Tailored hydrothermal platforms for fluorescent Q-dots with theranostic application

Area of Science:

• Materials Science
• Nanotechnology
• Photochemistry

Background:

• Fluorescent materials from hydrothermal reactions of citric acid and urea are gaining attention.
• The formation process and chemical structures of these fluorescent products are not fully understood.

Purpose of the Study:

• To investigate the fluorescence properties of hydrothermal reactions involving citric acid and urea.
• To elucidate the formation pathways and chemical structures of resulting fluorescent species.
• To understand the influence of reaction conditions on fluorescence evolution.

Main Methods:

• Hydrothermal synthesis of fluorescent materials from citric acid and urea.
• Spectroscopic techniques for chemical identification (e.g., acid treatment).
• Comparative analysis with graphene quantum dots and citrazinic acid.

Main Results:

• Under mild conditions, fluorescence originates from citrazinic acid.
• Fluorescence shifts towards carbonized quantum dots (CDs) with increasing temperature and reaction time.
• Differences in excitation-dependency, photobleaching, and fluorescence lifetime were observed compared to graphene quantum dots and citrazinic acid.

Conclusions:

• Provides a detailed understanding of fluorescent species evolution by tuning reaction conditions.
• Identifies citrazinic acid and carbonized quantum dots (CDs) as key fluorescent products.
• Suggests potential applications in nanotechnology and theranostics.