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Radomír Malina

Bio: Radomír Malina is an academic researcher from Brno University of Technology. The author has contributed to research in topics: Laser-induced breakdown spectroscopy & Laser ablation. The author has an hindex of 12, co-authored 32 publications receiving 638 citations. Previous affiliations of Radomír Malina include Central European Institute of Technology.

Papers
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Journal ArticleDOI
TL;DR: The use of laser-induced breakdown spectroscopy (LIBS) for trace element determination in different matrices is reviewed in this article, where the main emphasis is on spatially resolved analysis of microbiological, plant and animal samples.

155 citations

Journal ArticleDOI
TL;DR: In this paper, single-pulse laser-Induced Breakdown Spectroscopy (LIBS) and Laser-Ablation Inductively Coupled Plasma Mass-Spectrometry (LA-ICP-MS) were applied for mapping the silver and copper distribution in Helianthus Annuus L.
Abstract: Single-pulse Laser-Induced Breakdown Spectroscopy (LIBS) and Laser-Ablation Inductively Coupled Plasma Mass-Spectrometry (LA-ICP-MS) were applied for mapping the silver and copper distribution in Helianthus Annuus L. samples treated with contaminant in controlled conditions. For Ag and Cu detection the 328.07 nm Ag(I) and 324.75 nm Cu(I) lines were used, respectively. The LIBS experimental conditions (mainly the laser energy and the observation window) were optimized in order to avoid self-absorption effect in the measured spectra. In the LA-ICP-MS analysis the Ag 107 and Cu 63 isotopes were detected. The capability of these two analytical techniques for high-resolution mapping of selected trace chemical elements was demonstrated.

70 citations

Journal ArticleDOI
TL;DR: The intended aim of this work is to create a database for simple and fast identification of archeological or paleontological materials in situ, which can speed up and simplify the sampling process during archeological excavations that nowadays tend to be quite damaging and timeconsuming.

67 citations

Journal ArticleDOI
24 Jan 2008-Sensors
TL;DR: Investigation of sunflower plants response on stress induced by silver(I) ions found that the treated plants embodied growth depression, coloured changes and lack root hairs, and basic biochemical indicators of environmental stress were investigated.
Abstract: The aim of this work is to investigate sunflower plants response on stressinduced by silver(I) ions. The sunflower plants were exposed to silver(I) ions (0, 0.1, 0.5,and 1 mM) for 96 h. Primarily we aimed our attention to observation of basic physiologicalparameters. We found that the treated plants embodied growth depression, coloured changes and lack root hairs. Using of autofluorescence of anatomical structures, such aslignified cell walls, it was possible to determine the changes of important shoot and rootstructures, mainly vascular bungles and development of secondary thickening. Thedifferences in vascular bundles organisation, parenchymatic pith development in the rootcentre and the reduction of phloem part of vascular bundles were well observable.Moreover with increasing silver(I) ions concentration the vitality of rhizodermal cellsdeclined; rhizodermal cells early necrosed and were replaced by the cells of exodermis.Further we employed laser induced breakdown spectroscopy for determination of spatialdistribution of silver(I) ions in tissues of the treated plants. The Ag is accumulated mainlyin near-root part of the sample. Moreover basic biochemical indicators of environmentalstress were investigated. The total content of proteins expressively decreased withincreasing silver(I) ions dose and the time of the treatment. As we compare the resultsobtained by protein analysis - the total protein contents in shoot as well as root parts - wecan assume on the transport of the proteins from the roots to shoots. This phenomenon canbe related with the cascade of processes connecting with photosynthesis. The secondbiochemical parameter, which we investigated, was urease activity. If we compared theactivity in treated plants with control, we found out that presence of silver(I) ions markedlyenhanced the activity of urease at all applied doses of this toxic metal. Finally we studiedthe effect of silver(I) ions on activity of urease in in vitro conditions.

63 citations

Journal ArticleDOI
TL;DR: In this article, the development and implementation of analytical methodology for investigating elemental accumulation in different layers within plant leaves, with in-situ spatial resolution mapping, exploiting the technique of LIBS.

63 citations


Cited by
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Journal Article
TL;DR: In this article, a fast Fourier transform method of topography and interferometry is proposed to discriminate between elevation and depression of the object or wave-front form, which has not been possible by the fringe-contour generation techniques.
Abstract: A fast-Fourier-transform method of topography and interferometry is proposed. By computer processing of a noncontour type of fringe pattern, automatic discrimination is achieved between elevation and depression of the object or wave-front form, which has not been possible by the fringe-contour-generation techniques. The method has advantages over moire topography and conventional fringe-contour interferometry in both accuracy and sensitivity. Unlike fringe-scanning techniques, the method is easy to apply because it uses no moving components.

3,742 citations

Journal ArticleDOI
TL;DR: The current state-of-the-art of analytical LIBS is summarized, providing a contemporary snapshot of LIBS applications, and highlighting new directions in laser-induced breakdown spectroscopy, such as novel approaches, instrumental developments, and advanced use of chemometric tools are discussed.
Abstract: The first part of this two-part review focused on the fundamental and diagnostics aspects of laser-induced plasmas, only touching briefly upon concepts such as sensitivity and detection limits and largely omitting any discussion of the vast panorama of the practical applications of the technique. Clearly a true LIBS community has emerged, which promises to quicken the pace of LIBS developments, applications, and implementations. With this second part, a more applied flavor is taken, and its intended goal is summarizing the current state-of-the-art of analytical LIBS, providing a contemporary snapshot of LIBS applications, and highlighting new directions in laser-induced breakdown spectroscopy, such as novel approaches, instrumental developments, and advanced use of chemometric tools. More specifically, we discuss instrumental and analytical approaches (e.g., double- and multi-pulse LIBS to improve the sensitivity), calibration-free approaches, hyphenated approaches in which techniques such as Raman and fluorescence are coupled with LIBS to increase sensitivity and information power, resonantly enhanced LIBS approaches, signal processing and optimization (e.g., signal-to-noise analysis), and finally applications. An attempt is made to provide an updated view of the role played by LIBS in the various fields, with emphasis on applications considered to be unique. We finally try to assess where LIBS is going as an analytical field, where in our opinion it should go, and what should still be done for consolidating the technique as a mature method of chemical analysis.

1,159 citations

Journal ArticleDOI
TL;DR: Compared to the conventional flame emission spectroscopy, LIBS atomizes only the small portion of the sample by the focused laser pulse, which makes a tiny spark on the sample, and capturing the instant light is a major skill to collect sufficient intensity of the emitting species.
Abstract: ■ CONTENTS General Information: Books, Reviews, and Conferences 640 Fundamentals 641 Interaction of Laser Beam with Matter 641 Factors Affecting Laser Ablation and LaserInduced Plasma Formation 642 Influence of Target on the Laser-Induced Plasmas 642 Influence of Laser Parameters on the LaserInduced Plasmas 643 Laser Wavelength (λ) 643 Laser Pulse Duration (τ) 643 Laser Pulse Energy (E) 645 Influence of Ambient Gas on the Laser-Induced Plasmas 645 LIBS Methods 647 Double Pulse LIBS 647 Femtosecond LIBS 651 Resonant LIBS 652 Ranging Approaches 652 Applications 654 Surface Inspection, Depth Profiling, and LIBS Imaging 654 Cultural Heritage 654 Industrial Analysis 655 Environmental Monitoring 656 Biomedical and Pharmaceutical Analysis 658 Security and Forensics 659 Analysis of Liquids and Submerged Solids 660 Space Exploration and Isotopic Analysis 662 Space Exploration 662 Isotopic Analysis 662 Conclusions and Future Outlook 663 Author Information 664 Corresponding Author 664 Notes 664 Biographies 664 Acknowledgments 664 References 664

847 citations

Book ChapterDOI
01 Jan 2018
TL;DR: Laser induced breakdown spectroscopy (LIBS) as discussed by the authors is a technique where atoms and ions are primarily formed in their excited states as a result of interaction between a tightly focused laser beam and the material sample.
Abstract: Laser induced breakdown spectroscopy (LIBS) is basically an emission spectroscopy technique where atoms and ions are primarily formed in their excited states as a result of interaction between a tightly focused laser beam and the material sample. The interaction between matter and high-density photons generates a plasma plume, which evolves with time and may eventually acquire thermodynamic equilibrium. One of the important features of this technique is that it does not require any sample preparation, unlike conventional spectroscopic analytical techniques. Samples in the form of solids, liquids, gels, gases, plasmas and biological materials (like teeth, leaf or blood) can be studied with almost equal ease.LIBS has rapidly developed into a major analytical technology with the capability of detecting all chemical elements in a sample, of real- time response, and of close-contact or stand-off analysis of targets. The present book has been written by active specialists in this field, it includes the basic principles, the latest developments in instrumentation and the applications of LIBS. It will be useful to analytical chemists and spectroscopists as an important source of information and also to graduate students and researchers engaged in the fields of combustion, environmental science, and planetary and space exploration. It features: recent research work, possible future applications and LIBS Principles.

611 citations

Journal ArticleDOI
TL;DR: The aim of this review is to provide an overview of the most recent achievements in trace metal imaging while at the same time also offering a historical perspective of this rapidly evolving research field.
Abstract: Approximately a third of the human proteome contains metal cations, either in form of cofactors with catalytic functions, or as structural support elements.1,2 To guarantee a proper maintenance of this metal ion pool, both at the cellular and whole organism levels, nature has evolved a highly sophisticated machinery comprised of a complex interplay between DNA, proteins, and biomolecules.3 Over the past decades, a steadily growing number of diseases have been identified, which are characterized by metal imbalance in cells and tissues. Among the most prominent examples rank Alzheimer’s disease and Parkinson’s disease, two neurodegenerative disorders that involve abnormal accumulation of transition metals in brain tissue.4 While some progress has been made at understanding the molecular basis of these disorders, many important questions remain unanswered. For example, little is known about the cellular structures that are involved in transiently storing metal ions prior to their incorporation into metalloproteins or the fate of metal ions upon protein degradation. An important first step towards unraveling the regulatory mechanisms involved in trace metal transport, storage, and distribution represents the identification and quantification of the metals, ideally in context of their native physiological environment in tissues, cells, or even at the level of individual organelles and subcellular compartments. Since the inception of the first histochemical methods for the microscopic demonstration of transition metals in tissues more than 140 years ago,5 many highly sensitive microanalytical techniques and instruments have been developed for the in situ analysis of trace metals. The aim of this review is to provide an overview of the most recent achievements in trace metal imaging while at the same time also offering a historical perspective of this rapidly evolving research field. Although this survey has been structured according to the various analytical techniques, particular emphasis is given to the biological background for a better understanding of the context and importance of each discussed study. An overview of the most important microanalytical techniques currently available for the in situ detection of trace metals in cells and tissues is compiled in Table 1. Depending on the task, each technique may offer specific advantages and, of course, also disadvantages. Currently, synchrotron- and focused ion-beam microprobes presumably offer the best combination of sensitivity and spatial resolution; however, the ionizing high-energy excitation beam is not compatible with studying live organisms. Conversely, techniques that have been specifically developed for physiological imaging in clinical medicine, notably magnetic resonance imaging and positron emission tomography, inherently offer only a low spatial resolution and are merely suitable for obtaining information at the organ or tissue level. Although fluorescence microscopy based methods provide very high sensitivity down to the single molecule level while being at the same time compatible with live cell and tissue studies, scattering and limited penetration depth renders these techniques unsuitable for imaging opaque specimens. There are also important differences regarding the type of quantitative information that can be gained by each of these analytical techniques. For example, the histochemical detection with chromogenic and fluorogenic dyes relies on a competitive exchange of the metal ion within its native environment, most likely coordinated to endogenous ligands. Depending on the exchange kinetics and thermodynamic affinity of the histochemical indicator, only a fraction of the total metal ion contents in a cell or tissue can be probed. Nevertheless, this kinetically labile pool is particularly of interest in context of understanding the uptake, distribution, and regulation of trace elements at the cellular level, and in this regard, these methods offer unique opportunities to dynamically image metal ion fluxes in live cells with high sensitivity and spatial resolution. At the same time, organelles and proteins of interest can be readily labeled with genetically encoded green fluorescent protein tags,12 thus providing direct insights into dynamic processes within a larger cellular and biochemical context. In contrast, similar correlative information is difficult to gain with the fully quantitative micro beam methods, which require xenobiotic elemental tags for identifying subcellular structures. Autoradiographic tracer experiments offer much improved resolution over PET; however, the technique is only applicable to fixed or frozen tissues and cells. Furthermore, tracer studies cannot provide direct information regarding the endogenous metal composition of cells or tissues, and are therefore primarily limited to metal uptake, distribution, and release studies. Finally, mass spectrometric analyses are surface-based methods that destroy the sample while measuring its elemental composition. Clearly, only the combination of several analytical techniques and specific biochemical studies may lead to a fully comprehensive analysis of a biological system. Table 1 Spatially resolved microanalytical techniques for in situ imaging of trace metals in biology.6–11 2. Histochemical Techniques Histology is the branch of biology dealing with the study of microscopic anatomy of cells and tissues of plants and animals. Histological studies are typically carried out on thin sections of tissue or with cultured cells. To visualize and identify particular structures, a broad spectrum of histological stains and indicators are available. Among the most widely used dyes are hematoxylin and eosin, which stain nuclei blue and the cytoplasm pink, respectively.13 The history of detecting biological trace metal by histological methods dates back more than 140 years. Although these techniques have been today mostly replaced by the much more sensitive modern analytical methods described in this review article, histochemical approaches for visualizing metals mark the very beginning in the exploration of the inorganic physiology of transition metals. Given this special place in history, we deemed it necessary to briefly review some of the early achievements in this field. 2.1. Chromogenic Detection with Chelators and Ligands Ever since the inception of Perls Prussian blue method for staining of non-heme iron, numerous indicators have been developed for the in situ visualization of trace metals in biological tissues and cells.13 Due to their limited sensitivity; however, most of these techniques were only suitable for the diagnosis of pathological conditions, typically associated with excess metal accumulations, thus preventing their application for routine staining of normal tissue. Furthermore, because the dyes are engaged in a competitive exchange equilibrium with endogenous ligands, histological stains are not suitable for the analytical determination of the total metal contents in tissues and thus limited to the visualization of the histologically reactive fraction of loosely bound labile metal ions. 2.1.1. Histochemistry of Iron The histochemical demonstration of labile iron reported by Perls in 1867 is among the earliest accounts describing the in situ visualization of a trace metal in biological tissues.5 The method was originally described by Grohe, who observed the formation of a blue coloration when he treated cadaver tissues with potassium ferrocyanide in acidic solution.14 Due to its low cost and simplicity, the technique is still used today for the histological visualization of non-heme iron. Some variations focused on optimizing the concentrations and proportions of the reagents,15–17 among which Lison’s protocol17 appears to be most popular today. An intensification of Perls’ staining can be obtained by exploiting the use of ferric ferrocyanide in catalyzing the oxidation of diaminobenzidine (DAB) to polymeric benzidine black by hydrogen peroxide.18 An alternative method employs the reaction of ferricyanide with Fe(II) resulting in Turnbull blue.19 Since almost all of the Fe in tissues is in the ferric form, the staining procedure requires the in situ conversion of Fe(III) to Fe(II) with ammonium sulfide.15 Due to often incomplete reduction, the method never gained much attention. More recently, an application of Turnbull blue, named the ‘perfusion Turnbull method’ has been developed, where in vivo perfusion of acidic ferricyanide is followed by DAB intensification.20 The direct in vivo perfusion avoids artifacts associated with tissue fixation, including the loss of loosely bound iron and oxidation of Fe(II) to Fe(III). Similarly, Perls method was modified by employing in vivo perfusion with acidic ferrocyanide. Both methods are capable of identifying organs and tissues containing histochemically reactive iron over a broad pH range, including the low endosomal pH.21,22 The history of iron histochemistry would be incomplete without mentioning Quincke’s method, which employed ammonium sulfide for the precipitation of tissue iron as its sulfide.23 A detailed account on the various techniques, including a comprehensive historical overview of non-heme iron chemistry, has been recently published.24

506 citations