In the summer of 2024, Dr. Sophia Hohenstatt from Heidelberg University Hospital’s Department of Neuroradiology was planning a pilot study to compare microplastic concentrations in the blood of ischemic stroke patients and healthy controls. Since few laboratories are equipped to reliably quantify microplastics in complex biological matrices, she initially struggled to find an analytical partner for the project.
Dr. Hohenstatt eventually contacted Measurlabs, which offered the combination of technical expertise and responsive service she was looking for. In addition to providing the analyses, Measurlabs’ team advised Heidelberg researchers on method selection, sampling, and logistics. The collaboration resulted in a fully plastic-free sampling and analysis protocol that provides a solid methodological foundation for future research.
Preliminary support for a connection between microplastic levels and stroke history
Hohenstatt et al.’s study, published in the European Stroke Journal, provides tentative evidence of an association between circulating microplastic levels and ischemic stroke. Although the results were not statistically significant when comparing the within-study cohorts—likely due to the limited sample size of 20 patients and 15 controls—both median and mean particle counts were higher among stroke patients.
Table 1: Number of microplastic particles by study cohort
Group | n (%) | Median (interquartile range), MPs/mL | Mean ± standard deviation, MPs/mL | Range (Min-Max), MPs/mL |
Stroke | 20 (57.1) | 13.5 (6-23) | 13.95 ± 8.73 | 1-28 |
Healthy | 15 (42.9) | 7 (2-18) | 10.80 ± 10.98 | 0-35 |
To compensate for limited statistical power, the researchers conducted an additional pooled analysis with data from two prior studies based on similar methodologies.
"This pooled comparison provides stronger support for a link between microplastic levels and ischemic stroke, as stroke patients exhibited significantly higher mean microplastic concentrations. However, due to dataset heterogeneity, larger harmonized studies are required to confirm the results," Dr. Hohenstatt says.
Plastic-free study design with a reproducible µFTIR analysis workflow
The protocol that Heidelberg University researchers and Measurlabs experts developed for the pilot study lays a strong foundation for future confirmatory research, as it minimizes external contamination and is based on reproducible and well-documented methodology.
"From the start, we all agreed that every stage should be strictly plastic-free," says Testing Expert Joshua Reeder. "To ensure this, we advised the Heidelberg team on sourcing glass and metal equipment, and implemented rigorous contamination-control measures throughout the actual testing phase."
Micro-Fourier transform infrared (µFTIR) imaging was chosen as the analysis method for its ability to reliably identify and quantify microplastic particles by size range and polymer type. Pyrolysis-GC/MS was also considered, as it has been used in some of the most-cited prior studies and can detect smaller particles, down to the nanoplastic size range.
"We eventually decided that obtaining particle size information was more valuable, as it was uncertain whether the likely very small nanoplastic concentrations would exceed the detection limit of py-GC/MS," Dr. Hohenstatt explains. "Previous interlaboratory comparison studies also suggest that µFTIR can yield reproducible results across laboratories, so we concluded that using it would allow us to contribute to the growing dataset for future pooled studies."
Ongoing collaboration built on seamless communication and technical expertise
The collaboration between Measurlabs and Heidelberg University has now continued for close to two years, starting with methodological discussions in the summer of 2024 and culminating in the analysis of the 35 pilot study blood samples in the fall of 2025 and the publication of the study in May 2026. Beyond this study, Measurlabs has also supported Heidelberg researchers in a separate project in which saline solutions were analyzed for microplastics, nanoplastics, and PFAS compounds to evaluate potential leaching from catheters.
Dr. Hohenstatt has been highly satisfied with the service her team has received across both projects.
"Communication with Josh and his colleagues has been very smooth throughout. They always come to meetings well prepared and answer our questions quickly, with an evidently high level of technical expertise," she says.
The researchers also value the step-by-step support with logistics and packaging, particularly given the number of factors involved in packing and shipping temperature-controlled biological samples internationally.
"All these things make us want to come back to Measurlabs with future analysis needs, even with services that we could find elsewhere," Dr. Hohenstatt concludes.