The method for the analysis of vanadium in hexagonal mesoporous silica (V-HMS) catalysts using Laser Induced Breakdown Spectrometry (LIBS) was suggested. Commercially available LIBS spectrometer was calibrated with the aid of authentic V-HMS samples previously analyzed by ICP OES after microwave digestion. Deposition of the sample on the surface of adhesive tape was adopted as a sample preparation method. Strong matrix effect connected with the catalyst preparation technique (1st vanadium added in the process of HMS synthesis, 2nd already synthesised silica matrix was impregnated by vanadium) was observed. The concentration range of V in the set of nine calibration standards was 1.3-4.5% (w/w). Limit of detection was 0.13% (w/w) and it was calculated as a triple standard deviation from five replicated determinations of vanadium in the real sample with a very low vanadium concentration. Comparable results of LIBS and ED XRF were obtained if the same set of standards was used for calibration of both methods and vanadium was measured in the same type of real samples. LIBS calibration constructed using V-HMS-impregnated samples failed for measuring of V-HMS-synthesized samples. LIBS measurements seem to be strongly influenced with different chemical forms of vanadium in impregnated and synthesised samples. The combination of LIBS and ED XRF is able to provide new information about measured samples (in our case for example about procedure of catalyst preparation).

• MeSH
• Time Factors MeSH
• Chemistry Techniques, Analytical economics   methods   MeSH
• Catalysis MeSH
• Microscopy, Electron, Scanning MeSH
• Silicon Dioxide chemistry   MeSH
• Porosity MeSH
• Powders MeSH
• Spectrophotometry MeSH
• Vanadium analysis   chemistry   MeSH
• Particle Size MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

The manuscript presents a procedure for optimal sample preparation and the mapping of the spatial distribution of metal ions and nanoparticles in plant roots using laser-induced breakdown spectroscopy (LIBS) in a double-pulse configuration (DP LIBS) in orthogonal reheating mode. Two Nd:YAG lasers were used; the first one was an ablation laser (UP-266 MACRO, New Wave, USA) with a wavelength of 266nm, and the second one (Brilliant, Quantel, France), with a fundamental wavelength of 1064nm, was used to reheat the microplasma. Seedlings of Vicia faba were cultivated for 7 days in CuSO4 or AgNO3 solutions with a concentration of 10µmoll-1 or in a solution of silver nanoparticles (AgNPs) with a concentration of 10µmoll-1 of total Ag, and in distilled water as a control. The total contents of the examined metals in the roots after sample mineralization as well as changes in the concentrations of the metals in the cultivation solutions were monitored by ICP-OES. Root samples embedded in the TissueTek medium and cut into 40µm thick cross sections using the Cryo-Cut Microtome proved to be best suited for an accurate LIBS analysis with a 50µm spatial resolution. 2D raster maps of elemental distribution were created for the emission lines of Cu(I) at 324.754nm and Ag(I) at 328.068nm. The limits of detection of DP LIBS for the root cross sections were estimated to be 4pg for Cu, 18pg for Ag, and 3pg for AgNPs. The results of Ag spatial distribution mapping indicated that unlike Ag+ ions, AgNPs do not penetrate into the inner tissues of Vicia faba roots but stay in their outermost layers. The content of Ag in roots cultivated in the AgNP solution was one order of magnitude lower compared to roots cultivated in the metal ion solutions. The significantly smaller concentration of Ag in root tissues cultivated in the AgNP solution also supports the conclusion that the absorption and uptake of AgNPs by roots of Vicia faba is very slow. LIBS mapping of root sections represents a fast analytical method with sufficient precision and spatial resolution that can provide very important information for researchers, particularly in the fields of plant science and ecotoxicology.

• MeSH
• Plant Roots metabolism   MeSH
• Metal Nanoparticles chemistry   MeSH
• Lasers * MeSH
• Copper metabolism   MeSH
• Spectrum Analysis * MeSH
• Silver chemistry   metabolism   MeSH
• Vicia faba metabolism   MeSH
• Publication type
• Journal Article MeSH

• MeSH
• Adult MeSH
• Electromyography MeSH
• Rehabilitation MeSH
• Check Tag
• Adult MeSH
• Publication type
• Comparative Study MeSH

Zubní ankylóza je u člověka patologický proces, který vzniká přímou fúzí zubní tkáně s okolní kostí díky traumatům či zánětu v okolí zubu. Selháním interakce mezi těmito dvěma tkáněmi dochází k poruchám funkce zubu jako orgánu, která může vést k resorpci alveolární kosti. Tento stav končí často ztrátou zubu a vznikem podmínek nevhodných pro následnou rekonstrukci ztraceného zubu. Cílem projektu je odhalení buněčných a molekulárních procesů podílejících se na morfologických a funkčních změnách během vzniku zubní ankylózy u člověka. Projekt rovněž využije nové metodické přístupy jako LIBS, mikro CT analýzy či sledování změn exprese osteogenních faktorů v oblasti paradontu s cílem rozšířit znalosti o příčinách vzniku zubních ankylóz, jakož i možnosti preventivních přístupů při traumatech zubů.; Tooth ankyloses are pathological conditions in human, which arise by direct fusion of the tooth with surrounding tissues as a result of trauma or inflammation around teeth. Failure of interaction between these tissues lead to the disruption of tooth function as an organ and the resorption of alveolar bone. This state is followed by loss of teeth and by the initiation of conditions inappropriate for following teeth reconstruction. Aim of the project is to uncover cellular and molecular processes contributing to morphological and functional changes during tooth ankyloses initiation in human. Project will use new methodical approaches such as LIBS, micro CT examination or gene expression analyses of osteogenic factors in periodontal area with aim to expand our understanding about causes of teeth ankyloses commencement as well as possibilities of new approaches for their prevention during teeth traumas.

• Keywords
• ankylóza, ankyloses, zub, tooth, osteogenní markery, alveolární kost, LIBS, PCR Array, mikro CT, osteogenetic markers, alveolar bone, LIBS, PCR Array, micro CT,

• NML Publication type
• závěrečné zprávy o řešení grantu AZV MZ ČR

Laser-induced breakdown spectroscopy (LIBS) is a promising technique for the readout of immunochemical assays utilizing indirect detection of labels (Tag-LIBS), typically based on nanoparticles. We have previously demonstrated that Tag-LIBS immunoassay employing yttrium-based photon-upconversion nanoparticles (UCNPs) can reach sensitivity similar to commonly used enzyme and fluorescence immunoassays. In this study, we report on further increasing the sensitivity of UCNP-based Tag-LIBS immunoassay by employing magnetic microbeads (MBs) as the solid phase in the determination of cancer biomarker prostate-specific antigen. Due to the possibility of analyte preconcentration, MBs enabled achieving a limit of detection (LOD) of 4.0 pg·mL-1, representing two orders of magnitude improvement compared with equivalent microtiter plate-based assay (LOD of 460 pg·mL-1). In addition, utilizing MBs opens up the possibility of an internal standardization of the LIBS readout by employing iron spectral lines, which improves the assay robustness by compensating for LIBS signal fluctuations and bead-bound immunocomplexes lost throughout the washing steps. Finally, the practical applicability of the technique was confirmed by the successful analysis of clinical samples, showing a strong correlation with the standard electrochemiluminescence immunoassay. Overall, MB-based Tag-LIBS was confirmed as a promising immunoassay approach, combining fast readout, multiplexing possibilities, and high sensitivity approaching upconversion luminescence scanning while avoiding the requirement of luminescence properties of labels.

• MeSH
• Immunoassay methods   MeSH
• Lasers * MeSH
• Humans MeSH
• Limit of Detection * MeSH
• Microspheres MeSH
• Prostate-Specific Antigen * analysis   immunology   blood   MeSH
• Spectrum Analysis methods   MeSH
• Yttrium chemistry   radiation effects   MeSH
• Check Tag
• Humans MeSH
• Male MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

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. The NP labels were examined from the bottom of a standard 96-well microtiter plate. Thanks to the flexibility of LIBS instrumentation, both the plasma emission collection and the focusing optics arrangements can be collinearly arranged. The experiments showed that silver NPs and gold NPs can be readily quantified on the bottom of the microtiter plate. Utilizing this technique, a sandwich immunoassay for human serum albumin using streptavidin-coated AgNP labels was developed. The assay has a 10 ng·mL-1 detection limit which is comparable to the sensitivity of fluorometric readout. The main advantage of this LIBS technique is its wide scope in which it enables a detection of almost any type of NP labels, irrespective to any fluorescence or catalytic properties. Owing to the immediate signal response, the relatively simple instrumentation also enables assay automation. The LIBS capability of multi-elemental analyses makes it a promising and fast alternative to other readout techniques, in particular with respect to multiplexed detection of biomarkers. Graphical abstract Laser-induced breakdown spectroscopy (LIBS) is used as a novel readout method of nanoparticle-based immunoassays in microtiter plates. After formation of sandwich immunocomplex, the analyte concentration is quantified as the signal of Ag nanoparticle labels determined by LIBS.

• MeSH
• Biomarkers blood   MeSH
• Immunoassay methods   MeSH
• Metal Nanoparticles chemistry   MeSH
• Lasers * MeSH
• Humans MeSH
• Serum Albumin, Human analysis   MeSH
• Surface Properties MeSH
• Silver chemistry   MeSH
• Particle Size MeSH
• Gold chemistry   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

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. Here, we focus on implementing an internal standard into the LIBS elemental analysis of soft tissue samples. We achieve this by extending routine methodology for optimization of soft tissues analysis with a standard spiking method. This step enables a robust optimization procedure of LIBS experimental settings. Considering the implementation of LIBS analysis to the histological routine, we avoid further alterations of the tissue structure. Therefore, we propose a unique methodology of sample preparation, analysis, and subsequent data treatment, which enables the comparison of signal response from heterogenous matrix for different LIBS parameters. Additionally, a brief step-by-step process of optimization to achieve the highest signal-to-noise ratio (SNR) is described. The quality of laser-tissue interaction is investigated on the basis of the zinc signal response, while selected experimental parameters (e.g., defocus, gate delay, laser energy, and ambient atmosphere) are systematically modified.

• MeSH
• Cells MeSH
• Laser Therapy * MeSH
• Lasers * MeSH
• Reference Standards MeSH
• Spectrum Analysis MeSH
• Light MeSH
• Publication type
• Journal Article MeSH

This article reports on the utilization of X-ray microradiography and laser induced breakdown spectroscopy (LIBS) techniques for investigation of the metal accumulation in different part of leaf samples. The potential of the LIBS-analysis for finding the proper plant species for phytoremediation is compared with the results of microradiography measurements at the HERCULES source at ENEA, Rome (Italy) and X-ray microradiography experiments at the ELETTRA Synchrotron, Trieste (Italy).

• MeSH
• Financing, Organized MeSH
• Helianthus chemistry   MeSH
• Cadmium analysis   MeSH
• Plant Roots chemistry   MeSH
• Lasers MeSH
• Plant Leaves chemistry   MeSH
• Microradiography MeSH
• Lead analysis   MeSH
• Scattering, Radiation MeSH
• X-Rays MeSH
• Spectrum Analysis MeSH
• Synchrotrons instrumentation   MeSH

Correlative imaging of cutaneous tumors provides additional information to the standard histopathologic examination. However, the joint progress in the establishment of analytical techniques, such as Laser-Induced Breakdown Spectroscopy (LIBS) and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) in clinical practice is still limited. Their combination provides complementary information as it is also shown in our study in terms of major biotic (Ca, Mg, and P) and trace (Cu and Zn) elements. To elucidate changes in the elemental composition in tumors, we have compiled a set of malignant tumors (Squamous Cell Carcinoma, Basal Cell Carcinoma, Malignant Melanoma, and Epithelioid Angiosarcoma), one benign tumor (Pigmented Nevus) and one healthy-skin sample. The data processing was based on a methodological pipeline involving binary image registration and affine transformation. Thus, our paper brings a feasibility study of a practical methodological concept that enables us to compare LIBS and LA-ICP-MS results despite the mutual spatial distortion of original elemental images. Moreover, we also show that LIBS could be a sufficient pre-screening method even for a larger number of samples according to the speed and reproducibility of the analyses. Whereas LA-ICP-MS could serve as a ground truth and reference technique for preselected samples.

• MeSH
• Carcinoma, Basal Cell diagnostic imaging   MeSH
• Mass Spectrometry methods   MeSH
• Laser Therapy MeSH
• Lasers MeSH
• Humans MeSH
• Melanoma diagnostic imaging   pathology   MeSH
• Skin Neoplasms * diagnostic imaging   pathology   MeSH
• Nevus, Pigmented diagnostic imaging   MeSH
• Spectrum Analysis methods   MeSH
• Carcinoma, Squamous Cell diagnostic imaging   pathology   MeSH
• Trace Elements analysis   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH

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/SiO2 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. These results were compared to two other sources of cadmium, free Cd ions (CdCl2) and prime un-shell nanoparticles CdTe QDs. Tested compounds were applied in concentrations representing 20 and 200 μM Cd. The uptake and translocation of Cd were investigated using inductively coupled plasma optical emission spectrometry (ICP-OES) and the spatial Cd distribution was investigated in detail applying laser induced breakdown spectroscopy (LIBS). The LIBS maps with a lateral resolution of 100 μm were constructed for the whole plants, and maps with a lateral resolution of 25 μm (micro-LIBS arrangement) were used to analyse only the most interesting parts of plants with Cd presence (e.g. root tips or a part crossing the root into the above-ground part). Our results show that the bioaccumulation patterns and spatial distribution of Cd in CdTe/SiO2 QDs-treated plants differ from the plants of positive control and CdTe QDs. Fluorescence microscopy photographs revealed that CdTe/SiO2 became adsorbed onto the plant surface in comparison to CdTe QDs. Further, a physico-chemical characterization of QDs before and after the test exposure showed only minor changes in the nanoparticle diameters and no tendencies of QDs for agglomeration or aggregation during the exposure.

• MeSH
• Adsorption MeSH
• Bioaccumulation MeSH
• Sodium Chloride MeSH
• Microscopy, Fluorescence MeSH
• Sinapis metabolism   MeSH
• Cadmium MeSH
• Quantum Dots chemistry   toxicity   MeSH
• Silicon Dioxide chemistry   MeSH
• Cadmium Compounds chemistry   toxicity   MeSH
• Tellurium chemistry   MeSH
• Publication type
• Journal Article MeSH