Detection of microplastics in various environments by LIBS and Raman spectroscopy

presentation, poster

en

In perspective of recent news, where microplastics (MPs) were found even in human blood, the necessity to address the possible health risks and dangers for environment of MPs is rising. While possible dangers to life are being studied, we are looking for reliable method to detect MPs in environment. We have chosen to use various spectroscopic methods for the detection of MPs prepared to simulate effects of different environments on them. In this work we focus on the use of laser spectroscopy techniques – Laser Induced Breakdown Spectroscopy (LIBS) and Raman spectroscopy. We intended to benefit from the fact that LIBS yields mainly an atomic information of the sample and Raman spectroscopy focuses on molecular information. Our main goal is to detect the MP signal by both spectroscopy methods in every sample no matter the sample preparation. The samples were five different plastic types prepared in three different ways – grinded to necessary dimensions and left in pristine state, covered in algae and washed by fresh water, covered in algae and washed by waste water. All samples were measured individually by both spectroscopy techniques. The results are then visualized by using various approaches including Principal Component Analysis (PCA) and imaging. MP signals were detected by both techniques in every sample and thus the experiment was successful. These results could be used to propose detection of MPs in situ by LIBS, Raman spectroscopy, or both.

In perspective of recent news, where microplastics (MPs) were found even in human blood, the necessity to address the possible health risks and dangers for environment of MPs is rising. While possible dangers to life are being studied, we are looking for reliable method to detect MPs in environment. We have chosen to use various spectroscopic methods for the detection of MPs prepared to simulate effects of different environments on them. In this work we focus on the use of laser spectroscopy techniques – Laser Induced Breakdown Spectroscopy (LIBS) and Raman spectroscopy. We intended to benefit from the fact that LIBS yields mainly an atomic information of the sample and Raman spectroscopy focuses on molecular information. Our main goal is to detect the MP signal by both spectroscopy methods in every sample no matter the sample preparation. The samples were five different plastic types prepared in three different ways – grinded to necessary dimensions and left in pristine state, covered in algae and washed by fresh water, covered in algae and washed by waste water. All samples were measured individually by both spectroscopy techniques. The results are then visualized by using various approaches including Principal Component Analysis (PCA) and imaging. MP signals were detected by both techniques in every sample and thus the experiment was successful. These results could be used to propose detection of MPs in situ by LIBS, Raman spectroscopy, or both.

LIBS, Raman spectroscopy, microplastics, data fusion, PCA, classification

06.09.2022

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