Seznam abstraktů 2025: POSTEROVÁ SEKCE D

Understanding the mechanistic nanoparticle-induced toxicity is important for predictive risk assessment. The aim of the paper was to perform a trend-based analysis of four key cellular stress markers — mitochondrial membrane potential (MMP), cell membrane damage (CMD), nuclear size (NS), and nuclear intensity (NI) — in response to increasing doses of six widely used engineered nanomaterials: silver (Ag), zinc oxide (ZnO), copper (Cu), cerium dioxide (CeO₂), silicon dioxide (SiO₂), and titanium dioxide (TiO₂).
The responses were evaluated on three mammalian cell lines HEPG2, HepaRG and RAW264.7. With increasing doses:
- MMP was significantly affected by Cu and ZnO, indicating mitochondrial dysfunction
- CMD showed an increasing trend of membrane stress almost for all compounds, displaying reliability as an early toxicity predictor
- NI generally increased with exposure, except Cu where the trend was negative, potentially reflecting chromatin condensation.
- NS displayed visible divergent trends: Cu induced nuclear shrinkage, while ZnO exposure was associated with nuclear enlargement, hinting at compound-specific nuclear effects.
Notably, for cell lines, although the sensitivity of each cell line was different, the trends were consistent, indicating universal cellular pathways.
By isolating trend directions and magnitudes across diverse cellular contexts and nanoparticle types, this study brings the value of a multivariate, marker-driven approach to nanoparticle hazard profiling. These mechanistic patterns highlight the potential of CMD, MMP, NI, and NS as early-response biomarkers, enabling more informative and rapid screening strategies in nanotoxicology.
ACKNOWLEDGEMENTS: Tomas Bata University in Zlín is acknowledged for all support provided in kind.
FUNDINGS: The Ministry of Education, Youth and Sports of the Czech Republic supported this study financially within the framework of DKRVO (project number RP/CPS/2024-28/007).

Recent developments have highlighted the exceptional physical, optical, magnetic, and electrical properties of spinel ferrite magnetic nanoparticles (MNPs), which have attracted significant interest for applications in magnetic fields, microwave absorption, and biomedicine. However, data on their potential health risks remain scarce.
Our study assessed the (geno)toxic potential of three zinc- and/or manganese-doped MNPs: γFe2O3, Zn0.7Fe2.3O4, and Mn0.4Fe2.6O4 using a 3D cell model (spheroids) derived from the human hepatocellular carcinoma cell line (HepG2).
Cytotoxicity was evaluated by measuring intracellular ATP levels, while genotoxicity was assessed by the comet assay and flow cytometry targeting γH2AX (for double-strand breaks) and pH3 (for mitotic cells), markers of clastogenic and aneugenic activity, respectively. In addition, generation of reactive oxygen species (ROS) was measured by DCFH-DA assay, whereas the influence on DNA damage and oxidative stress response genes was analysed by qPCR. Transmission electron microscopy (TEM) was used to investigate nanoparticle internalisation.
Spheroids were exposed to up to 250 µg/mL MNPs for 2 to 96 hours. Zn0.7Fe2.3O4 and Mn0.4Fe2.6O4 exhibited higher cytotoxicity than γFe2O3 at 24 and 96 hours. While the comet assay indicated significant DNA damage after 96 hours, no increase in γH2AX or pH3 levels was detected. A dose- and time-dependent increase in ROS generation was observed only for γFe2O3. Gene expression remained largely unchanged, except for consistent MYC downregulation across all MNPs at 24 hours. TEM analysis confirmed MNPs penetration into the peripheral regions of the spheroids.
Our findings contribute towards safer use of MNPs in biomedical and other applications.
Funding: H2020-MSCA NESTOR (101007629), HE CutCancer (101079113), ARRS P1-0245 and J1-4395, and ARIS MR grant to IR.

Metallic nanoparticles, particularly zinc oxide nanoparticles (ZnONPs), are innovative tools for modulating the metabolic activity of photosynthetic microorganisms and are increasingly used in bionanotechnology. The morphology of nanoparticles significantly influences their interaction with biological systems and the resulting effects, making the study of their properties essential for the development of biotechnological applications.
In this study, the effects of lab-synthesized ZnONPs with multipod morphology, were compared with those of commercially available spherical ZnONPs (Sigma-Aldrich) on the cyanobacterium Arthrospira platensis (spirulina). Nanoparticles were added to the spirulina culture at the beginning of the exponential growth phase (day 3), in two concentration ranges: 0.01-1.0 mg/L and 10-30 mg/L. To evaluate the cyanobacterial response to nanoparticle interaction, two parameters were assessed at the end of the cultivation cycle (day 7): accumulated biomass and C-phycocyanin content, a photosynthetic pigment with high biotechnological value.
The results demonstrated that both ZnO multipods and spherical ZnONPs stimulated biomass production by 12-14% at higher concentrations. However, a marked difference in pigment response was observed. Spherical nanoparticles caused a substantial reduction in C-phycocyanin content by 57.5-87.9%, whereas multipod ZnONPs stimulated pigment synthesis at low concentrations and exerted a weaker inhibitory effect at high concentrations (50.3-59.7%).
ZnONP morphology significantly modulates pigment biosynthesis and cytotoxicity in Arthrospira platensis, with multipod structures showing a more favorable interaction profile. These data support the morphological optimization of metal oxide nanoparticles for use in controlled cyanobacterial cultivation systems.
ACKNOWLEDGEMENTS: This research was funded by National Agency for Research and Development, Republic of Moldova, Project 25.80012.7007.26 SE” ZnONP Morphology in Interaction with Photosynthetic Microorganisms - Effects and response Mechanisms”.

Recently, nanosized graphene oxide (GO) has gained significant scientific interest for biomedical strategies. However, prior to their application GO nanomaterials should be proved as safe and biocompatible. Therefore, in this study we have examined the in vivo effects of pristine and polyethylene glycol-modified GO (GO-PEG) nanoparticles in male hooded rats, following intraperitoneal administration (4 mg/kg body weight, eight doses over four weeks). We found that GO-PEG reduced only hematocrit levels while the other blood parameters remained unaffected. Liver and kidney functions were evaluated by the serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT), and serum and urine creatinine and urea nitrogen. Both GO and GO-PEG significantly retarded gain and reduced 18-hour diuresis. The calculated organ coefficients of the treated animals revealed significant augmentation of the mean liver, kidney, and spleen weights, while reduced testes weights. Increased serum AST, ALT, and creatinine, and creatinine and urea nitrogen in the urine were measured in both treated groups indicating potential hepatorenal toxicity. The treated rats exhibited higher serum glucose levels. These results suggest that repeated exposure to GO and GO-PEG nanoparticles may adversely affect the homeostasis and therefore further studies on the mechanisms underlying these toxicological effects are needed.
Acknowledgement: The support of the Centre of Competence “Sustainable Utilization of Bio-resources and Waste of Medicinal and Aromatic Plants for Innovative Bioactive Products” (BIORESOURCES BG), project BG16RFPR002-1.014-0001, funded by the Program “Research, Innovation and Digitization for Smart Transformation” 2021-2027, co-funded by the EU, is greatly acknowledged.

Despite the recent interest in the nanocarbon-based biomaterials, their safety for in vivo application remains insufficiently understood. Our study evaluated the effects of subchronic exposure to graphene oxide (GO) and GO nanoparticles, modified with polyethylene glycol (GO-PEG), on the motor activity of male Long Evans rats. After eight intraperitoneal injections at a dosage of 4 mg/kg body weight, a set of behavioral tests was performed, including an open field to assess the rats’ general locomotor activity and a rotarod test to evaluate the motor coordination. Serum levels of creatine kinase (CK) were determined as the most sensitive indicator of muscle damage. Blood and urine levels of creatinine and urea were also measured to assess renal function. Lower locomotor activity was found in the GO and GO-PEG groups as shown by the decreased number of line crossings in the open field, while impaired coordination was not observed in the rotarod results. The treated rats showed a significant increase of serum CK and creatinine levels along with higher levels of creatinine and urea in their urine. These findings suggest possible muscle-related complications after GO and GO-PEG exposure with a potential to trigger failure in other organs, particularly kidneys, warranting further investigation into nanoparticles’ long-term biosafety.
Acknowledgement: The support of the Centre of Competence “Sustainable Utilization of Bio-resources and Waste of Medicinal and Aromatic Plants for Innovative Bioactive Products” (BIORESOURCES BG), project BG16RFPR002-1.014-0001, funded by the Program “Research, Innovation and Digitization for Smart Transformation” 2021-2027, co-funded by the EU, is greatly acknowledged.

The antioxidant activity assessed using the ABTS assay can serve as an indirect marker of moderate oxidative stress, specific to adaptive physiological responses. This study aimed to evaluate the influence of copper nanoparticles (CuNPs), copper oxide nanoparticles (CuONPs), zinc oxide nanoparticles (ZnONPs), and titanium dioxide nanoparticles (TiO2NPs) on the antioxidant activity of the cyanobacterium Arthrospira platensis (spirulina), using the ABTS method. The cyanobacterium was cultivated in mineral medium supplemented with two concentration ranges of nanoparticle: low (0.01-0.5 mg/L) and high (1.0-20 mg/L). Antioxidant activity was measured in both aqueous and ethanolic extracts of the resulting biomass. The results revealed that aqueous extracts exhibited a significant increase in antioxidant activity (77.6-95.3% ABTS inhibition) at higher concentrations of CuNPs, CuONPs, and ZnONPs, following a clear concentration-dependent trend. In ethanolic extracts, the response was more variable: CuNPs induced a moderate increase in antioxidant activity, while CuONPs caused a decrease. TiO2NPs showed relatively stable antioxidant values across all tested concentrations, with minimal variation between solvents. The study demonstrates that metal-based nanoparticles modulate the antioxidant mechanisms of Arthrospira platensis, triggering adaptive responses to oxidative stress, with effects depending on the nanoparticle type, dose, and type of extract. Extracts obtained from exposed biomass may be considered valuable functional products with biotechnological potential. This research was funded by the MINISTRY OF EDUCATION AND RESEARCH OF REPUBLIC OF MOLDOVA, Research Subprogram 020101 ”InBioS”.

Layered double hydroxides (LDHs) are anionic nanoclays consisting of positively charged mixed-metal hydroxide layers intercalated with anions and water molecules. Because of their anionic exchange capacity and adsorption properties, LDHs have attracted attention for their potential in removing pollutants, including heavy metals, from the aquatic environment. Cadmium is one of the metals that can induce adverse biological effects even at low concentrations, particularly in the nervous system. Our study aimed to evaluate the potential of calcined zinc-aluminium LDH-nitrate (c-Zn Al LDH NO3) and calcined magnesium-aluminium LDH-nitrate (c-Mg Al LDH NO3) to prevent cadmium-induced toxicity in zebrafish (Danio rerio) early life stages.
We measured mortality, malformations, and hatching rate after exposure of Danio rerio embryos and larvae to cadmium alone and in combination with 100 mg·l-1 c-Zn-Al LDH-NO3 or c-Mg Al LDH-NO3 following the OECD 236 guideline. The molecular changes at DNA level were assessed using a comet assay.
Cadmium exposure at tested concentrations after 24-96 h resulted in significant developmental malformations, including pericardial edema, incomplete yolk sac absorption, and tail deformities. Furthermore, DNA damage was observed after 96 h of exposure to the LC50 concentration of cadmium. Notably, co-exposure with c-Mg-Al LDH-NO3 substantially reduced cadmium toxicity, whereas c-Zn-Al LDH-NO3 did not demonstrate a comparable protective effect. These findings suggest that c-Mg-Al LDH-NO3 holds promise as a nanomaterial for reducing cadmium toxicity in aquatic environment. Further testing is needed to unveil why the other nanomaterial was not so effective.

The development, production, and environmental presence of inorganic fibers of various diameters is steadily increasing worldwide implying raising concerns about their potential ecological safety. Despite their growing use, there is still a lack of comprehensive data on their effects on freshwater organisms.
Titanium dioxide is widely utilized across industry due to its excellent properties. In this study, newly synthesized TiO2 rutile fibers with an average diameter in the sub-micrometer range produced via centrifugal spinning were evaluated for their potential ecotoxicological effects in zebrafish (Danio rerio) early life stages, i.e. eggs and larvae, as a biological model.
The fibers were tested across 0-100 mg·L-1 concentration range. We assessed developmental toxicity (i.e. malformations), biochemical responses (i.e. markers of oxidative stress and neurotoxicity), and molecular alterations at DNA level in zebrafish larvae following exposure.
The results showed no observable developmental malformations or statistically significant biochemical or molecular changes in exposed zebrafish larvae. Based on our findings, the tested TiO2 rutile fibers can be considered as non-toxic to Danio rerio under the given experimental conditions.
ACKNOWLEDGEMENT: This study follows prior work by Bacova et al. (Environ. Sci.: Nano 9, 2022) and was supported independently under the FCHT/SGS/2025/004 project.

Polyacrylonitrile (PAN) electrospun nanofibers are promising for use in protective clothing due to their non-toxic character, large surface area, high porosity, and chemical resistance. Incorporation of nanoparticles into polymeric nanofibers can provide them with additional functionalities, such as antimicrobial, chemical or radiation protection. In this study, PAN nanofibers were functionalized with various photocatalytic nanoparticles, namely with 15% TiO₂, Ce₂O₃, Er₂O₃, or WO₃, to produce multifunctional hybrid materials. FTIR, SEM, and TGA were used to verify morphology and presence of the nanoparticles within the fibers. Given their potential use in skin-contact textiles (e.g., masks, protective garments), we performed in vitro biocompatibility evaluation. Murine 3T3 embryonic fibroblasts were exposed to 24-hour leachates obtained from nanofibers incubated in cell culture medium, and to controls (PAN and cell culture medium). After 24- and 72-hour incubation, cell viability, morphology, and metabolic activity were assessed by live/dead fluorescence staining, light microscopy, and MTS assay, respectively. All samples maintained >90% cell viability compared to control cells, indicating absence of cytotoxicity. Dynamic light scattering analysis did not show release of nanoparticles from the fibers into distilled water nor phosphate buffer saline. Altogether, these results demonstrate that hybrid PAN nanofibers with incorporated TiO₂, Ce₂O₃, Er₂O₃, or WO₃ nanoparticles are biocompatible and stable, supporting their potential for use in protective materials designed for direct skin contact.
The project was funded by the European Union European Defence Fund, EDF-2021-OPEN-R-2 call, under grant agreement 101110262, project Nano-SHIELD, and by MEYS of the Czech Republic (ExRegMed CZ.02.01.01/00/22_008/0004562, and RI NanoEnviCz LM2023066).

Electrospun nanofibrous materials have found broad applications across diverse fields, including medicine, food industry, and biotechnology. This study addresses their microbiological safety, a critical factor given the propensity of microorganisms to colonize commonly used nanomaterials. Ensuring microbiological safety can be achieved by either functionalizing nanofibers with antimicrobial agents or by modifying their morphology. Previous studies have indicated that fiber diameter and surface density markedly influence interactions between nanomaterials and microbial cells. In this work, we investigated the effect of fiber diameter on biofilm formation and bacterial cell retention using two polycaprolactone (PCL) nanofibrous materials, PCL45 and PCL80. Four model bacterial strains—Escherichia coli (ATCC 25922 and 8739) and Staphylococcus aureus (ATCC 25923 and 6538) —were selected as representative opportunistic pathogens of relevance to biomedical, food, and biotechnological contexts. Compared to polystyrene (used as a control), the thinner-fibered PCL exhibited reduced biofilm formation. Fiber diameter did not significantly affect biofilm formation for three strains (p > 0.05), but did influence one E. coli strain (p < 0.05). Additionally, fiber morphology affected the structure and spatial distribution of biofilms. Bacterial retention assays further demonstrated that fiber diameter significantly influenced cell retention (p < 0.01), with PCL45 showing generally higher retention. Notably, PCL45 fully retained Staphylococcus cells, whereas E. coli was retained to a lesser extent. These findings support the hypothesis that fiber morphology modulates microbial interactions and underscore the necessity for further in-depth investigation.

The research was supported by Czech Science Foundation Grant No. 23-05154S.

Transport and reactivity mapping of pharmaceuticals in soil and aquatic environments is vitally important for environmental safety. Pharmaceuticals can interact with organic matter which can result in their partial immobilization and suppression of their migration, bioavailability, and toxicity. Humic substances as important constituents of natural organic matter were used for the preparation of hydrogel medium for the monitoring of drug transport accompanied by the interactions between humic substances and pharmaceuticals. Humic hydrogel can be considered as a model system of soil with characteristic content of organic matter. Diclofenac was chosen for the investigation of their transport in hydrogels as a representative of widely used non-steroidal anti-inflammatory drugs. The method of instantaneous planar source was used for the transport and reactivity mapping of diclofenac in humic hydrogel. The method is based on a small defined amount of diffusing substance placed on the circular surface of cylinder-shaped hydrogel (placed in glass tube to achieve one-dimensional diffusion). The method can provide diffusion parameters as effective diffusion coefficients characterizing drug transport affected by interactions with active sites of humic substances and apparent equilibrium constant between immobilized and free movable drug particles. Diffusion study was complemented by adsorption and desorption experiments to compare traditional and our novel approaches. The mobility of diclofenac in humic hydrogel as well as its immobilization ability and bioavailability of pharmaceutical are discussed.