Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
1,304
result(s) for
"Spectrophotometry, Atomic - methods"
Sort by:
Assessment of toxic elements in the samples of different cigarettes and their effect on the essential elemental status in the biological samples of Irish hypertensive consumers
2015
Cigarette smoking causes an acute increase in blood pressure and heart rate and has been found to be associated with malignant hypertension (HT). A significant flux of toxic metals among other toxins reaches the lungs through smoking. In the present study, the relationship between essential (zinc and selenium) and toxic element (TE; cadmium and mercury) and HT incidence in smoker and nonsmoker population living in Dublin, Ireland was investigated. The zinc (Zn), selenium (Se), cadmium (Cd) and mercury (Hg) were determined in biological (scalp hair and blood) samples of smoker and nonsmoker hypertensive patients. For comparison purposes, healthy age- and sex-matched subjects as referents residing in the same city were also selected. The different brands of cigarette consumed by the studied population were also analyzed for Cd and Hg. The concentrations of essential trace and TEs in all studied samples were measured by inductively coupled plasma atomic emission spectrophotometer after microwave-assisted acid digestion. The validity and accuracy of the methodology was checked using certified reference materials (CRMs). The recovery of all the studied elements was found to be in the range of 96.4–99.7% of certified values of CRMs. The filler tobacco of different branded cigarettes contains Hg and Cd concentrations in the range of 9.55–12.4 ng and 1.70–2.12 μg per cigarette, respectively. The results of this study showed that the mean values of Cd and Hg were significantly higher in scalp hair and blood samples of hypertensive patients as compared with healthy controls, whereas Zn and Se concentrations were found to be lower in hypertensive patients, the difference was significant in the case of smoker patients (
P
<0.001). The levels of both TEs were 2–3-folds higher in scalp hair and blood samples of nonhypertensive smoker subjects as compared with nonsmoker controls. It was observed that exposure of TEs via cigarette smoking may be synergistic with other risk factors associated with HT.
Journal Article
Acellular Normal and Fibrotic Human Lung Matrices as a Culture System for In Vitro Investigation
by
Hadley, Ryan
,
Cornett, Ashley M.
,
Weiss, Kevin
in
Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy
,
Biological and medical sciences
,
Blood coagulation. Blood cells
2012
Extracellular matrix (ECM) is a dynamic tissue that contributes to organ integrity and function, and its regulation of cell phenotype is a major aspect of cell biology. However, standard in vitro culture approaches are of unclear physiologic relevance because they do not mimic the compositional, architectural, or distensible nature of a living organ. In the lung, fibroblasts exist in ECM-rich interstitial spaces and are key effectors of lung fibrogenesis.
To better address how ECM influences fibroblast phenotype in a disease-specific manner, we developed a culture system using acellular human normal and fibrotic lungs.
Decellularization was achieved using treatment with detergents, salts, and DNase. The resultant matrices can be sectioned as uniform slices within which cells were cultured.
We report that the decellularization process effectively removes cellular and nuclear material while retaining native dimensionality and stiffness of lung tissue. We demonstrate that lung fibroblasts reseeded into acellular lung matrices can be subsequently assayed using conventional protocols; in this manner we show that fibrotic matrices clearly promote transforming growth factor-β-independent myofibroblast differentiation compared with normal matrices. Furthermore, comprehensive analysis of acellular matrix ECM details significant compositional differences between normal and fibrotic lungs, paving the way for further study of novel hypotheses.
This methodology is expected to allow investigation of important ECM-based hypotheses in human tissues and permits future scientific exploration in an organ- and disease-specific manner.
Journal Article
Recent Advances in the Determination of Major and Trace Elements in Plants Using Inductively Coupled Plasma Optical Emission Spectrometry
2024
Interest in measuring major and trace elements in plants has increased in recent years because of growing concerns about the elements’ contribution to daily intakes or the health risks posed by ingesting vegetables contaminated by potentially toxic elements. The recent advances in using inductively coupled plasma atomic emission spectrometry (ICP-OES) to measure major and trace elements in plant samples are reviewed in the present work. The sample preparation before instrumental determination and the main advantages and limitations of ICP-OES are described. New trends in element extraction in liquid solutions using fewer toxic solvents and microextractions are observed in recently published literature. Even though ICP-OES is a well-established and routine technique, recent innovations to increase its performance have been found. Validated methods are needed to ensure the obtaining of reliable results. Much research has focused on assessing principal figures of merit, such as limits of detection, quantification, selectivity, working ranges, precision in terms of repeatability and reproducibility, and accuracy through spiked samples or certified reference materials analysis. According to the published literature, the ICP-OES technique, 50 years after the release of the first commercially available equipment, remains a powerful and highly recommended tool for element determination on a wide range of concentrations.
Journal Article
A Friendly Complexing Agent for Spectrophotometric Determination of Total Iron
by
Sanna, Gavino
,
Spano, Nadia
,
Nurchi, Valeria M.
in
Calibration
,
Colorimetry - methods
,
Deferoxamine - chemistry
2021
Iron, one of the most common metals in the environment, plays a fundamental role in many biological as well as biogeochemical processes, which determine its availability in different oxidation states. Its relevance in environmental and industrial chemistry, human physiology, and many other fields has made it necessary to develop and optimize analysis techniques for accurate determination. Spectrophotometric methods are the most frequently applied in the analytical determination of iron in real samples. Taking advantage of the fact that desferrioxamine B, a trihydroxamic acid used since the 1970s in chelation therapy for iron overload treatment, forms a single stable 1:1 complex with iron in whichever oxidation state it can be found, a smart spectrophotometric method for the analytical determination of iron concentration was developed. In particular, the full compliance with the Lambert-Beer law, the range of iron concentration, the influence of pH, and the interference of other metal ions have been taken into account. The proposed method was validated in terms of LoD, LoQ, linearity, precision, and trueness, and has been applied for total iron determination in natural water certified material and in biological reference materials such as control human urine and control serum.
Journal Article
Determination of trace cobalt ions in bottled drinking water samples from Fiji Island by spray-assisted fine droplet formation-liquid phase microextraction based on simultaneous complexation and extraction before flame atomic absorption spectrometer measurement
by
Arvas, Büşra
,
Yolaçan, Çiğdem
,
Sağsöz, Oğuzhan
in
Atmospheric Protection/Air Quality Control/Air Pollution
,
Atomic absorption analysis
,
atomic absorption spectrometry
2023
In this study, a green, simple and effective preconcentration method named as spray-assisted fine droplet formation-liquid phase microextraction (SAFDF-LPME) before the flame atomic absorption spectrophotometry (FAAS) measurement for cobalt determination was developed. The method reduces the external dispersive solvent usage by using a simple spraying apparatus to obtain fine droplets of the extraction solvent. SAFDF-LPME method also consists of simultaneous complexation and extraction which indicates the environmental benevolence of the developed method. This method minimized the relative errors with high repeatability and accuracy by reducing the experimental steps. The influential parameters such as buffer type, buffer solution volume, extraction solvent/ligand solution volume (spraying cycle), and mixing period were systematically optimized by the univariate optimization procedure. With the optimum parameters applied, the detection power of the FAAS system was enhanced to about 110-folds with respect to 2.2 ng mL
−1
detection limit calculated for the proposed method. Bottled drinking water samples from Fiji Islands were used to demonstrate the applicability of the developed method for the accurate determination of trace cobalt in real sample matrices. Percent recovery results obtained between 95.5 and 88.5% showed the suitability of the developed method in the determination of cobalt at trace levels even in complex sample matrices.
Journal Article
Magnetic ionic liquid-based dispersive liquid-liquid microextraction technique for preconcentration and ultra-trace determination of Cd in honey
by
Wuilloud, Rodolfo G
,
Fiorentini, Emiliano F
,
Escudero, Leticia B
in
Acetonitrile
,
Ammonium
,
Atomic absorption analysis
2018
A simple, highly efficient, batch, and centrifuge-less dispersive liquid-liquid microextraction method based on a magnetic ionic liquid (MIL-DLLME) and electrothermal atomic absorption spectrometry (ETAAS) detection was developed for ultra-trace Cd determination in honey. Initially, Cd(II) was chelated with ammonium diethyldithiophosphate (DDTP) at pH 0.5 followed by its extraction with the MIL trihexyl(tetradecyl)phosphonium tetrachloroferrate(III) ([P6,6,6,14]FeCl4) and acetonitrile as dispersant. The MIL phase containing the analyte was separated from the aqueous phase using only a magnet. A back-extraction procedure was applied to recover Cd from the MIL phase using diluted HNO3 and this solution was directly injected into the graphite furnace of ETAAS instrument. An extraction efficiency of 93% and a sensitivity enhancement factor of 112 were obtained under optimal experimental conditions. The detection limit (LOD) was 0.4 ng L−1 Cd, while the relative standard deviation (RSD) was 3.8% (at 2 μg L−1 Cd and n = 10), calculated from the peak height of absorbance signals. This work reports the first application of the MIL [P6,6,6,14]FeCl4 along with the DLLME technique for the successful determination of Cd at trace levels in different honey samples.
Journal Article
Development of an analytical method for determination of lead and cadmium in biological materials by GFAAS using Escherichia coli as model substance
2022
In this work, an analytical method was developed for the determination of lead and cadmium in biological samples using graphite furnace atomic absorption spectrometry. Escherichia coli ( E . coli ) was chosen as model substance for this purpose as it is readily available in most laboratories and can be quickly and easily prepared with a high turnaround rate. Four different sample preparation methods were initially evaluated with respect to percent recovery, limit of detection, and limit of quantification, and the most promising one was developed further. The final process involving microwave assisted digestion of the sample with nitric acid and hydrogen peroxide showed high recovery, repeatability, and specificity. The process was first applied to lead and then extended for the determination of cadmium in the same E . coli substrates. Finally, to validate the process, a certified references material was analyzed, and the results obtained were evaluated with respect to accuracy by comparing them to the reported ones.
Journal Article
Nanometer-sized materials for solid-phase extraction of trace elements
2015
This review presents a comprehensive update on the state-of-the-art of nanometer-sized materials in solid-phase extraction (SPE) of trace elements followed by atomic-spectrometry detection. Zero-dimensional nanomaterials (fullerene), one-dimensional nanomaterials (carbon nanotubes, inorganic nanotubes, and nanowires), two-dimensional nanomaterials (nanofibers), and three-dimensional nanomaterials (nanoparticles, mesoporous nanoparticles, magnetic nanoparticles, and dendrimers) for SPE are discussed, with their application for trace-element analysis and their speciation in different matrices. A variety of other novel SPE sorbents, including restricted-access sorbents, ion-imprinted polymers, and metal–organic frameworks, are also discussed, although their applications in trace-element analysis are relatively scarce so far.
Graphical Abstract
Nanometer-sized materials for solid-phaseextraction of trace elements and their species
Journal Article
Insights into the Versatility of Using Atomic Absorption Spectrometry in Antibacterial Research
by
Krüger, David
,
Mukhtar, Muhammad Dauda
,
Matshwele, James T. P.
in
Anti-Bacterial Agents - chemistry
,
Anti-Bacterial Agents - pharmacology
,
Antibiotics
2024
The ongoing development of bacterial resistance to antibiotics is a global challenge. Research in that field is thus necessary. Analytical techniques are required for such a purpose. From this perspective, the focus was on atomic absorption spectrometry (AAS). Although it is old, AAS often offers unexpected potential. Of course, this should be exploited. The aim was therefore to demonstrate the versatility of the technique in antibacterial research. This is illustrated by various examples of its practical application. AAS can be used, for example, to confirm the identity of antibacterial compounds, for purity controls, or to quantify the antibiotics in pharmaceutical preparations. The latter allowed analysis without laborious sample preparation and without interference from other excipients. In addition, AAS can help elucidate the mode of action or resistance mechanisms. In this context, quantifying the accumulation of the antibiotic drug in the cell of (resistant) bacteria appears to play an important role. The general application of AAS is not limited to metal-containing drugs, but also enables the determination of some organic chemical antibiotics. Altogether, this perspective presents a range of applications for AAS in antibacterial research, intending to raise awareness of the method and may thus contribute to the fight against resistance.
Journal Article
Evaluation of the Elemental Composition of Dietary Supplements Containing Iron Available on the Polish Market Using ICP-OES, FAAS and CVAAS Techniques
by
Klimaszewska, Martyna
,
Maćkiewicz, Elżbieta
,
Szynkowska-Jóźwik, Małgorzata Iwona
in
Anemia
,
Bioavailability
,
Breastfeeding & lactation
2025
The Polish dietary supplement market is undergoing rapid development, driven by an increasing societal interest in preventative healthcare and the utilisation of products that have demonstrated efficacy. Poland is a leading European dietary supplement market, driven by a number of factors, including increased nutritional awareness, an ageing population, and intensive marketing efforts by manufacturers. In this study, the elemental composition of 24 dietary supplements containing iron, folic acid, and other vitamins and essential macro- and micronutrients was examined using CV AAS, F AAS, and ICP-OES techniques. The samples analysed included supplements intended for pregnant and breastfeeding women, supplements for individuals struggling with anaemia, and multivitamin supplements containing a complete set of both vitamins and minerals. In order to ensure the accuracy of the product, the mineral doses listed in the package inserts were also verified. The study’s findings revealed significant discrepancies between the doses declared by manufacturers and the doses obtained through analysis, particularly with regard to iron and zinc. Furthermore, an inconsistency was observed between the mineral doses and the values recommended by Polish law.
Journal Article