Simple and Sensitive Multi-components Detection Using Synthetic Nitrogen-doped Carbon Dots Based on Soluble Starch

Area of Science:

• Materials Science
• Nanotechnology
• Analytical Chemistry

Background:

• Carbon dots (CDs) are versatile fluorescent sensors, but multi-component detection without surface modification remains a challenge.
• Nitrogen-doped carbon dots (NCDs) offer enhanced properties for sensing applications.

Purpose of the Study:

• To synthesize NCDs from soluble starch for multi-component sensing.
• To evaluate the sensing capabilities of NCDs for metal ions, ascorbic acid, and pH.
• To explore the potential of NCDs for real sample analysis and biological imaging.

Main Methods:

• One-pot hydrothermal synthesis of NCDs using soluble starch and phenylenediamine derivatives.
• Fluorescence spectroscopy for sensing Fe 3+, Ag +, and ascorbic acid (AA).
• Testing NCDs in real samples (tap water, Vitamin C tablets, orange juice) and for bacteria imaging.

Main Results:

• Successfully synthesized two types of NCDs (NCD-m and NCD-o).
• NCDs demonstrated sensitive fluorescence quenching for Fe 3+ (LOD 0.25 μM) and Ag + (LOD 0.51 μM).
• NCD-m showed indirect detection of AA (LOD 5.02 μM) and pH sensitivity (pH 2-13).
• NCDs were effective in analyzing real samples and showed potential for bacteria imaging due to their small size.

Conclusions:

• Easily synthesized NCDs enable multi-component detection without tedious surface modification.
• These NCDs are promising fluorescent probes for environmental monitoring, food analysis, and bioimaging.
• The one-pot synthesis method offers a scalable approach for producing functional NCDs.