Carbon quantum dots modified with hyperbranched polyglycerol for bioapplications: improved photostability and...

Area of Science:

• Nanotechnology
• Biomedical Engineering
• Materials Science

Background:

• Accurate intracellular temperature measurement is crucial for understanding cellular processes.
• Carbon quantum dots (CQDs) show potential for intracellular thermometry but suffer from photobleaching and environmental interference.
• Existing CQD sensors face challenges with accuracy due to external factors like pH and biomolecules.

Purpose of the Study:

• To develop a robust and accurate nanothermometer for precise intracellular temperature measurements.
• To enhance the photostability and environmental resilience of CQDs for biological applications.
• To investigate the efficacy of surface modification using hyperbranched polyglycerol (HPG) on nitrogen- and sulfur-doped CQDs (N,S-CQDs).

Main Methods:

• Synthesized nitrogen- and sulfur-doped CQDs (N,S-CQDs).
• Modified N,S-CQDs with hyperbranched polyglycerol (HPG) to create N,S-CQD-HPG.
• Evaluated the photostability, environmental robustness, and temperature sensing performance of N,S-CQD-HPG in simulated biological conditions.

Main Results:

• HPG modification significantly improved the photostability of N,S-CQDs by suppressing surface fluorescence.
• The modified N,S-CQD-HPG exhibited enhanced robustness against environmental variations (pH, ions, viscosity, biomolecules).
• N,S-CQD-HPG demonstrated reliable and repeatable temperature sensing capabilities suitable for complex biological environments.

Conclusions:

• Strategic surface functionalization of CQDs is essential for developing reliable nanometric temperature sensors.
• HPG-modified N,S-CQDs offer a promising solution for accurate and stable intracellular thermometry.
• This approach advances the development of advanced nanosensors for diverse biological and biomedical applications.