Biocompatibility of Metal–Phenolic Network-Coated Nanoparticles †
1
Laboratory of Environmental Toxicology, National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618 Tallinn, Estonia
2
School of Natural Sciences and Health, Tallinn University, Narva mnt. 25, 10120 Tallinn, Estonia
*
Authors to whom correspondence should be addressed.
†
Presented at the International Conference EcoBalt 2023 “Chemicals & Environment”, Tallinn, Estonia, 9–11 October 2023.
Proceedings 2023, 92(1), 33; https://doi.org/10.3390/proceedings2023092033
Published: 22 November 2023
(This article belongs to the Proceedings of International Conference EcoBalt 2023 "Chemicals & Environment")
Metal–phenolic networks (MPNs) are novel adsorbent materials that have promising applications in the environmental remediation of organic pollutants and heavy metals. For efficient adsorption, the specific surface area of MPN materials can be increased by coating nanoparticle surfaces with MPNs. Such MPN-coated nanoparticles may prove very efficient in various environmental applications; however, their safety needs to be tested at the early stages of material development. Here, free-living freshwater-ciliated protozoa were used as model organisms for testing the biocompatibility of iron–tannic acid network-coated Au nanoparticles (Fe–TA@Au NPs). Viability after 24 h Fe–TA@Au NP exposure was measured using an ATP assay kit, and intracellular reactive oxygen species (ROS) were quantified using 2′,7′-dichlorodihydrofluorescein diacetate (H2DCFDA) [1]. Microscopy was used to qualitatively characterize the swimming behavior of protozoa as well as the uptake and depuration of Fe–TA@Au NPs in the ciliates. The results showed that Fe–TA@Au NPs were not lethal to the protozoa at the maximum concentration tested (~1010 particles/mL). Despite MPN-coated NP phagocytosis by protozoa and accumulation in food vacuoles, the MPNs did not affect the swimming behavior or viability during 24-h exposure. To test the performance of the novel materials as heavy metal toxicity-mitigating agents, co-exposures of protozoa to Fe–TA@Au NPs and toxic levels of copper salt (CuSO4, LC50~3 mg/L) were conducted. Fe–TA@Au NPs completely rescued the protozoa from cell death induced by CuSO4. The underlying mechanism of toxicity mitigation could have been the removal of Cu ions by MPNs or the tannic acid in the MPNs acting as an antioxidant, as evidenced by reduced levels of ROS in the protozoa. Thus, the study showed that the effective levels of Fe–TA@Au NPs were biocompatible with unicellular freshwater model organisms and have potential for applications in metal contamination remediation in aqueous environments.
Author Contributions
Conceptualization, M.M.; methodology, A.V.; investigation, A.V.; writing—original draft preparation, A.V.; writing—review and editing, M.M. and K.K.; project administration, M.M.; funding acquisition, M.M. All authors have read and agreed to the published version of the manuscript.
Funding
This research was funded by the Estonian Research Council, grant number STP28.
Institutional Review Board Statement
Not applicable.
Informed Consent Statement
Not applicable.
Data Availability Statement
Data supporting reported results will be made available upon request.
Acknowledgments
The authors thank Heiki Vija for their assistance with chemical analysis and Maarja Otsus for their assistance with microscopy.
Conflicts of Interest
The authors declare no conflict of interest.
Reference
- Juganson, K.; Mortimer, M.; Ivask, A.; Pucciarelli, S.; Miceli, C.; Orupõld, K.; Kahru, A. Mechanisms of toxic action of silver nanoparticles in the protozoan Tetrahymena thermophila: From gene expression to phenotypic events. Environ. Pollut. 2017, 225, 481–489. [Google Scholar] [CrossRef]
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MDPI and ACS Style
Välimets, A.; Koort, K.; Mortimer, M. Biocompatibility of Metal–Phenolic Network-Coated Nanoparticles. Proceedings 2023, 92, 33. https://doi.org/10.3390/proceedings2023092033
AMA Style
Välimets A, Koort K, Mortimer M. Biocompatibility of Metal–Phenolic Network-Coated Nanoparticles. Proceedings. 2023; 92(1):33. https://doi.org/10.3390/proceedings2023092033
Chicago/Turabian StyleVälimets, Anett, Kairi Koort, and Monika Mortimer. 2023. "Biocompatibility of Metal–Phenolic Network-Coated Nanoparticles" Proceedings 92, no. 1: 33. https://doi.org/10.3390/proceedings2023092033
