9 research outputs found

    Application of Hyphenated Techniques in Speciation Analysis of Arsenic, Antimony, and Thallium

    Get PDF
    Due to the fact that metals and metalloids have a strong impact on the environment, the methods of their determination and speciation have received special attention in recent years. Arsenic, antimony, and thallium are important examples of such toxic elements. Their speciation is especially important in the environmental and biomedical fields because of their toxicity, bioavailability, and reactivity. Recently, speciation analytics has been playing a unique role in the studies of biogeochemical cycles of chemical compounds, determination of toxicity and ecotoxicity of selected elements, quality control of food products, control of medicines and pharmaceutical products, technological process control, research on the impact of technological installation on the environment, examination of occupational exposure, and clinical analysis. Conventional methods are usually labor intensive, time consuming, and susceptible to interferences. The hyphenated techniques, in which separation method is coupled with multidimensional detectors, have become useful alternatives. The main advantages of those techniques consist in extremely low detection and quantification limits, insignificant interference, influence as well as high precision and repeatability of the determinations. In view of their importance, the present work overviews and discusses different hyphenated techniques used for arsenic, antimony, and thallium species analysis, in different clinical, environmental and food matrices

    Chlorates(VII) removal on Dowex™PSR-2 resin

    Get PDF
    Lately there has been observed the increased presence of chlorates(VII) in the natural environment which can affect human health negatively. Therefore the removal of chlorate(VII) ions using the gel type resin functionalized with the tri-n-butyl ammonium (Dowex™PSR-2) from waters was studied. The main aim was to evaluate the effects of experimental conditions including contact time, initial solution concentration, pH and temperature on chlorate(VII) ions removal as well as the anion exchanger properties on chlorate(VII) ions sorption. It was found that only the pseudo second order model described the experimental data well and the intraparticle diffusion was not the rate-limiting step. According to the Freundlich model, the qe value was to be 69.26 mg/g at optimum conditions (pH 7.0 at 25 oC)

    Comparison of Physicochemical, Mechanical, and (Micro-)Biological Properties of Sintered Scaffolds Based on Natural- and Synthetic Hydroxyapatite Supplemented with Selected Dopants

    Get PDF
    The specific combinations of materials and dopants presented in this work have not been previously described. The main goal of the presented work was to prepare and compare the different properties of newly developed composite materials manufactured by sintering. The synthetic-(SHAP) or natural- (NHAP) hydroxyapatite serves as a matrix and was doped with: (i) organic: multiwalled carbon nanotubes (MWCNT), fullerenes C60, (ii) inorganic: Cu nanowires. Research undertaken was aimed at seeking novel candidates for bone replacement biomaterials based on hydroxyapatite—the main inorganic component of bone, because bone reconstructive surgery is currently mostly carried out with the use of autografts; titanium or other non-hydroxyapatite -based materials. The physicomechanical properties of the developed biomaterials were tested by Scanning Electron Microscopy (SEM), Dielectric Spectroscopy (BSD), Nuclear Magnetic Resonance (NMR), and Differential Scanning Calorimetry (DSC), as well as microhardness using Vickers method. The results showed that despite obtaining porous sinters. The highest microhardness was achieved for composite materials based on NHAP. Based on NMR spectroscopy, residue organic substances could be observed in NHAP composites, probably due to the organic structures that make up the tooth. Microbiology investigations showed that the selected samples exhibit bacteriostatic properties against Gram-positive reference bacterial strain S. epidermidis (ATCC 12228); however, the property was much less pronounced against Gram-negative reference strain E. coli (ATCC 25922). Both NHAP and SHAP, as well as their doped derivates, displayed in good general compatibility, with the exception of Cu-nanowire doped derivates

    Chemometric and environmental assessment of arsenic, antimony, and chromium speciation form occurrence in a water reservoir subjected to thermal anthropopressure

    No full text
    <div>In the study, arsenic, antimony, and chromium concentrations and selected physicochemical parameters in water and sediment samples from the thermal anthroporessure subjected Rybnik Reservoir (Poland) were determined. As(III), As(V), Sb(III), and Sb(V) ions were successfully separated on Dionex IonPac AS7 column, and Cr(III) and Cr(VI) on Dionex IonPac AG7 column. The obtained limits of detection were 0.18, 0.22, 0.009, 0.012, 0.11, and 0.17 μg/L, respectively. Water and bottom sediment samples were collected monthly at three-point transect between January and November 2013. The As(III) and Sb(III) speciation forms dominated in the bottom water, and Cr(VI) concentration in the bottom water was twice as high as the value measured for the surface water. The oxidized arsenic, antimony, and chromium forms</div><div>dominated in the bottom sediments in the heated water discharge zone of the Rybnik Power Plant. The location of sampling point had a significant influence on the observed transformations and contents of the analyzed speciation forms. The chemometric analysis coupled with the dissimilarity analysis and principal component analysis helped to visualize the variability in the concentrations of the element speciation forms within the researched period and analyzing correlations.</div

    Psychometric properties and validation of the polish version of the Fibromyalgia Impact Questionnaire (FIQ-Pol)

    No full text
    Abstract Background Fibromyalgia (FM) is a chronic condition characterized by widespread musculoskeletal pain, fatigue, intestinal disorders, mood swings, and sleep disturbances. To the best of our knowledge, the questionnaire used for assessing problems and difficulties in the functioning of people with FM has not been translated and adapted in Poland so far. The aim of the study was to assess the psychometric properties of the Polish version of the Fibromyalgia Impact Questionnaire (FIQ-Pol). Material and method The study covered 150 people with FM living in Poland. The measurement reliability, internal structure, repeatability, and validity of the Polish version of the FIQ were examined. Results The scale score reliability of the entire tool for the research group was very good. The alpha Cronbach's test result for the whole scale was 0.84. The repeatability of the scale measured by the test–retest method using the interclass correlation coefficients (ICC) was very good and amounted to 0.96. Internal structure suggested by FIQ-Pol authors was confirmed (Confirmatory factor analysis). After introducing modification indices for the entire scale, satisfactory parameter values were obtained, i.e.: RMSEA (0.06), CFI (0.97) and TLI (0.96). Theoretical validity was assessed by correlating the results of the Polish version of the FIQ with the results of the Beck's Depression Inventory (BDI). Both the FIQ-Pol total score and its domains showed strong positive correlations with BDI. Conclusion The Polish FIQ is a reliable and valid tool to measure the functional disability and health status of Polish people with FM

    Composite Nanofibers Containing Multiwall Carbon Nanotubes as Biodegradable Membranes in Reconstructive Medicine

    No full text
    International audienceWe have tested titanium (Ti) plates that are used for bone reconstruction in maxillofacial surgery, in combination with five types of novel long-resorbable biomaterials: (i) PCL 0-polycaprolactone without additives, (ii) PCL MWCNT-polycaprolactone with the addition of multiwall carbon nanotubes (MWCNT), (iii) PCL OH-polycaprolactone doped with multiwall carbon nanotubes (MWCNT) containing-OH hydroxyl groups, (iv) PCL COOH-polycaprolactone with the addition of multiwall carbon nanotubes (MWCNT) containing carboxyl groups, and (v) PCL TI-polycaprolactone with the addition of Ti nanoparticles. The structure and properties of the obtained materials have been examined with the use of Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), and/or X-ray powder diffraction (XRD). Titanium BR plates have been covered with: (i) PCL 0 fibers (PCL 0BR-connection plates), (ii) PCL MWCNT fibers (PCL MWCNTBR-plates), (iii) PCL OH fibers (PCL OHBR-plates), (iv) PCL COOH (PCL COOHBR-plates), (v) PCL TI fiber (PCL TIBR-connection plates). Such modified titanium plates were exposed to X-ray doses corresponding to those applied in head and neck tumor treatment. The potential leaching of toxic materials upon the irradiation of such modified titanium plates, and their effect on normal human dermal fibroblasts (NHDF) have been assessed by MTT assay. The presented results show variable biological responses depending on the modifications to titanium plates
    corecore