Chemical Imaging of Microparticles with Raman, FTIR and Quantum Cascade Laser Microscopy

Microplastic contamination of the environment and ecosystem has attracted much attention in recent years. Its presence has been detected in the most remote regions and its propagation through the food chain poses a serious health risk to humans and animals. To better understand their presence in the environment, their detection and identification plays a critical role in any remediation effort. FTIR and Raman imaging provide simultaneously size metrology and spectral information and have been gold standard tools for microplastic analysis. In this study, we will present state-of-the-art chemical imaging methods, Fourier transform infrared spectroscopy (FTIR) and Raman imaging as well as quantum cascade laser mapping, for the detection of microplastic particles. We will demonstrate enhanced detection through the use of reflective substrates and discuss the signal enhancement strategies of these chemical imaging techniques as well as their limitations.