Supra-Carbon dots for methyl-paraoxon detection using a new controllable IFE-based method.

Area of Science:

• Materials Science
• Analytical Chemistry
• Biomedical Engineering

Background:

• Pesticide residues present a significant human health risk.
• Inner filter effect (IFE) offers rapid, cost-effective fluorescent detection but faces challenges like low spectral overlap and impurity interference.

Purpose of the Study:

• To develop novel aggregation-induced emission (AIEE)-type carbon dots (CDs) to enhance IFE-based strategies.
• To create a multi-channel detection platform for reliable fluorescent probes in real samples and imaging applications.

Main Methods:

• Synthesized novel nitrogen and sulfur-doped carbon dots (N, S-CDs) using p-PA and thiourea.
• Verified the AIEE characteristics of the synthesized Supra-CDs.
• Evaluated the detection performance, practical applicability, and imaging capabilities of Supra-CDs in an IFE-based strategy.

Main Results:

• Supra-CDs exhibited a significant fluorescence intensity increase (nearly 360%) in water compared to N, S-CDs.
• Improved spectral overlap from 1.80% to 33.11% in the IFE system, demonstrating superior performance in aqueous solutions.
• Achieved a linear detection range of 0.5-100 μM with a 0.5 μM detection limit for methyl paraoxon using a smartphone-based system and demonstrated cell imaging of intracellular lipids.

Conclusions:

• Introduced a new class of Supra-CDs with AIEE properties and a tunable IFE fluorescent sensor.
• Demonstrated the potential of AIEE-type Supra-CDs for sensitive detection and advanced imaging applications.