Sample preparation methods for determination of Cd, Pb and Sn in meat samples by GFAAS: use of acid digestion associated with a cold finger apparatus versus solubilization methods
TL;DR: In this paper, three sample preparation methods for the determination of Cd, Pb and Sn in meat by Graphite Furnace Atomic Absorption Spectrometry (GFAAS): acid digestion, solubilization with tetramethylammonium hydroxide and formic acid.
Abstract: The aim of this study was to present three sample preparation methods for the determination of Cd, Pb and Sn in meat by Graphite Furnace Atomic Absorption Spectrometry (GFAAS): acid digestion, solubilization with tetramethylammonium hydroxide and formic acid. For the digestion with HNO3, a conventional open system with a cold finger was used. This system helped to avoid losses of analytes and reagents by volatilization, permitting to operate at high temperatures applied at a digester block and reducing the digestion time (∼1 h). Solubilizations were performed at room temperature. The slurry was left standing overnight and remained closed until achieving complete solubilization. The temperature program of the graphite furnace was optimized for each element in the different means of preparation samples using a mixture of Pd–Mg. The figures of merit were similar for all sample preparation methods evaluated. The limits of detection obtained for the acid digestion procedure were 0.0006, 0.0164 and 0.0520 μg g−1 for Cd, Pb and Sn, respectively. In order to evaluate the accuracy of the results obtained by the three sample preparation methods, recovery tests for four real meat samples were performed and the recoveries ranged from 93.7 to 109%, supporting the accuracy of the method. Also, different certified reference materials of meat were analyzed and the results obtained were in agreement with the certified value at 95% of confidence (t-test). The best results were obtained by the acid digestion procedure with the cold finger system. This procedure is faster, the system is semi-closed with no significant contamination or loss of analytes by volatilization and it provides a better signal/noise ratio.
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TL;DR: In this article, the advantages, drawbacks and applications of the main techniques of sample preparation employed during the determinations of total mercury and methylmercury in food matrices employing analytical methods such as: cold vapor atomic absorption spectrometry (CV AAS) and atomic fluorescence spectrometer (AFS), inductively coupled plasma mass spectrometers (ICP-MS), voltammetry and neutron activation analysis.
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TL;DR: In this article, a comparative evaluation of three different methods for sample preparation in rice for As, Cd, Pb, and Se determination by graphite furnace atomic absorption spectrometry (GF AAS) is presented.
41 citations
TL;DR: XRD, FT-IR, SEM and nitrogen adsorption-desorption techniques have been used to characterization of prepared polymeric samples and FAAS technique was used to determination of Fe(III) ion in the foods and waters samples.
33 citations
Cites methods from "Sample preparation methods for dete..."
...After cooling to room temperature, 5 mL hydrogen peroxide was added to the mixture and heated for 1 h and resulting mixture was diluted by deionized water [21, 22], adjustment of the pH was performed by using of sodium hydroxide and hydrochloric acid....
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TL;DR: In this paper, a comparative study between three acid decomposition procedures of milk powder samples for the determination of Ca, Cu, Fe, K, and Na by optical emission spectrometry with inductively coupled plasma is presented.
Abstract: In this paper, a comparative study between three acid decomposition procedures of milk powder samples for the determination of Ca, Cu, Fe, K, and Na by optical emission spectrometry with inductively coupled plasma is presented. Utilizing a reflux system, it was possible to increase the temperature of the digester block above the boiling point of the reaction medium, avoiding the loss of analyte and the excessive evaporation of the acids during the heating. Conditions of acidity (10 mL HNO3/H2SO4), temperature (350 °C), and decomposition time (4 h) were defined by evaluation of residual carbon content. Acid digestion in an open system with a cold finger was compared with a conventional open system (4 h ate 120 °C), as well as with microwave digestion (heating ramp to 180 °C by the time 45 min), for four commercial samples of milk powder. For the three sample preparation procedures, the values of the analyte concentrations in all analyzed samples were similar. The accuracy of the acid digestion procedures for Ca, Cu, Fe, K, and Na was assessed by the analysis of a certified reference material of milk (infant formula), and good agreement between the certified values and the measured value was obtained. The limits of quantification for the acid digestion with reflux system for Ca, Cu, Fe, K, and Na, in milligram per kilogram, were 7.48, 0.31, 1.0, 8.20, and 25.81, respectively, and for the microwave digestion were 14.0, 0.57, 1.78, 14.65, and 46.08, respectively. The decomposition procedure using a cold finger in an open system is effective, presenting the lowest residual carbon content (6 %), good accuracy, and relative standard deviation lower than 5 %, and appears to be a suitable procedure for sample preparation for routine analysis.
20 citations
TL;DR: The acid decomposition method was applied for the sample preparation of processed fruit juice and indicated the absence of Cr, Zn and Cu in the samples, except for Cu in strawberry juice.
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TL;DR: While plant breeding and agronomic management can minimize soil–plant transfer of Cd, and maximize concentrations of antagonists to Cd assimilation in humans, it remains important that inputs of this metal to soil be minimized.
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TL;DR: In this article, the concentrations of heavy metals (Pb, Cd, Fe, Cu, Mn and Zn) in fish samples were determined using graphite furnace atomic absorption spectrometry after dry ashing and wet ashing methods.
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TL;DR: Considering the above-mentioned menace, efforts should be focused on the estimation of dietary intakes of potential toxic agents by consumers, and an analytical technique with sufficient sensitivity is required for the accurate determination of these chemicals in food samples.
Abstract: Exposure to environmental pollutants is an important problem of environmental toxicology. Heavy metals are regarded as toxic to living organisms because of their tendency to accumulate in selected tissues. Moreover, their presence is a causative agent of various sorts of disorders, including neuro-, nephro-, carcino-, terato-, and immunological. Exposures of human to environmental chemicals can occur simultaneously from various sources. One exposure route is ingestion of hazardous chemicals through contaminated food and beverages. Considering the above-mentioned menace, efforts should be focused on the estimation of dietary intakes of potential toxic agents by consumers. Dietary exposure assessment to nonnutrients is usually performed by combining 2 sets of data—the concentration of elemental contaminants in various food products and the consumption data of these food items. A variety of approaches exist for evaluating exposure to food chemicals, and the method chosen is influenced, among others, by the intended goal, the availability of data, cost, and time frame. Moreover, it is also important to note how accurate and detailed the information concerning toxic elements intake needs to be. There are a number of sources of food consumption data currently used in exposure assessments, which range from 1 d to habitual intake. Frequently, the heavy metals for which dietary exposure is of interest are present in trace and ultra-trace quantities. Hence, an analytical technique with sufficient sensitivity is required for the accurate determination of these chemicals in food samples. It is important to remember that the accuracy of quantitative analysis is strongly dependent on the sampling and preparation steps.
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TL;DR: In this paper, an overview of modern techniques of sample preparation for food analysis employing atomic and inorganic mass spectrometric techniques, such as flame atomic absorption, chemical vapor generation atomic absorption and atomic fluorescence spectrometry, graphite furnace atomic absorption spectrometer, inductively coupled plasma optical emission spectrometrization, and induction coupled plasma mass spectroscopy, is presented.
Abstract: The present article gives an overview of recent publications and modern techniques of sample preparation for food analysis employing atomic and inorganic mass spectrometric techniques, such as flame atomic absorption spectrometry, chemical vapor generation atomic absorption and atomic fluorescence spectrometry, graphite furnace atomic absorption spectrometry, inductively coupled plasma optical emission spectrometry, and inductively coupled plasma mass spectrometry. Among the most frequently applied sample preparation techniques for food analysis are dry ashing, usually with the addition of an ashing aid, and acid digestion, preferably with the assistance of microwave energy. Slurry preparation, particularly with the assistance of ultrasound, is increasingly used to reduce acid consumption and sample preparation time. Direct analysis of solid samples is gaining importance in the field of food analysis as it offers the highest sensitivity, avoids the use of acids and other aggressive reagents, make...
205 citations