Polydopamine-encapsulated carbon dots to boost analytical performance for microplastics detection in fluorescence...

Area of Science:

• Environmental Science
• Materials Science
• Analytical Chemistry

Background:

• Microplastic pollution is a growing environmental concern.
• Accurate detection and quantification of microplastics are crucial for environmental monitoring.
• Existing detection methods can be complex and time-consuming.

Purpose of the Study:

• To develop a sensitive and rapid fluorescent detection method for polyethylene microplastics (MPs).
• To create a modified membrane using sulfur-doped carbon dots encapsulated with polydopamine (S-CDs@PDA) for enhanced MP detection.
• To enable the quantitative detection of MPs without relying on large-scale instrumentation.

Main Methods:

• Preparation of sulfur-doped carbon dots encapsulated with polydopamine (S-CDs@PDA).
• Construction of modified membranes using S-CDs@PDA for MP detection.
• Utilizing fluorescence response upon interaction with polyethylene MPs.
• Employing heating and vacuum filtration for membrane modification and MP detection.

Main Results:

• The S-CDs@PDA-modified membrane showed a 21.3% higher fluorescence signal and 8% higher detection efficiency for PE MPs compared to unmodified S-CDs membranes.
• A minimum detection limit of 4 mg for PE MPs was achieved.
• Rapid quantitative detection of PE MPs was realized within 10 minutes with a linear range of 4-14 mg.
• The modified membrane demonstrated excellent anti-photobleaching properties and effective sensing in real water samples.

Conclusions:

• The S-CDs@PDA-modified membrane provides an effective platform for the rapid and quantitative detection of polyethylene microplastics.
• This method offers a sensitive, reliable, and instrument-independent approach for microplastic analysis.
• The study presents a promising strategy for fluorescent tracing and quantification of microplastics, particularly smaller particle sizes.