Overview: The overall objective is to develop the first reliable technology to reproducibly and specifically identify and quantify individual nanoplastic particles. It will then be used, in collaboration with end-users, to accumulate data for various water, beverage and food samples, adding it to a virtually empty current database due to a lack of suitable techniques. To do so the ESR will develop, according to the size of the plastic particles studied, metallic porous membranes of various thicknesses and pore sizes using various microfabrication techniques. Thereafter a polarimetry setup, with a 45 degree incident angle to the normal of the membrane surface, similar to that used in FP7 Positive, will be used to measure both changes in the birefringence of the membrane and its SERS signals as micro and nanoplastic bind to the pore walls for their specific quantification.

Overview: The ESR2 will work on the construction of portable Photoluminescence (PL) absorption spectrometers. Initially, ESR2 will use information on optical signatures for different types and nano/micron plastics obtained from microfluidics knowhow. This will determine the most effective components for portable spectrometers such as the PL excitation laser, the type of USB spectrometers and the detection system, which will tune to the specific areas of resonant absorption/transmission and luminescence of plastic nanoparticles. These systems will be tested for the monitoring of water on site (Wessling).

Overview: The ESR at KTH will develop size based microfluidic continuous particle separation methods, based on inertial focusing. Inertial microfluidics is a passive, label-free separation method and both straight channel and spiral microfluidic devices with unique geometry to continuously focus and separate particles at a volumetric flow rates not reported in other microscale systems will be studied. In this project, inertial microfluidics will be applied for high throughput enrichment of micro and nanoplastics, primarily from water sample and then also in other matrices such as beverages (e.g. beer).

Overview: The ESR at KTH will develop filter based sample preparation strategy to separate micro- and nanoplastics from water, beverage (beer) and foodstuff (salt and honey). Two parallel routes will be investigated, one approach will be a stand-alone sample preparation module using filters with various pore sizes, and a second approach will use centrifugal microfluidics for integrated sample preparation. In collaboration with ESR3, the first stand-alone approach will be integrated and/or combined with inertial microfluidics to deliver different sized plastics for downstream analysis.  

Overview: The ESR at Bruker will develop a system for microplastics material identification and quantification by QCL-based infrared microscopy. The first work package is the setup of an initial prototype of a QCL-based microplastics analysis system. The system will be characterized with a focus on diffraction effects caused by the edges of the particles. A coherence reduction technique will be applied and characterized. State of the art analysis methods developed for FT-IR microscopes will be adapted and the feasibility of an application of these algorithms with a lower number of spectral channels will be examined. Depending on the results, the existing algorithms will be optimized or an alternative algorithm will be conceived and implemented. Finally the system will be tested at Aigues de Barcelona in cooperation with Aalborg University.

Overview: The ESR at WFSR will develop analytical methods to determine micro and nanoplastics in food products or additives, including honey, water, salt and beverages such as beer. The aim of this proposal is to improve analytical sample preparation and detection techniques for both micro and nanoplastics, and gain insight into the oral exposure of humans to environmentally relevant micro and nanoplastics. For this, reliable analytical methods will be developed and validated to detect them in complex matrices, based upon our extensive experience with engineered nanoparticles.

Overview: The ESR will develop and apply an optofluidic-based system to measure the concentration of various types of microplastics for which a combination of diffuse reflection spectroscopy and scattering will be used, while Raman spectroscopy will be applied to identify the types of plastic. After applying a size based microfluidic continuous particle separation method (in collaboration with ESR3), the sample under test will flow towards the sensing area on chip. All optical components for these three detection techniques will be integrated on the microfluidic chip to have at the end a low-cost, disposable chip into a handheld system for characterizing microplastics in beverage samples.

Overview: The ESR will design, fabricate and demonstrate the proof-of-principle of an SPR based optofluidic sensor for the detection of microplastics. The optics of a state-of-the-art SPR device will be optimized and a novel integrated lens design will be applied that allows in combination with other optical detection techniques noise reduction resulting in a low limit of detection. The free form lens will be fabricated in commercial polymers and functionalized prior to demonstrating the proof-of-principle for detecting microplastic particles

Overview: The ESR will develop and apply a multispectral imaging flow cytometry (mIFC) approach to assess microplastic particles in the size range between 2 and 40 µm based on their geometrical and colorimetric properties. ´Different affinities of plastic materials to dye molecules will be utilized to discriminate between microplastic materials. The number and size of microplastic particles will be detected as well to determine their content. Combined with appropriate separation and enrichment techniques mIFC can assess microplastics from various matrices such as seawater, sediments, food, drinks, plants and tissues.

Overview: The ESR will develop a high-throughput Raman microspectrometer with laser line excitation for analysis of microplastic particles on a substrate or in continuous flow. The laser excitation wavelength, spectrometer and detector will be selected that are most appropriate for Raman-based detection of coloured and non-coloured microplastics. Automation will include particle localization on the substrate before acquisition of Raman spectra. Acquisition of microplastic particles in a microfluidic chip will be synchronized with an image-based detection. A database of microplastics will be compiled and chemometric data analysis will classify the microplastic particles. Commercial databases will be tested as alternative approaches.

Overview: Micro and nanoplastics haven been shown to occur in drinking water, although the sources of the plastic particles are poorly understood, which could include the raw water supply, the water treatment plant, the public water distribution network, and the private networks inside buildings. Finally, it is poorly understood how many of the quantified microplastics come from contamination during the sampling and analysis itself. The ESR will investigate where the main sources for micro and nanoplastics are, and which mechanisms contribute to their formation in the drinking water supply systems.

Overview: Chemical analysis of micro- and nanoplastics in water creates a very large amount of highly complex data. For example, the number of spectra for FTIR or Raman imaging can go well into the millions per sample. The interpretation of these large datasets is labour intensive and subject to interpretation bias. Both are aspects that hamper the validity of micro- and nanoplastics analysis in increases the costs. ESR 12 will develop chemometric methods that help overcoming these issues, allowing a data analysis that is faster, more reliable and cheaper.

Overview: The ESR will conduct research on the development of a low cost platform exploiting vibrational spectroscopies for rapid and sensitive detection of micro- and nanoplastics. A range of different plasmonic nanostructures (metamaterials, nanorod arrays, and other optically active surface) in the scale of tens to hundreds of nanometers will be fabricated by micro- and nanofabrication techniques (e.g. electron beam lithography (EBL) and 3D nanoprinting technology). The platform can be incorporated into microfluidics and lab-on-a-chip components to facilitate sample pre-treatments, separation, and detection. The platforms will be fully validated and assessed against benchmarking techniques such as mass spectroscopy. This will equip the ESR with skills in materials synthesis and characterization, system integration, assay development and validation.

Overview: The ESR will study the ingestion, fate, and impact of micro-, nano-plastics to living cells. Different reporter gene assay (RGA) cell lines responsive to endocrine hormones will be used for the study. The student will develop several bioassays such as MTT assay using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (tetrazole) and AlamarBlue® assay to investigate the cell viability and cytotoxicity. In addition, high content analysis, reporter gene assays, and other hormone detection and quantifications approaches such as ELISA and mass spectrometry will be used to investigate adverse impacts of selected micro and nano-plastics on the living activities and hormone production. This project will provide useful and important information about the risk assessment of micro and nanoplastics, thereby to suggest any possible changes in the use of plastics in food industry and household commodities.