Automated Analysis of Microplastics Using a Laser-Based Analyzer

Analyzing Microplastics in the Environment
Oral Presentation

Prepared by L. Tisinger
Agilent Technologies, 201 hansen ct., suite 108, wood dale, Illinois, 60191, United States


Contact Information: [email protected]; 630-306-7304

ABSTRACT

Recognition of microplastics as a significant environmental pollutant is a fairly recent development, and the means by which to analyze them are quickly developing. Larger plastic fragments, those greater than a millimeter, can be easily interrogated by physical and spectroscopic methods, e.g., visible microscopy, density, melting point, macro-infrared spectroscopy, etc. The latter, infrared spectroscopy, is a very good way to analyze particles, owing to the specificity of IR spectra; an IR spectrum is a molecular “fingerprint”. Microplastic particles, i.e., those that are less than a millimeter in diameter, require more complex methods. In order to measure them, they need to be found in a field of view, and then, using an appropriate spectrometric method, be measured/identified. Fortunately, there are now available technologies, including automated single-point infrared microscopes and imaging systems - both linear array and focal plane array - which streamline the process of collecting particle spectra. However, identification, via library searching, tends to be a distinct step in the MP workflow of these systems. Furthermore, utilizing infrared microscopes and imaging systems typically requires significant technical knowledge. To that end, a new system has emerged which automates the entire microplastics analysis workflow: a quantum cascade laser (QCL)-based analyzer. This presentation will (i) show details on the operation of the system, (ii) describe the simple microplastics analysis workflow, (iii) present some sample data, and show a new, direct filter analysis workflow.