platform holds significant potential for future theranostic applications.