Best Practice for On-Filter Analysis of Microplastics Using the Agilent 8700 Laser Direct Infrared (LDIR) Chemical Imaging System

Význam tématu

The widespread presence of microplastics in water soil air and food chains has raised concerns about potential health and environmental impacts. These particles degrade from everyday plastic products and fall within the 1 to 5 mm size range. Accurate identification characterization and quantification of microplastics are essential for risk assessment monitoring environmental contamination and evaluating remediation strategies.

Cíle a přehled studie

This white paper outlines best practices for on filter analysis of microplastics using the Agilent 8700 Laser Direct Infrared LDIR chemical imaging system. It aims to guide analysts in minimizing contamination ensuring filter flatness optimizing filtration procedures and implementing robust data processing workflows for reliable polymer identification.

Pouzitá metodika a instrumentace

Methodology

• Laboratory cleanliness controls including laminar flow sample handling natural fiber lab coats and glassware cleaned with high purity water or ethanol
• Vacuum filtration using gold coated polyester filters with careful handling to maintain flatness within 10 um range
• Filter transfer and mounting in specialized filter holder with brass retaining ring to secure sample flatness
• On filter analysis with the Agilent 8700 LDIR chemical imaging system software Clarity Particle Analysis workflow with sensitivity and hit quality index thresholds for automatic detection and polymer identification
• Complementary analysis of larger fragments using Agilent Cary 630 FTIR spectrometer with diamond ATR module and MicroLab software for library guided identification

Instrumentation

• Agilent 8700 Laser Direct Infrared LDIR chemical imaging system
• Agilent Clarity instrument control software
• Sigma Aldrich vacuum filtration assembly
• Sterlitech gold coated PETG membrane filters and support materials
• Agilent Cary 630 FTIR spectrometer with diamond ATR module and MicroLab software

Hlavní výsledky a diskuse

The optimized workflow enables automated detection and classification of microplastic particles as small as 20 um. Hit quality index thresholds of 0.65 to 0.99 provide confidence levels for polymer matches classified as low medium or high. Particle counts size distributions and polymer composition are generated along with infrared and visible images. The use of blank controls supports quantification of background contamination and ensures data integrity. Complementary ATR FTIR analysis of larger particles aids in source attribution.

Přínosy a praktické využití metody

• High throughput reliable quantification of microplastics in environmental food and water samples
• Standardized protocols that reduce interlaboratory variability and improve comparability of data
• Minimal sample contamination through rigorous clean lab practices
• Integrated software reporting for streamlined data handling and customized reporting formats

Budoucí trendy a možnosti využití

Future developments may include integration of machine learning for improved particle classification expansion of spectral libraries to cover emerging polymers and additives development of standardized interlaboratory training programs and automation of sample handling steps. Coupling LDIR imaging with other analytical techniques such as Raman microscopy or mass spectrometry could enhance polymer characterization and additive profiling enabling deeper insight into microplastic sources and degradation pathways.

Závěr

The Agilent 8700 LDIR system combined with best practice sample handling and software workflows provides a robust platform for accurate on filter microplastic analysis. Adherence to contamination control flatness requirements and data quality thresholds ensures reliable polymer identification and quantification. Complementary ATR FTIR further aids particle source determination. Adoption of these protocols will advance monitoring efforts support regulatory compliance and facilitate global data harmonization.

Reference

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