Seznam abstraktů 2025: SEKCE C - BIONANOTECHNOLOGIE, NANOMATERIÁLY PRO MEDICÍNU

Carbon nano-onions (CNOs)—multi-layered fullerenes composed of concentric sp²-hybridized carbon shells—are emerging as promising nanocarriers for targeted drug delivery due to their cellular uptake, low toxicity, and high surface functionalization capacity.
Our group has developed a reliable method for synthesizing pure, monodisperse CNOs and functionalizing their surfaces with receptor-targeting and imaging units. These modified CNOs demonstrate high photostability in aqueous media and selective uptake by cancer cells without significant cytotoxicity. We employed supramolecular functionalization using a hyaluronic acid-phospholipid (HA-DMPE) conjugate to target CD44-overexpressing cancer cells and improve nanocarrier solubility.
HA-DMPE-functionalized CNOs showed enhanced cellular uptake and viability in CD44+ human breast cancer cells compared to CD44− ovarian cancer cells. In vivo zebrafish studies confirmed strong biocompatibility throughout development. We further loaded the CNOs with gemcitabine-derived prodrugs, achieving potent cytotoxic effects against pancreatic adenocarcinoma cells.
In parallel, doped BN-CNOs were functionalized with HA-DMPE for pH-triggered delivery of doxorubicin (DOX). This system showed superior uptake and anticancer activity in MDA-MB-231, MDA-MB-468, and MCF-7 breast cancer cells compared to free DOX and Caelyx®, and significantly reduced cardiotoxicity in AC16 human cardiomyocytes.
These results demonstrate the potential of CNO-based systems as safe, effective platforms for targeted cancer therapy and highlight their promise in advancing nanomedicine.

The physical principles of crosslinking water-soluble polymers offer innovative pathways to creating hydrogels. Overall, hydrogels have very specific properties, that closely mimic the mechanical properties of native tissues. Moreover, the high-water content of hydrogels supports better nutrient supply, metabolites’ disposal and is also beneficial for drug delivery systems. Unlike chemical crosslinking, physical crosslinking methods avoid cytotoxic reagents, enhancing biocompatibility and applicability for tissue engineering applications. It can be stated, that by physical crosslinking we produce highly pure scaffolds without any additional undesired chemicals.
The polymers polyvinylalcohol (PVA) and gelatin (GEL) were chosen as representatives of water-soluble natural (GEL) and synthetic (PVA) polymers for these experiments. The polymers were electrospun by NanospiderTM and further irradiated by β-electrons (Microtron MT25, NPI CAS, doses of 50 and 100 kGy). The morphology of the fibers was evaluated prior and after irradiation by the scanning electron microcopy, followed by the stereological evaluation of the fiber diameter. The irradiated fibrous materials were further examined in the means of water-solubility and cytotoxicity according to the ISO 10993.
This research contributes to the advancement of tissue engineering in the field of hydrogels, a field poised to revolutionize medical treatments by enabling the development of sustainable, biocompatible tissue replacements.
ACKNOWLEDGEMENTS: This research is funded by the project SGS-2025-4519 of Technical University of Liberec.

In recent years, the incidence of postoperative infections has been increasing due to the use of artificial implants. Bacterial resistance is a challenging limitation in the treatment of infections. Thus, the development of antimicrobial implants in orthopedic with proven antimicrobial activity are developed in present research. The antibacterial activity was achieved by a novel conjugate (Silver@AMP) of Silver and antimicrobial peptides (AMP). At first green synthesis approach used to develop the Silver nanoparticles. Then, AMP were obtained from Bellamya bengalensis, a fresh water snail. Subsequently, their conjugates were prepared. The physicochemical characterization of the nanocomposites were characterize by UV-Visible spectroscopy, Zetasizer. TEM (HITACHI H-800) Fourier transmission electron microscopy (FTIR) etc. Antimicrobial assessment of MXene@AMP composite was performed by Resazurin microtitre assay method (REMA). Secondly, three implants (pure titanium, stainless steel and polyethylene) were selected to grow the biofilm on their surfaces. The coating was analyzed under confocal microscopy.

Over the past decades, the escalating problem of antimicrobial resistance (AMR) has kept challenging the clinical treatments for infectious diseases. The evolution of antimicrobial-resistant bacteria has limited the antibiotic options and increased the complexity in treating the infections. Nowadays, one of the main strategies in fighting AMR is to develop alternative treatments to antibiotics preventing resistance. Reactive oxygen species (ROS) based treatments, as one of the most promising antibiotic-free strategies, have gained increasing attention in the field. ROS, a class of highly reactive molecules, ideally can induce direct damage to the pathogens through lipid, protein, and/or DNA oxidation. Within this framework, nanomaterials that present catalytic activities, like naturally occurring enzymes that can mediate ROS generation and scavenging, are being explored. Here we reported three different nanoyzmes (Vanadium Carbide MXenes, Molybdenum Boride MBenes, and Borophene) synthesised with green chemistry that can mimic Peroxidase-like and/or Catalase-like activities. These enzyme-mimicking activities show their potential to be utilised for antibacterial and/or anti-inflammatory applications. Due to the high light-responsive property of nanozymes, the light enhancement can help to increase the effectiveness of nanozymes while also providing a more controllable dual- or multi-enzyme mimic activities to overcome potential resistance development. For this study, we also combined nanozymes with microneedles, aiming to provide a more precise transdermal drug delivery to treat skin subdermal infections where the antimicrobial-resistant drug usually effect. In this project, we introduced light-tunable nanozyme-based microneedles to provide a transdermal treatment that can fight the bacteria while controlling the inflammation.

The biological properties of 2D nanomaterials MXenes are strongly influenced by flake size, surface functionalization, and concentration. Titanium carbide MXene (Ti₃C₂Tₓ) has high photothermal conversion and good stability in biological solutions, making it a new perspective option for biomedical applications such as photothermal therapy (PTT). Melanoma is a highly aggressive metastatic tumor that requires very precisely targeted treatment. Melanoma is a highly aggressive metastatic tumor that requires very precisely targeted treatment. For this purpose, MXene flakes as a photosensitizer can be essential.
Our study systematically evaluates the relationship between MXene flake size and biological effects using a multi-assay approach for investigating cell viability, apoptosis, and proliferation, genotoxicity, and immunomodulatory potential. The study compared dose dependence (6.25, 25, and 100 µg/mL) in different coincubation times (4h, 24h, 72h).
Ti₃C₂Tₓ flakes modified with polydopamine and targeted antibodies demonstrate exceptional photothermal efficiency under NIR-I laser (808nm) irradiation. Testing various irradiation modes from 2 to 4 W and from 10 to 50 Hz, during 5 or 10 min, reveals a direct correlation between temperature increase and MXene concentration, with 50 µg/mL achieving 47.8°C - sufficient for selective melanoma cell ablation. Targeted antibody functionalization enhances specificity, minimizing off-target effects.
These findings elucidate the structure-function relationships critical for optimizing MXene-based platforms, highlighting their potential for precise, safe, and effective PTT in oncology.
ACKNOWLEDGEMENTS: The Latvian Council of Science (LCS) Project (Grant lzp-2024/1-0135).

Electrospun poly(ε-caprolactone) (PCL) nanofibers are promising materials for biomedical applications due to their biocompatibility and biodegradability. PCL is a semicrystalline polymer, and its functional properties are strongly influenced by its crystalline-amorphous morphology. While the crystalline and amorphous domains are commonly distinguished, recent studies on multiphase polymers suggest that the amorphous region can be further subdivided into rigid and mobile fractions. The so-called rigid amorphous phase (RAP) is typically located near the crystallite boundaries, where chain mobility is significantly restricted, while the mobile amorphous phase (MAP) retains high segmental mobility. In this study, we applied modulated differential scanning calorimetry (MDSC) to quantify the crystalline, RAP, and MAP fractions in electrospun PCL nanofibers. Although the three-phase model is known in filled polymers, its application to nanofibrous systems has not been explored so far. Nanofibers were prepared from 16 wt% PCL solution in chloroform:ethanol (8:2 wt), and multiple MDSC runs confirmed the reproducibility of phase separation. The crystalline fraction appeared as the most dominant phase, while both amorphous fractions were also clearly distinguishable. The phase proportions exhibited only minor variation across repeated measurements, supporting the robustness and reproducibility of the method. Since degradation behavior depends strongly on amorphous mobility, this approach may aid in designing resorbable nanofibrous scaffolds with tailored properties.

The traditional focus of biosensors is detection of glucose in diabetic patients. The single use devices are being replaced by continuously measuring wearable systems providing improved performance and user comfort. Our experience from monitoring glucose in sweat will be reported. However, biosensors are developed for many other analytes. One of the drivers is the detection of very low concentrations of biomarkers. In many critical situations, even a few molecules of toxins can be harmful, individual pathogenic microbes initiate infectious disease, and traces of cancer markers indicate the beginning of malignant transformation. From the suitable approaches, single-molecule immunochemical sensors and assays provide the detection of individual analyte molecules reaching the ultimate sensitivity in analytical chemistry [1]. Immunosensors are being developed to enhance the sensing capabilities, lower limits of detection and provide point-of-care mode of use with short analysis times. The promising approaches recently initiated in our laboratory include digital affinity sensing - single-molecule assays (or better single-analyte to include also viruses, bacteria and cells), combination of optical and electrochemical transduction, and inorganic nanocrystals for either luminescent labelling (quantum dots, photon up-conversion nanoparticles) or catalytic (Prussian blue nanoparticles) signal enhancement [2]. Furthermore, advanced nanotools based on scanning probe microscopies allowed us to touch and interface individual cells using nanomechanical transducers, in combination with microelectrode arrays and fluorescence [3]. This provides detailed information on the physiological state of patients-derived cells, allows to model disease progress at the cellular level and optimize personalized medication. In conclusion, the combination of biosensors with new tools and materials and tools resulting from nanobiotechnology studies allowed this field to direct new horizons.
REFERENCES: [1] Farka, Z; Mickert, MJ; Pastucha, M; Mikušová, Z; Skládal, P; Gorris, HH. Advances in optical single-molecule detection: en route to supersensitive bioaffinity assays. Angew. Chem. Int. Ed. 59 (2020) 10746; [2] Farka, Z.; Juřík, T.; Kovář, D.; Trnková, L.; Skládal, P. Nanoparticle-based immunochemical biosensors and assays: Recent advances and challenges. Chem. Rev. 117 (2017), 9973; [3] Caluori, G.; Přibyl, J.; Pešl, M.; Jelínková, S.; Rotrekl, V.; Skládal, P.; Raiteri, R. Non-invasive electromechanical cell-based biosensors for improved investigation of 3D cardiac models. Biosens. Bioelectron. 124 (2019) 129.

Accurate mapping of pH at the nanoscale with high spatial and temporal resolution is essential for understanding many physiological and pathological processes. However, current fluorescence lifetime-based pH nanosensors are often challenging to synthesize and are limited by poor biocompatibility, a narrow pH range, and stability issues. In this work, we present a simple one-step synthesis of biocompatible, water-dispersible carbon dots (CDs) from Rhodamine B, yielding a robust pH nanosensor with excellent performance. These CDs exhibit a stable, pseudo-linear fluorescence lifetime response across an exceptionally broad pH range (1-11), enabled by pH-dependent modulation of their electronic states. Using fluorescence lifetime imaging microscopy (FLIM), we demonstrate their intracellular localization to lysosomes in human skin fibroblasts and the ability to quantitatively track inhibitor-induced pH changes. This approach offers a powerful platform for real-time, calibration-free monitoring of pH dynamics in live cells, with broad potential applications in biomedical and cellular research.

Memristors are metal/insulator/metal (MIM) devices capable of retaining and recalling their resistance through an applied electric field, allowing them to remember past memory states. This resistive switching behavior can arise from oxygen vacancy migration or interfacial effects, such as Schottky barrier modulation. TiO₂ is a common material for MIM architectures due to its wide bandgap, high dielectric constant, and natural tendency for oxygen vacancy formation. In particular, anodically grown TiO₂ layers offer self-rectifying properties, which help suppress sneak-path currents in crossbar arrays, making them attractive for sensing applications. Besides memory storage, memristors are gaining traction in neuromorphic computing, as their conductance alters in response to electrical stimuli, which closely resembles biological synaptic plasticity. This behavior enables them to process and store information analogous to the synapses in the brain. For this reason, dopamine, a key neuromodulator in biological systems, plays a crucial role in strengthening or weakening synaptic connections during learning processes.
In this work, a Ti/TiO₂/Pt memristive sensor was developed for the selective detection of dopamine.The device was fabricated by sputtering a Ti layer as the bottom electrode (BE), followed by anodization to form the active insulating TiO₂ layer (AIL). To complete the MIM structure a Pt top electrode (TE) was sputtered lastly. Various concentrations of dopamine solution were drop-cast directly onto the exposed oxide surface. During the electrical measurements, the BE was biased while the TE was grounded. The recorded I-U sweeps showed a dopamine concentration-dependent resistance increase, suggesting that dopamine adsorption or partial charge transfer affects the conductive pathways within the oxide layer, responsible for the resistive switching behavior. The results highlight the potential of the memsensor for neurotransmitter detection and suggest future applications in neuromorphic computing. Further surface and structural characterization are ongoing to interpret the sensing mechanism and assess the device’s stability.

Lateral flow immunoassays (LFIAs) are widely used analytical tools that offer straightforward and cost-effective detection of clinical biomarkers. However, conventional LFIAs utilizing gold nanoparticle-based labels are often limited to qualitative results and may lack the sensitivity to detect low-abundance analytes. One strategy to overcome these limitations is to replace the labels with advanced nanomaterials. Recently, labels based on photon-upconversion nanoparticles (UCNPs) have emerged as particularly promising due to their anti-Stokes emission, reducing background interference from naturally occurring fluorophores.
In this study, we developed and optimized an LFIA using a piezo-driven low-volume dispenser for precise antibody deposition. Subsequently, we evaluated the performance of five different nanoparticle-based labels: gold nanoparticles, gold nanoshells, and three types of UCNPs varying in size, dopant composition, and surface chemistry. The best-performing labels, gold nanoshells and polyacrylic acid-coated UCNPs, were then used to detect human serum albumin (HSA) and prostate-specific antigen (PSA) in spiked urine and serum, respectively.
For HSA analysis in urine, the developed LFIA achieved a limit of detection (LOD) of 150 pg/mL using gold nanoshells and 63 pg/mL with polyacrylic acid-coated UCNPs. For PSA detection in serum, the LODs were 39 and 34 pg/mL for gold nanoshells and UCNPs, respectively. Nevertheless, PSA detection using UCNPs exhibited a significantly stronger correlation with the reference values (82-119% recovery), as gold nanoshells tended to aggregate in serum. These findings highlight the potential of UCNP-based labels to enhance LFIA sensitivity and enable precise quantitation of analytes in clinical diagnostics.

Cancer remains a leading cause of global mortality, with Prostate Cancer (PCa) ranking as the fourth most common cancer in men. Early diagnosis is one of the most important factors in determining its prognosis, and it is feasible especially for its possible recurrences. Sensitive detection of tumour-specific biomarkers, especially in liquid biopsies or directly in the bloodstream, has the potential to improve significantly our diagnostic capability. I will discuss about triggerable nanostructures based on oligonucleotides / (ultrasmall) gold nanoparticles (NPs) architectures, which selectively disassemble in the presence of the biomarker of interest thanks to an aptamer forming a section of one of the oligonucleotides, partially paired to a complementary sequence. Their optimization are based also on in-silico determination of the aptamer interactions with the protein of interest. We demonstrated this scheme for the case of Prostate Specific Membrane Antigen (PSMA), also derived from exosomes, and of Prostate Specific Antigen (PSA). We tested the disassembly of the systems by diameter and count rate measurements in dynamic light scattering (DLS), and by inspection of its plasmon resonance shift. We found appreciable differences upon addition of the recognized biomarker down to the sub-picomolar range in the first case and to the femtomolar range in the second one. I will moreover discuss the analysis of the DLS data, the electromagnetic coupling amongst the NPs, and most importantly the performed experiments and the further requirements for in-vivo diagnostic applications especially of the PSA-sensitive system, based on renal-excretable 4-nm ultrasmall NPs.

Single-atom nanomaterials (SAMs) represent a new frontier in nanobiotechnology, offering atomic precision in catalytic and biomedical functionalities. In recent years, they have gained increasing attention along three rapidly expanding research axes in biomedicine: anticancer therapy, antibacterial/antimicrobial applications, and modulation of redox homeostasis in inflammatory or neurodegenerative conditions. Despite this progress, a fundamental understanding of how the atomic structure of SAMs governs biological outcomes remains largely elusive. In our work, we present a comprehensive investigation into the structure-activity relationships of atomically dispersed metals anchored on nitrogen-doped graphene acid (NGA), a highly tunable 2D platform. By controlling metal identity and coordination at the atomic level, our aim is to mechanistically dissect cellular responses—ranging from immune activation to cancer cell death and bacterial inhibition. Furthermore, given the rapid rise of SAMs in catalytic and biomedical fields, we emphasize the need for comprehensive evaluation of their biological interactions and safety profiles. Together, this work outlines a framework for guiding the rational and safe-by-design development of SAMs for future biomedical use.
ACKNOWLEDGMENTS: The work is supported from European Regional Development Fund - Project “Excellence in Regenerative Medicine” (CZ.02.01.01/00/22_008/0004562) and with the financial support of the European Union under the REFRESH - Research Excellence For Region Sustainability and High-tech Industries project number CZ.10.03.01/00/22_003/0000048 via the Operational Programme Just Transition.

Understanding the toxicity of nanoparticles (NPs) is essential for developing safer-by-design advanced materials. Toxicity testing typically begins with cytotoxicity assays, followed by assessments of oxidative stress, genotoxicity, and inflammation; each requiring careful consideration of potential assay interference. High-throughput methods, including reporter cell lines, can offer efficient screening. We employed the ToxTracker assay, a panel of GFP-tagged reporters for key stress pathways, to evaluate the (geno)toxicity of 33 metal and metal oxide NPs, as well as quantum dots. Most NPs activated oxidative stress reporters, while fewer triggered DNA damage responses. While ToxTracker enables rapid profiling of reactive NPs, it does not capture secondary genotoxicity driven by inflammation. Co-culture models can be a solution for such assessments. Additionally, conventional submerged exposure may not reflect physiological conditions of the lung. Air-liquid interface (ALI) exposure offers a more relevant model but remains technically challenging. For long-term endpoints such as malignant transformation, extended exposure is required, followed by transformation assays to assess phenotypic changes like loss of contact inhibition and anchorage-independent growth. Omics approaches including transcriptomics, proteomics, and metabolomics provide broad mechanistic insights but generate complex datasets that may pose analytical challenges. Recently, phenomics has emerged as a complementary approach, using Cell Painting to capture high-dimensional morphological profiles via fluorescent staining of cellular compartments. This image-based method complements molecular assays and may advance nanosafety assessment.

The biological mechanisms in wounded skin after the application of mesenchymal stem cells (MSCs) and nanoparticles (NPs) (Ag, ZnO), either alone or combined, were studied in mice, with the aim of determining the optimal approach to accelerate the healing process. This combined treatment should be associated with the production of molecules supporting the healing process and antimicrobial activity. The samples were collected seven days after injury. When compared with untreated wounded mice (controls), the combined (MSCs+NPs) treatment induced the expression of Sprr2b, a gene encoding small proline-rich protein 2B, involved in keratinocyte differentiation, the response to tissue injury, and inflammation. Pathways associated with keratinocyte differentiation were also affected. Ag NP treatment (alone or combined) modulated DNA methylation changes in genes involved in desmosome organization. The percentage of activated regulatory macrophages at the wound site was increased by MSC-alone and Ag-alone treatments, while the production of nitric oxide, an inflammatory marker, by stimulated macrophages was decreased by application of both MSC/Ag alone and MSCs+Ag. Ag induced the expression of Col1, encoding collagen-1, at the injury site. The results of the MSC and NP treatment of skin wounds (alone or combined) suggest an induction of processes accelerating the proliferative phase of healing. Thus, MSC-NP interactions are a key factor affecting global mRNA expression changes in the wound. Supported by grant No. 21-17720S from the Czech Science Foundation. Data processing was supported by the Strategy AV21 program: AI: Artificial Intelligence for Science and Society.

Abstract: Nanoplastics are an emerging environmental concern, with an increasing evidence highlighting their potential impact on neurodevelopmental impairments such as Autism Spectrum Disorder (ASD). The purpose of this study was to evaluate the impact of Polystyrene (PS) nanoplastics with different surface charges—positive and negative—on autism-like behavior, using zebrafish (Danio rerio) larvae, as a model for studying neurodevelopmental disorders. Zebrafish larvae were exposed to PS nanoplastics at two different concentrations of 100 µg/L and 500 µg/L. Autism-related behaviors were analyzed through basic locomotor activity and sensory processing assessments, considering the travelled distance and epileptic-like motor pattern in light/dark transition. The results revealed a significant concentration-dependent reduction in locomotor activity, evaluated by the distance travelled in light/dark transition. Notably, at the higher concentration (500 µg/L), negatively charged PS nanoplastics induced greater behavioral dysregulation, including erratic movements and hyperactivity under sensory stimulation (light-dark transitions), suggesting sensory processing impairments. PS nanoplastics uptake analysis indicated a significant higher uptake at lower concentration for both positive and negative charges. Moreover, at the same concentration, negatively charged nanoplastics exhibited significantly higher internalization for both experimental concentrations, particularly at 100 µg/L. These findings underscore the role of nanoplastics’ physicochemical properties in modulating neurobehavioral outcomes and raise concern over their potential contribution to neurodevelopmental disorders. Further studies are warranted to explore long-term effects and underlying mechanisms.
ACKNOWLEDGEMENT: This paper received support from the project “FIS-2023-00527- CUP C53C24001400001” funded by department of chamical sciences, university of Padova, Italy.

Silver nanoparticles (AgNPs) have been extensively investigated for their biostimulatory or toxic effects on microalgae. However, the influence of the inoculum’s developmental stage on astaxanthin biosynthesis in the microalga Haematococcus pluvialis remains largely unexplored. This study aimed to assess the effects of AgNPs on biomass and astaxanthin production in Haematococcus pluvialis by comparing cultures initiated with two distinct inoculum types: green vegetative cells and aplanospores. Experimental cultures were exposed to silver nanoparticles of 40 and 60 nm, each applied at five concentrations (from 0.01 to 1.0 mg/L). Biomass and astaxanthin content were quantified to evaluate the metabolic responses induced by AgNPs exposure. Both inoculum types exhibited a similar response profile: exposure to 40 nm AgNPs did not induce astaxanthin synthesis at any tested concentration. When astaxanthin was determined in the aplanospore stage, the green-cell inoculum showed inhibited accumulation at all concentrations, with over a 20% reduction, while the aplanospore inoculum maintained control levels. For 60 nm AgNPs, final astaxanthin content in Haematococcus pluvialis cultures with green motile cell inoculum increased by 8.7-13.3%, mainly at higher concentrations. With the aplanospore inoculum, red-stage astaxanthin increased by 50-80% at all concentrations. A slight reduction in biomass was observed in green-cell cultures treated with 40 nm AgNPs, while aplanospore-based cultures maintained more stable biomass growth. The results underline the critical role of the inoculum’s developmental stage in modulating the metabolic response of Haematococcus pluvialis to AgNPs and provide a foundation for optimizing astaxanthin yield through nanoparticle-assisted cultivation strategies. This research was supported by a grant of NARD, project 24.80012.7007.08 SE.

Gold nanoparticles exhibit unique optical and electronic properties, which can be utilised in a variety of applications, from electronics to nano-bio-medicine. Changes in precursor concentrations tune size, shape, surface chemistry and charge of the resulting nanostructures. Chemical synthesis of nanoparticles often relies on the use of toxic chemicals as reducing and stabilising agents. On the contrary, green synthesis is a chemical method that uses safe and often cheap chemicals. Nowadays, there is an urgent demand for sustainability and environmental friendliness of synthetic protocols, especially in the field of bio-applications of nanomaterials. It is known for many years that amino acids can play the key role as both, reducing and stabilising agents in gold nanoparticle formation; moreover, they are biocompatible and biodegradable. Nevertheless, synthetic parameters still require optimization such as for instance: concentration changes and mutual ratios of reactants, physical and chemical conditions of the synthesis.
In this work we synthesised gold nanoparticles (AuNPs) via four different aromatic amino acids (Tyr, Trp, Phe. and His), under several different temperatures. AuNPs were then characterised by means of UV-Vis absorption spectroscopy, DLS (dynamic light scattering), ELS (electrophoretic light scattering, TEM (transmissive electron microscopy) and FT-IR (Fourier transform infrared spectroscopy) . The as-prepared AuNPs possessed LSPR (localised surface plasmon resonance( peak located at ~520 - 540 nm and manifested themselves by sizes of 10 - 30 nm in diameter. The dialysed samples were tested and their cytotoxic effect evaluated on MCF-7 and BJ cell lines (Calcein-AM fluorescence assay). Significant differences in cell viability were found in AuNPs synthesised by tyrosine and phenylalanine (Tyr@AuNPs and Phe@AuNPs): Phe@AuNPs exhibited cytotoxic effect in both cell lines, whereas Tyr@AuNPs were selectively cytotoxic only to MCF-7. We presume that the different oxidation products of Tyr and Phe, resulting from AuNPs formation, serving as AuNPs capping agents, are causing the difference in cytotoxicity. However, further research must be conducted.
The authors acknowledge the financial support by Internal Grant Agency (project no. IGA_PrF_2025_007).

Magnetic resonance imaging (MRI) is a powerful tool for studying nanoparticle biodistribution in vivo, but conventional approaches usually rely on qualitative assessment from T1-, T2-, or T2*-weighted images. These methods provide only indirect estimates of nanoparticle concentration and are sensitive to motion artifacts. We present a new quantitative MRI methodology for evaluating biodistribution of gadolinium-labeled nanoparticles in small animals. The method is based on T1 mapping and designed to be robust against respiratory and potentially also cardiac motion, ensuring reliable longitudinal measurements of nanoparticle concentrations.
The approach was tested in six tumor-bearing mice (BALB/c, 4T1 tumor), each imaged at five fixed time points within 48 hours after intravenous administration of gadolinium-labeled lipid nanoparticles carrying ellipticine, or, as a reference, the standard contrast agent Gadovist. Our results demonstrate reproducible T1 quantification in the tumor, kidney, liver, and spleen, enabling direct and quantitative analysis of nanoparticle accumulation and clearance over time.
This methodology represents a robust, noninvasive strategy for assessing nanoparticle biodistribution and may facilitate the preclinical development of novel nanomedicine therapies.

Nanofibrous materials have potential in medical applications. The application of nanofibrous yarns as medical fibers, involving sutures, has been suggested to enhance the quality of the repair. However, due to a lack of robustness of the current fabrication methods, continuous nanofibrous filaments cannot be manufactured and scaled up in industrial settings and are not currently available for clinical use. To solve this problem, we have developed an effective method that enables the manufacture of electrospun yarns of two classes (100% nanofibrous yarns and composite yarns with nanofibrous shells), with the potential to be applied as surgical sutures. Presentation of production technologies via videos, process and material parameters of nanofibre yarn production by AC electrospinning, including possible modifications and post-process treatments such as braiding or surface treatment of nanofibres in yarns, represents the versatility of these materials, mainly by detailed scanning electron microscope images. In particular, the focus is on applications as surgical suture threads, and related to this, the basic properties and evaluation procedures of these nanofibrous threads or composite threads with nanofibers are presented.

Acne vulgaris is a serious dermatological disease affecting a significant part of the population. Currently, available therapeutics are effective only at high concentrations, which has a negative environmental and economic impact. In particular, ZnO nanoparticles (NPs) have a great potential in various biomedical applications due to their specific properties and antibacterial/antiviral aktivity [1,2].
Electrospinning is a well-known technique for the nanofiber synthesis from a solution using high electrostatic field. However, this technique still has some shortcomings, such as a low production rate and requires a high voltage. Centrifugal spinning works only on centrifugal force, which is robust in terms of yield, and thus eliminates the above-mentioned shortcomings [3,4]. The fibers based on gums blended with other polymers can be shaped and modified according to the targeted application. Recently, new approaches to the use of polymeric fibers have also shown potential for cosmetic and dermatological applications. In general, different types of creams, hydrogels and films are often being limited by their application, e.g. due to easy contamination over time and prevention of skin ventilation [5]. In contrast, fibrous materials possess unique characteristics, including high porosity, a large specific surface area, and good breathability, making them ideal carriers for cosmetic and dermatologic application. Combining fibers with ZnO NPs creates a synergistic effect that holds great promise for the effective treatment of Acne vulgaris [6].
In this study, biomedically approved ZnO NPs with distinct diameter were used as the active therapeutic modality to treat acne-causing pathogens. For the first time, we show the utilization of ZnO NPs that were evenly distributed within centrifugally spun fiber carriers. Upon application on the skin, ZnO NPs can sustainably release and have profound antibacterial activity at lower therapeutic concentrations. Fibers were made using innovative centrifugal spinning procedure from natural polymers - gum arabic and pullulan - that are known for their biocompatibility. Different amount of ZnO NPs (from 0.03 to 4.5 wt.% related to the dry mass) was added into the spinning polymer solution, either in a form of a dry powder or as a dispersion containing NPs and isopropyl myristate. The resulting fibers were subsequently characterized for morphology and presence of ZnO NPs by Scanning Electron Microscopy and Energy-Dispersive X-ray fluorescence spectrometry. The materials were thoroughly assessed for their antibacterial activity against Cutibacterium acnes and Staphylococcus epidermidis, which are major opportunistic pathogens causing acne. The combination of two types of nanomaterials, namely active nanoparticles and fiber carriers, proved to be very promising and bear a great potential for the treatment of these diseases [6,7].
REFERENCES: [1] R. Balkrishnan et al., Predictors of healthcare outcomes and costs related to medication use in patients with acne in the United States, Clin. Ther. 77(2006), 251-255; [2] A. Sirelkhatim et al., Review on zinc oxide nanoparticles: Antibacterial activity and toxicity mechanism, Nano-Micro Lett. 7(2015), 219-242; [3] M. Rihova et al., Water-born 3D nanofiber mats using cost-effective centrifugal spinning: comparison with electrospinning process: A complex study, J. Appl Polym Sci. 168 2021), e49975; [4] S. Padron et al., Experimental study of nanofiber production through forcespinning, J. Appl. Phys., 113(2013), 024318; [5] M. Rihova et al., The centrifugal spinning of vitamin doped natural gum fibers for skin regeneration, Carbohydr. Polym. 294(2022), 119792; [6] M. Rihova et al., Biopolymeric fibers prepared by centrifugal spinning blended with ZnO nanoparticles for the treatment of Acne vulgaris, Appl. Mater. 37(2024), 102151; [7] M. Rihova et al., Centrifugally spun and ZnO-infiltrated PVA fibers with antibacterial activity for treatment of Acne vulgaris, J. Control. Release 383, 113777.

TiO2 surfaces are in general recognized as excellent biocompatible materials, owing to their low cytotoxicity, high stability, antibacterial properties, and wetting ability. Among various TiO2 nanostructured surfaces that show very good cell interactions (various cell types) and osseointegration, self-organized TiO2 nanotube (TNT) layers, grown by anodization of Ti, have emerged as extremely suitable substrates. Numerous papers showed also that anodization is a very viable tool for nanostructuring of various biomedical alloys, including frequently used TiAlV [1,2]. A pioneering work demonstrated that TNT layers with diameter of 15 nm are the most suitable for the growth of various cells [3]. In this presentation, we will demonstrate that ultrathin coatings of TiO2 [1,2,4,5], ZrO2, and V2O5 [6] can significantly increase the cell proliferation and adhesion on various TiO2 surfaces, including anodized ones. Last, but not least, black form of TNT layers (i.e. with significant content of Ti3+ states) was investigated for cell proliferation in comparison to classical TNT layers [7].
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[6] K. Baishya, J. Bacova, B. A. Chimali, J. Capek, J. Michalicka, G. Gautier, B. Le Borgne, T. Rousar, J. M Macak. ACS Appl. Mater. Interfaces, 17, 1, 739-749, 2025.
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In this study, we report a biosynthesis of ZnO nanoparticles using a leaf extract from Reynoutria bohemica, an invasive plant species abundant in Central Europe. The phytochemicals present in the extract served as reducing and stabilizing agents, enabling the formation of ZnO particles upon thermal treatment. Optimization of reaction conditions revealed that calcination at ≥300 °C is essential for the formation of phase-pure wurtzite-structured ZnO. The resulting particles exhibited a pyramidal particles decorated with nanocrystallites. The sizes of the prepared nanoparticles reached hydrodynamic diameters ranging from 48 to 128 nm depending on the calcination temperature.
Compared to conventionally synthesized ZnO, the biosynthesized materials showed a pronounced red-shift in the optical absorption edge (∼540 nm), along with intense green photoluminescence centered around 595 nm. These features are attributed to the presence of oxygen vacancies within the ZnO lattice, which was supported by density functional theory (DFT) calculations. Moreover, the isoelectric points of biosynthesized ZnO were significantly shifted towards more acidic values (pH 2.7-4.0), suggesting altered surface chemistry and enhanced colloidal stability.
This work highlights the potential of invasive biomass as a sustainable precursor for advanced oxide materials and underlines the role of defect engineering in tuning the functional properties of ZnO.
ACKNOWLEDGEMENT: This work was financially supported by the European Union under the LERCO project number CZ.10.03.01/00/22_003/0000003 via the Operational Programme Just Transition. MŠMT ČR 8X23021 Multifunkční hybridy na bázi ZnO pro sanaci odpadních vod, ČR - SR - Srbsko projektu LERCO Evropské unie CZ.10.03.01/00/22_003/0000003.