Publications by authors named "Pavlina Modlitbova"

This pilot study investigated the metabolic responses of five selected bacteria to physiological stress. Surface-enhanced Raman spectroscopy was used to analyze spectral changes associated with the release of adenine, a key metabolite indicative of stress conditions. Laboratory-synthesized spherical silver and gold nanoparticles, which remained stable over an extended period, were employed as enhanced surfaces.

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There is an increasing tendency to replace conventional agricultural plastic mulching films with biodegradable alternatives. However, while the latter biodegrade well under controlled conditions (e.g.

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Contamination of the environment with toxic metals such as cadmium or lead is a worldwide issue. The accumulator of metals Cannabis sativa L. has potential to be utilized in phytoremediation, which is an environmentally friendly way of soil decontamination.

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Laser-induced breakdown spectroscopy is often combined with a multivariate black box model-such as support vector machines (SVMs)-to obtain desirable quantitative or qualitative results. This approach carries obvious risks when practiced in high-stakes applications. Moreover, the lack of understanding of a black-box model limits the user's ability to fine-tune the model.

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Immunohistochemistry (IHC) and immunocytochemistry (ICC) are widely used to identify cancerous cells within tissues and cell cultures. Even though the optical microscopy evaluation is considered the gold standard, the limited range of useful labels and narrow multiplexing capabilities create an imminent need for alternative readout techniques. Laser-induced breakdown spectroscopy (LIBS) enables large-scale multi-elemental analysis of the surface of biological samples, e.

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The main purpose of this work is to thoroughly describe the implementation protocol of laser-induced breakdown spectroscopy (LIBS) method in the plant analysis. Numerous feasibility studies and recent progress in instrumentation and trends in chemical analysis make LIBS an established method in plant bioimaging. In this work, we present an easy and straightforward phytotoxicity case study with a focus on LIBS method.

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The improving performance of the laser-induced breakdown spectroscopy (LIBS) triggered its utilization in the challenging topic of soft tissue analysis. Alterations of elemental content within soft tissues are commonly assessed and provide further insights in biological research. However, the laser ablation of soft tissues is a complex issue and demands a priori optimization, which is not straightforward in respect to a typical LIBS experiment.

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The implementation of quantum dots in analytical chemistry has already advanced from basic research activities to routine applications of commercially available fluorescent agents present in sophisticated assays kits. Nevertheless, a further development of new preparation and characterization methods of nanoparticles is still required to increase the sensitivity of analytical methods substantially. Thus, in many bioanalytical applications, important molecules such as DNA, proteins, and antibodies are routinely conjugated with fluorescent tags to reach even the absolute sensitivity, that is, the capability to detect a single molecule in complex matrices.

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In this study, a model crop plant white mustard (Sinapis alba L.) was treated with an aqueous dispersion of silica-coated CdTe quantum dots (CdTe/SiO QDs) in a 72-h short-term toxicity test. The toxicity was established via measurements of (i) the root length and (ii) the chlorophyll fluorescence.

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Laser-induced breakdown spectroscopy (LIBS) was examined as a novel method for readout of microtiter plate immunoassays involving nanoparticles (NP). The so-called Tag-LIBS technique is a sensitive method for the detection of specific biomarkers. It was applied to the determination of NP labels using nanosecond ablation sampling.

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In this study, radish (Raphanus sativus L.) and common duckweed (Lemna minor L.) were treated with an aqueous dispersion of carboxylated silica-coated photon-upconversion nanoparticles containing rare-earth elements (Y, Yb, and Er).

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Nanoparticles (NPs) applied to the surface of some solids can increase signals in inductively coupled plasma mass spectrometry (ICPMS). Drops containing 20 and/or 40 nm nanoparticles of Ag and/or Au were deposited on metallic and ceramic/glass samples, and after being dried, both the samples treated with NPs and plain targets were ablated by one pulse per spot. The laser ablation ICPMS (LA-ICPMS) signals were enhanced for metallic samples modified with NPs in comparison to signals produced at the plain, untreated surface.

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The purpose of this study is to investigate the time dependent growth of silica shells on CdTe quantum dots to get their optimum thicknesses for practical applications. The core/shell structured silica-coated CdTe quantum dots (CdTe/SiO₂ QDs) were synthesized by the Ströber process, which used CdTe QDs co-stabilized by mercaptopropionic acid. The coating procedure used silane primer (3-mercaptopropyltrimethoxysilane) in order to make the quantum dots (QDs) surface vitreophilic.

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We report on the toxicity and bioaccumulation of three different types of Cd-based quantum dots (QDs), dispersed in aqueous medium, for a model plant Allium cepa L. It is believed that encapsulation of nanoparticles should reduce their toxicity and increase their stability in different environments; in this work we studied how QD encapsulation affects their phytotoxicity. Core, core/shell, and core/shell/shell QDs (CdTe, CdTe/ZnS, and CdTe/CdS/ZnS QDs capped by 2-mercaptopropionic acid) were tested and CdCl was used as a positive control.

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The purpose of this study was to determine the toxicity of two different sources of cadmium, i.e. CdCl and Cd-based Quantum Dots (QDs), for freshwater model plant Lemna minor L.

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In this work, we proposed a new data acquisition approach that significantly improves the repetition rates of Laser-Induced Breakdown Spectroscopy (LIBS) experiments, where high-end echelle spectrometers and intensified detectors are commonly used. The moderate repetition rates of recent LIBS systems are caused by the utilization of intensified detectors and their slow full frame (i.e.

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