We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Detection and Characterisation of Micro- and Nano-plastics in Water using Optical Spectroscopy
AI summary Read the abstract
This thesis explored photoluminescence spectroscopy as an alternative technique for detecting and characterizing micro- and nanoplastics in water, optimizing fluorescence excitation-emission features and comparing performance against conventional spectroscopic approaches.
Micro- and nanoplastic (MNP) contamination in various environmental matrices has become an increasing global concern due to its potential ecological and health impacts. However, detecting and characterising these minuscule plastic particles remains challenging due to the limitations of conventional spectroscopic techniques. This thesis explores the potential of photoluminescence (PL) spectroscopy as an alternative technique for detecting and characterising MNPs in aqueous media. The research encompasses the optimisation of fluorescence excitation-emission (FLE) features for MNP detection, the development of a protocol for generating model MNPs, and the proof-of-concept demonstration of a semi-portable PL spectrometer for microplastic detection. In the first set of experiments, Fluorescence (FL) spectroscopy was utilised to investigate the intrinsic excitation-emission features of common microplastics, including polystyrene (PS), polyethylene terephthalate (PET), and polypropylene (PP). Through systematic analysis, distinct fluorescence signatures were identified for each polymer type, enabling precise and label-free identification. These spectral characteristics, linked to polymer-specific molecular transitions, form the basis for a non-destructive fluorescence-based microplastic detection method. The second set of experiments established a protocol for generating model MNPs through a high-power direct ultra-sonication technique. This method significantly improved the efficiency of MNP production compared to conventional methods, eliminating the need for chemical additives and achieving high suspension stability in an aqueous medium. The generated MNPs, ranging from 100 nm to 150 μm, closely resembled environmental plastic pollutants in terms of size distribution and morphology. Their characterisation using Raman spectroscopy, infrared spectroscopy combined with machine learning, UV-Vis spectroscopy, and SEM imaging confirmed their suitability as reference materials for microplastic research. Furthermore, the third phase of the study examined the effectiveness of FLE mapping for detecting and characterising MNPs in aqueous media. The study demonstrated that ultrasonicated MNPs, including PS, PET, and PP exhibited strong and distinct FL spectra, including those smaller than 100nm. This study confirmed that optimised excitation wavelengths provide distinct FL fingerprints for MNPs and enhance their FL signal strength, improving the technique's sensitivity for real-time detection. Finally, the development of a semi-portable PL spectrometer further highlighted the feasibility of real-time, on-site MNP detection. Although challenges such as background noise require further optimisation, this proof-of-concept system represents a significant step toward field-deployable MNP pollution monitoring.
More Papers Like This
Optical spectroscopy for the detection of micro- and nanoplastics in water
AI summary Read the abstract
This paper reviews optical spectroscopy techniques for detecting and identifying micro- and nanoplastics in water. Researchers present several methods that provide additional analytical dimensions beyond classical approaches for characterizing plastic contaminants.
Optical measurement technologies for detecting low levels of pollution and identifying microplastics in water
AI summary Read the abstract
Researchers reviewed optical technologies for detecting and identifying microplastics in water, experimentally characterizing the fluorescence spectra of PE and PET microplastic samples under 365 nm excitation and identifying spectral bands enabling identification of different polymer types, then proposing a comprehensive hardware solution using a fluorescent probe for microplastic visualization.
Exploring the potential of photoluminescence spectroscopy for the detection of microplastics
AI summary Read the abstract
This study explored the use of photoluminescence spectroscopy — where plastic particles fluoresce under light excitation — as an alternative to FTIR and Raman spectroscopy for detecting and characterizing microplastic and nanoplastic particles in various environmental matrices. The technique showed potential as a faster screening method for identifying plastics in water, food, and other samples.
Could photoluminescence spectroscopy be an alternative technique for the detection of microplastics? First experiments using a 405 nm laser for excitation
AI summary Read the abstract
First experiments using a 405 nm laser show that photoluminescence spectroscopy can reliably distinguish plastic materials from natural marine substrates based on their spectral emission profiles. This technique could offer a faster, lower-cost complement to Raman and FTIR spectroscopy for detecting microplastics in environmental samples.
Outlook on optical identification of micro- and nanoplastics in aquatic environments
AI summary Read the abstract
Researchers studied the optical properties of micro- and nanoplastics and evaluated near-infrared spectroscopy as a detection method for plastic particles in water, finding that optical techniques show promise for rapid, non-destructive identification. Improved optical detection methods could enable faster and more cost-effective monitoring of plastic pollution in aquatic environments.
Research digests by email
When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.