Targeted Analysis of Microplastics Using Discrete Frequency Infrared Imaging.

Area of Science:

• Analytical Chemistry
• Environmental Science
• Spectroscopy

Background:

• Microplastic contamination is a growing environmental concern.
• Current analytical methods for microplastic identification often suffer from low sample throughput.
• Efficient and rapid analysis is crucial for comprehensive microplastic monitoring.

Purpose of the Study:

• To develop and implement an analytical strategy for enhanced microplastic sample throughput.
• To utilize discrete frequency infrared imaging for targeted microplastic analysis.
• To demonstrate the effectiveness of the developed technique on both synthetic and environmental samples.

Main Methods:

• Development of a laser direct infrared chemical imaging system using a quantum cascade laser.
• Implementation of a discrete frequency infrared imaging technique for targeted particle selection.
• Application of the developed workflow to spiked samples and real environmental samples for microplastic identification.

Main Results:

• The targeted analysis successfully identified 87.7% of spiked polyethylene particles by scanning only 20% of the sample.
• Sample throughput was improved by at least a factor of 4 compared to conventional methods.
• Eight common microplastic types were correctly identified in environmental samples by analyzing less than 30% of the sample area.

Conclusions:

• The developed discrete frequency infrared image-based targeted analysis significantly enhances sample throughput for microplastic identification.
• This scanning strategy represents a substantial advancement in microplastic analysis efficiency.
• The technique shows potential for broad application across various infrared-based analytical platforms.