Metals In Biological Materials Research Articles

Биологиялық материал құрамындағы ауыр металдардың салыстырмалы сараптамасы

Биологиялық материал құрамындағы ауыр металдардың салыстырмалы сараптамасы

Quantification of the titanium content in metallodrug-exposed tumor cells using HR-CS AAS

AbstractHigh-resolution continuum source atomic absorption spectroscopy (HR-CS AAS) is a valuable analytical technique for metal quantification because of its high sensitivity and selectivity for metal atoms as well as its improved background correction mode. However, the quantification of metals in biological materials, e.g. cell lysates, is still challenging because of matrix effects and other experimental complications. A method to quantify the titanium content of tumor cells exposed to titanium-based drugs was developed using HR-CS AAS. This method allows the quantification of titanium in cell suspensions in the low µg L

Development of a Unified X-ray Fluorescence Procedure for Determining Heavy Metals in Biological Materials

A unified procedure for the X-ray fluorescence determination of Pb, Mo, Rb, As, Zn, Ni, Fe, and Mn in biological materials was developed using the internal standard technique (gallium was the reference element). The samples were prepared for analysis by ashing the materials. The effects of variations in the chemical composition and of the surface density of unsaturated radiators on the accuracy of the analytical results were studied with the use of theoretical intensities; this effect varied from 2.5 to 22%. Based on this information, an optimum calibration function was chosen. Ashes of plant and animal tissues can be analyzed with the use of this function. The errors due to sample preparation for analysis and the reproducibility and accuracy of the results of X-ray fluorescence analysis were evaluated.

Multi-elemental speciation studies of trace elements associated with metallothionein-like proteins in mussels by liquid chromatography with inductively coupled plasma time-of-flight mass spectrometric detection

The analytical potential of complementary chromatographic separations such as size exclusion (SEC) plus anion-exchange chromatography coupled with inductively coupled plasma time-of-flight mass spectrometry (ICP-TOF-MS), was evaluated for the multi-elemental speciation of trace elements associated with methallothionein-like proteins (MLPs) in mussel hepatopancreas. The initial separation of the proteins is performed by 'off-line' SEC, collecting fractions which are then analysed for the trace elements by ICP-TOF-MS in small sample volumes. Further purification is accomplished by the separation of the different proteins contained in the above obtained MLP fraction on a Mono Q (HR 5/5) anion-exchange column [fast protein liquid chromatography (FPLC)], using an ammonium acetate gradient at a physiological pH of 7.4 as the mobile phase. The separated proteins are detected 'on-line' by UV absorption at 254 and 280 nm. Specific detection (16 metals) with on-line ICP-TOF-MS was also performed. This hybrid approach was applied to investigate the metal binding patterns of the proteins expressed by mussels which had been previously exposed to 16 trace metals in an aquarium tank for 1 and 2 weeks. The exceptional characteristics of ICP-TOF-MS for quasi-simultaneous monitoring of many trace elements in transient signals are illustrated by this 'on-line' coupling to FPLC separation, paving the way to virtually simultaneous multi-elemental speciation of trace metals in biological material.

On-line separation and sequential determination of trace amounts of heavy metals in biological materials by flow injection inductively coupled plasma atomic emission spectrometry

A flow injection inductively coupled plasma atomic emission spectrometric method for the sequential determination of trace amounts of heavy metals (Cd, Co, Cu and Zn) in biological samples is described based on the complexation of the metal ions with 1,5-bis (di-2-pyridyl) methylene thiocarbohydrazide and its subsequent on-line extraction into isobutyl methyl ketone. A systematic study was performed to determine the optimum conditions for the continuous extraction of the metals. Detection limits for Cu, Co, Zn and Cd ranged from 1.1 to 23.0 ng ml–1 with precision varying from 1.2 to 3.7% relative standard deviation at 100 ng ml–1. These values were obtained under simultaneous multi-element conditions. The effect of various foreign ions on the determination of these metals by the proposed method was examined under the optimum working conditions. The tolerance limits found showed that they can be determined in the presence of a variety of ions including most of those that commonly occur with them in natural samples. Accuracy and matrix interference were confirmed by standard additions and use of certified reference materials.

Synchrotron X-ray absorption spectroscopy: a new tool for actinide and lanthanide speciation in solids and solution

Synchrotron-based X-ray absorption near-edge structure spectroscopy and extended X-ray absorption fine structure spectroscopy are powerful techniques to study many chemical elements in solids, liquids and gases. Information can be obtained on the speciation and complexation of lanthanide and actinide elements and other radionuclides in aqueous and non-aqueous solutions, on adsorption processes at the solid-water interface of these solutions with soils, minerals, mineral assemblies and uranium mill tailings, and on the adsorption and incorporation of these metals in biological materials. A literature review on synchrotron studies of these processes is given. The conceptual design of an experimental hard X-ray synchrotron beam line end station for the investigation of radioactive samples is described.

Potentiometric stripping analysis of selected heavy metals in biological materials

Different biological materials such as edible oils, refined and unrefined cane and beet sugar and tea (black and green) leaves were assayed for the heavy metals cadmium, copper, lead and zinc. The results revealed significant differences in heavy metal contents within each class of the biological materials (P < 0.05). Cadmium was not detectable in sugar samples. Among the oils, highest amounts of copper (0.263 microgram/g) and lead (0.154 microgram/g) were in corn oil and zinc in olive oil (3.01 micrograms/g) whereas cadmium exhibited a narrow range (0.023-0.033 microgram/g). The samples of beet-sugar generally contained higher levels of the heavy metals than cane-sugar. Black and green tea leaves contained 0.411-0.908 microgram Cd/g, 6.500-9.220 micrograms Cu/g, 2.200-5.238 micrograms Pb/g, and 14.500-25.180 micrograms Zn/g.

Application of the slurry technique to biological materials: a survey of literature

The literature on the application of the slurry technique to biological materials is reviewed. It is obvious from the various applications that the most frequently employed atomization method for slurry analysis in biological materials is electrothermal atomization using either graphite tube or platform atomizers. The slurry technique is particularly useful when certified reference materials are not available and when the standard addition method is to be avoided. The literature survey revealed that this technique compares favourably with other methods for the determination of trace metals in biological materials.

12] Atomic absorption spectrometry

Publisher Summary Atomic absorption methods are the most widely used for the determination of metals in biological materials. This chapter discusses an overview of the field to help in the selection among the available techniques. The various elements will then be treated with recommendations for preferred methodology. This chapter discusses the understanding that atomic absorption is two techniques: flame atomic absorption (AAS) and furnace AAS. Flame AAS is generally the best analytical technique available for samples that are most easily collected as solutions, if the analyte concentration is above the mg/liter range in the solution. Precision of about 1% is routinely obtained and better precision is available if extra care is taken in the preparation of standards and if slightly more time-consuming methods are used. There are several problems that stand in the way of increased utilization of furnace AAS for trace metal analyses. More importantly, many analysts fail to give adequate attention to the laboratory hygiene that is required at the very low levels accessible by furnace AAS.

Use of external calibration for the determination of trace metals in biological materials by inductively coupled plasma mass spectrometry

Inductively coupled plasma mass spectrometry (ICP-MS) was used for the analysis of two marine biological materials (cod liver tissue and shellfish tissue). A rapid dissolution of the materials was achieved by digestion in pressurised vessels in a microwave oven. Twelve elements (Cr, Fe, Mn, Ni, Cu, Zn, As, Ag, Cd, Sn, Hg and Pb) were then determined. It was possible to obtain accurate results by external calibration (i.e., the use of standard solutions), even at sub-µg g–1 levels. Internal standardisation using 40Ar40Ar was carried out when required to correct for instrumental drift. The isotope dilution technique generally gave more accurate and precise results, especially at the lower concentration levels.

Methodological studies on the determination of trace metals in biological tissues

The purpose of this investigation was to establish a practical and accurate method for analyzing heavy metals in biological materials, particularly in edible animals.This paper describes a simple method of biological tissue sample preparation, the Mild Digestion Method, which can be used for the analysis of various metals, and what is compared M-D with the conventional method, the Complete Dogestion Method, C-D which is sulfuric acid, nitric acid, perchloric acid digestion. The tissue was added to 2 to 2.5 times its own volume of concentrated nitric acid and heated at a relatively low temperature (95-100°C), overnight. The product was directly used as a specimen for flame-AAS and non-flameAAS without any further chemical treatment. The following results were obtained:1) The method was simple enough to prevent errors by contamination during the pretreatment process.2) Only a small amount of nitric acid was required for digestion when an adequate apparatus and heating temperature were selected. The final volume was adequate for analysis. Additionally, the nitric acid inhibited the interference of the large amounts of sodium and potassium which existed in the biological materials.3) Using this method, the measurement of metals at the ppm level was achieved by flame-AAS, and at the ppb level by non-flameAAS. The method, however, was inadequate for the analysis of arsenic without further chemical treatment.4) The respective recovery (%) and the detection limits (ng/ml) by non-flameAAS were as follows: Cadmium 101 and 0.02, Lead 98 and 0.71, Manganese 108 and 0.21, Nickel 108 and 0.34, and Chromium 106 and 0.50.The method was concluded to be simple, accurate and practically useful.

A semiautomated system for analysis of metals in biological materials and its application to mass determination of cadmium in blood

A semiautomated system was developed for the determination of metals in biological materials by the combination of block-digestion-autosampler-flameless atomic absorption spectrophotometry. For block-digestion which can mineralize 144 samples in 10 h, a Pyrex micro Kjeldahl tube of a special shape was designed. When applied to the mass analyses of cadmium in 1761 blood samples from non-exposed subjects, the system as a whole was sensitive enough with the lowest detection limit of 0.2 ng cadmium/ml blood, and able to measure about 50 samples every day, essentially without aid. Experiences are described with necessary comments.

A rapid screening method for heavy metals in biological materials by emission spectroscopy

A semi-quantitative screening method for heavy metals in biological material is described. The metals are complexed with ammonium pyrrolidine dithiocarbamate, sodium diethyl dithiocarbamate and potassium sodium tartrate. The solutions are adjusted to pH 4 and then extracted into chloroform. The chloroform phase is evaporated onto a matrix mixture of lithium fluoride and graphite. The sample is analysed by direct current arc emission spectroscopy using a 3 metre grating spectrograph. The spectra are recorded on a photographic plate. The method is developed on aqueous and spiked samples and then applied to in vivo samples containing toxic levels of heavy metals. Atomic absorption spectroscopy is used to check standard concentrations and to monitor the efficiency of the extraction procedure.

Animal models for the study of trace metal requirements.

In this paper six of the trace elements which are essential for optimum human health will be considered. These are copper, zinc, manganese, molybdenum, chromium and selenium. For each element the realization that it may be essential for man was preceded by the demonstration of a similar dependence either in experimental animals or in livestock inadvertently deprived of the micronutrient. This account will review the value of animal models in identifying possible human requirements for a trace metal and while it is not reliable to extrapolate from such studies to man in determining human quantitative requirements the important contribution which animal studies have made in identifying factors which modify quantitative requirements for these elements will also be outlined. Early this century the ubiquity of trace amounts of certain metals in biological material stimulated efforts to investigate their possible biological function (Underwood, 1977). Cu was reported to be essential for growth and haemoglobin synthesis in rats in 1928 (Hart et al. 1928) and soon afterwards endemic nutritional Cu deficiency was recognized in cattle. Hart and his colleagues feeding rats purified diets then succeeded in demonstrating that Mn and Zn were essential micronutrients, and subsequently these dependencies have been shown in all species studied (Underwood, 1977). Further investigations using purified diets have enabled the identification of Mo, Cr and Se as essential dietary components in animals. More recently, the use of plastic isolators fitted with filters and airlocks to exclude atmospheric dust (Smith & Schwarz, 1967) and create ‘trace element sterile environments’ has provided evidence that tin, nickel, silicon, vanadium, arsenic, lead and cadmium may be essential. None of these elements have been shown to be essential for man. Extension of experience with animals to man has been slow. The possibility that Zn deficiency may contribute to the features of human vitamin deficiency states was considered soon after the original studies with Zn deficient animal studies (Eggleton, 1939) but it was not until the 1960s, in Iran and Egypt, that human Zn deficiency syndromes were identified (Prasad, 1978). These patients exhibited some features of Zn deficiency in common with the earlier description in animals. They had growth retardation with delayed skeletal maturation, icthyosis and hypogonadism. An associated anaemia responded to Fe supplements but the other manifestations only resolved after oral Zn supplements had been given. The more florid features of Zn deficiency such as parakeratosis, eczematous dermatitis, alopecia, impaired immunity and diarrhoea were not observed in man until it was realized that the features of acrodermatitis enteropathica were those of a profound w29-6651/80/3933-4105 fo1.w 0 1980 The Nutrition Society

Photon activation analysis of trace metals in biological materials via collection of metal tropolone-5-sulfonate complexes onto anion-exchange resin

Tropolone-5-sulfonic acid was used to separate and collect trace elements as their complexes onto an anion-exchange resin in photon-activation of biological materials. Retention behaviour of the anionic complexes of Cr, Mn, Fe, Co, Ni, Cu, Zn, and Pb on Dowex 1-X8 resin was examined with respect to pH, amount of resin, concentration of the ligand, and coexisting salt anions, using radioisotope tracers. Under optimum conditions, Cr, Mn, Co, Ni, Zn and Pb were collected from the irradiated samples of NBS-SRM Orchard Leaves, NBS-SRM Spinach, green tea and black tea on the marcket. The analytical results agreed with certified values and the reproducibility was good.

The application of metal-coated graphite tubes to the determination of trace metals in biological materials: I. The determination of lead in blood using a tungsten-coated graphite tube

A new technique is introduced in trace metal determinations in biological materials by coating the graphite tube with tungsten by a highly reproducible process. This coating appeared to be responsible for the prevention of residue formation that occurred in untreated graphite tubes when lead in blood was analyzed. The life of the graphite tube was thus increased by about 300% for this matrix.

多用途微量金属分析装置による生物試料中の金属定量I

多用途微量金属分析装置による生物試料中の金属定量I

多用途微量金属分析装置による生物試料中の金属定量II

多用途微量金属分析装置による生物試料中の金属定量II

Atomic absorption spectrometry of trace metals in clinical pathology

Atomic absorption spectrometry provides a convenient and versatile instrumental method for measurements of trace metals in biological materials. An important innovation is the recent development of nonflame atomization devices, which have substantially improved the analytical sensitivity of atomic absorption spectrometry. Applications of atomic absorption spectrometry of trace metals in clinical pathology have been expanded by the recent recognition of clinical syndromes associated with copper and zinc deficiency, and the discovery of abnormalities of chromium and nickel metabolism in various human diseases.

Detection limits in analysis of metals in biological materials by laser microprobe optical emission spectrometry.

Detection limits in analysis of metals in biological materials by laser microprobe optical emission spectrometry.