Bright single-chain conjugated polymer dots embedded nanoparticles for long-term cell tracing and imaging

Area of Science:

• Nanotechnology
• Materials Science
• Biomedical Engineering

Background:

• Effective long-term cell tracing is crucial for understanding cancer progression and treatment efficacy.
• Current cell trackers face limitations in brightness, photostability, and multi-generational tracking capabilities.

Purpose of the Study:

• To develop novel conjugated polymer nanoparticles (CPNPs) for enhanced, long-term cancer cell tracing.
• To functionalize CPNPs with cell-penetrating peptides (TAT) for improved cellular uptake and retention.
• To evaluate the performance of TAT-CPNPs in terms of brightness, biocompatibility, and tracing duration.

Main Methods:

• Fabrication of CPNPs using a matrix-encapsulation method with tunable dot sizes.
• Surface modification of CPNPs with maleimide for efficient conjugation of TAT peptide via click chemistry.
• Characterization of CPNP fluorescence properties, including quantum yield (up to 32%).
• In vitro cell tracing experiments to assess brightness, biocompatibility, and generational tracking capacity.

Main Results:

• CPNPs exhibited tunable sizes and high fluorescence quantum yield (32%) at optimal concentrations.
• Maleimide functionalization facilitated robust conjugation of TAT peptide, preserving bioactivity.
• TAT-CPNPs demonstrated high brightness and excellent biocompatibility.
• Successful tracing of cancer cells for over 9 generations, surpassing the performance of commercial Qtracker 585.

Conclusions:

• The synthesized TAT-functionalized CPNPs are highly effective for long-term cancer cell tracing.
• These CPNPs offer superior brightness, biocompatibility, and extended tracing duration compared to existing technologies.
• The developed CPNP platform holds significant promise for advancing cancer research and diagnostics.