Microplastic quantification in environmental samples with complex organic matrices by diffusion NMR

With an increasing need in microplastic (MP) research there is also a persistent demand for further development of respective detecting and quantifying methods. To the current state, no technique is able to cover all different kinds of polymer types, instead valid characterisation is most likely to demand a combination of complementing approaches. In this regard, a promising technique introduced recently is quantitative nuclear magnetic resonance spectroscopy (qNMR), combining structural analysis of MP molecules with precise quantification. Despite various publications, however, qNMR is seldomly applied in environmental investigations. This study therefore, introduces an easy-to-apply preparation protocol for environmental qNMR analysis. It extends our recent efforts in MP fractioning by organic matrix removal, while at the same time transferring the method to more affordable benchtop devices. Finally, a semi-quantitative investigation of diffusion sequences is presented, enabling a more detailed analysis of MP mixtures in environmental samples.