Determination Of Cadmium Research Articles

Fabrication and Characterizations of Axial View Liquid Electrode Plasma Atomic Emission Spectrometry for the Sensitive Determination of Trace Zinc, Cadmium, and Lead.

Axial view liquid electrode plasma-atomic emission spectrometry (axial view LEP-AES) was proposed and fabricated successfully in this work. The emission spectra from Zn, Cd, Pb, Ca, and K were applied for characterization and optimization. Comparing with conventional radial view LEP-AES devices, the newly designed axial view-LEP provided better sensing ability toward trace heavy metals. Moreover, pulsed voltage discharge was found to be advantageous over continuous discharge under the same discharge time for detection. The optimized parameters facilitate the limit of detection to achieve 0.24, 0.051, and 0.85 μg L-1 for Zn, Cd, and Pb, respectively. Furthermore, the axial view LEP-AES possessed excellent reproducibility and good durability. The real sample tests using two different certified reference water samples revealed the great potential of the axial view LEP-AES as a novel practical elemental analysis tool.

Emulsion breaking-induced extraction of Cd and Pb from oily dietary supplements followed by graphite furnace atomic absorption spectrometry detection

A method is described for the determination of cadmium (Cd) and lead (Pb) in oily dietary supplements using extraction induced by emulsion breaking (EIEB) and high-resolution continuum-source graphite furnace atomic absorption spectrometry (HR-CS GFAAS). The method is based on the formation of a water-in-oil emulsion by the addition of an extractor solution consisting of 5 % (w/v) Triton X-100% and 15 % (v/v) hydrochloric acid (HCl) to the sample of oil diluted with 1.5 mL of toluene and the breakage of this emulsion by centrifugation (4000 rpm for 5 min). Two well-defined phases were formed and the acid aqueous phase containing extracted Cd and Pb ions was analyzed by HR-CS GFAAS. Different parameters that influence the extraction efficiency of Cd and Pb were optimized univariately. The detection limits were 3.32 μg kg−1 for Pb and 1.51 μg kg−1 for Cd. A matrix-based calibration method was applied to compensate for the interference caused by the matrix effects. The Cd concentration in the samples ranged from 8.81 to 9.35 μg kg−1 and the highest concentration of Pb was 19.91 μg kg−1. The proposed preparation of sample through extraction by breaking emulsions of oily dietary supplements proved to be a simple and efficient strategy to determine the amount of Pb and Cd by HR-CS GFAAS.

Development of an analytical method for determination of lead and cadmium in biological materials by GFAAS using Escherichia coli as model substance.

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.

Separation, Preconcentration, and Determination of Lead, Cadmium, and Iron Using Cloud Point Extraction with Flame Atomic Absorption Spectrometry

Separation, Preconcentration, and Determination of Lead, Cadmium, and Iron Using Cloud Point Extraction with Flame Atomic Absorption Spectrometry

Metal decorated silica-based core-shell magnetic nanocomposite for the solid-phase microextraction of cadmium(II) with determination by high-resolution continuum source flame atomic absorption spectrometry

The present study describes a facile and environmentally friendly hydrothermal method for the fabrication of metal decorated silica-based core-shell magnetic nanocomposite M@Si-MNCs, applied as a sustainable coating material for the solid-phase microextraction of toxic cadmium ions. M@Si-MNCs were characterized by scanning electron microscopy, X-ray-diffraction, Fourier transform infrared spectroscopy and Brunauer–Emmett–Teller analyzer. Relevant parameters have been studied to obtain maximum recovery, including pH, adsorbent dosage, model solution volume, - adsorption and desorption time, and matrix effects. The developed method obtained excellent linearity from 50 to 500 µg/L with a limit of detection of 1.2 µg/L and a limit of quantification of 4.1 µg/L. The new method was applied for separation, preconcentration and determination of cadmium in environmental and tobacco samples.

An improved electrochemical sensor based on triton X-100 functionalized SnO2 nanoparticles for ultrasensitive determination of cadmium

The drastic increases in the concentration of heavy metals ions in the environment have become a serious concern for a number of years. Heavy metals pose serious impacts on human and aquatic life and cause severe health hazards. Amongst heavy metals, cadmium is known for its lethal effects on human health as it easily reacts with enzymes and creates free radicals in the biological system that causes carcinogenicity and other serious diseases. Thus, to tackle this challenge, TX-100 SnO2 nanoparticles based chemically modified sensor is introduced to assess the quantity of Cd+2 in the water system. The engineered SnO2 nanoparticles were electrochemically characterized through cyclic voltammetry and electrochemical impedance spectroscopy to ensure the better charge transfer kinetics and electrocatalytic properties of fabricated sensors. Under the optimized conditions e.g., scan rate 80 mV/s, PBS electrolyte pH 7, and potential window (−0.2 to −1.4 V), the engineered TX-100/SnO2/GCE-based sensor manifested a phenomenal response for cadmium ions in water media. The LOD and LOQ of developed TX-100/SnO2/GCE were calculated in the nanomolar range as 0.0084 nM and 0.27 nM. The recovery values of the proposed method for Cd+2 were found in an acceptable limit that witnesses the effectiveness of the fabricated sensor. Moreover, the excellent stability and anti-interference behavior of the sensor highlights its dynamic profile to be commercially utilized for the determination of Cd+2 ions in water bodies.

Optimization of magnetic ionic based dispersive liquid-liquid microextraction of cadmium in water and food samples using experimental design prior to flame atomic absorption spectrophotometry

A magnetic ionic based dispersive liquid liquid microextraction (MIL-DLLME) procedure was optimized for the analysis and extraction of cadmium in water and food samples by flame atomic absorption spectrophotometry (FAAS). Contribution of experimental variables were optimized through central composite design combined with response surface analysis. Under optimized conditions, the limit of detection was found 0.6 ng mL−1 with the relative standard deviation of 1.7%. Dynamic range was obtained in the concentration range of 2–700 ng mL−1 with correlation coefficient of 0.9983. Relative recoveries were ranged from 94% to 99% with enrichment factor of 172. The validation of the optimized method was successfully confirmed by reference material analysis. The optimized method allows the analysis of cadmium in water and food samples with good reliability of the determination. Compared with the conventional procedures, the method enabled a fast, green and simple determination of cadmium in the real sample with minimal solvent consumption and a higher extraction capability.

A successive homogeneous liquid-liquid microextraction based on solidification of switchable hydrophilicity solvents and ionic liquids for the detection of pyrethroids and cadmium in drinks

A simple, efficient, and environmentally friendly method for the determination of pyrethroids and cadmium in drink samples was developed by successive homogeneous liquid-liquid microextraction (SHLLME) based on switchable hydrophilicity solvents and ionic liquids coupled with high-performance liquid chromatography-diode array detector (HPLC-DAD) and graphite furnace atomic absorption spectrometry (GFAAS) detection. The extraction of pyrethroids needs to be conducted under acidic conditions, while cadmium needs to be extracted under neutral or slightly alkaline conditions. In SHLLME, hydrophobic fatty acids and ionic liquids were generated in situ as extraction solvents for pyrethroids and cadmium, respectively. Acidic ionic liquids and sodium carbonate were successively applied to adjust the pH value of the sample solution. The SHLLME procedure was optimized by univariate analysis and the Box-Behnken response surface methodology. Optimum conditions were as follows: 105 mg of sodium decanoate, 246 mg of [Emim][HSO4], 131 mg of sodium fluoroborate amount, and 128 mg of sodium carbonate. Under optimized conditions, the extraction recovery varied from 77.0% to 97.2%, and relative standard deviations varied from 0.5% to 4.5%. The limits of detection were 0.6 μg L−1 and 0.006 μg L−1 for pyrethroids and cadmium, respectively. This established method has the potential to continuously extract compounds with different physical and chemical properties.

Determination of arsenic, cadmium, mercury, lead and nickel as elemental impurities in atorvastatin calcium by inductively coupled mass spectrometer.

Atorvastatin calcium is employed as front-line treatment for cardiovascular diseases. According to the international conference on harmonization (ICH) guideline ICH Q3D, elemental impurities can come into drug products from various sources. These elemental impurities do not have any therapeutic benefit to the end-user. On the contrary, it harms the normal physiological system. Class 1 elements like arsenic, cadmium, mercury, and lead are inorganic impurities that can cause toxic effects on the human body. Nickel was used as a catalyst during the synthesis process of atorvastatin calcium. It comes under the Class-2A, can cause toxicity to humans, and must be quantified. A simple, fast, reliable inductively coupled plasma mass spectrometric method for the estimation of elemental impurities like arsenic, cadmium, mercury, lead, and nickel in atorvastatin calcium by open sample digestion technique was developed and validated in accordance with ICH Q3D and USP < 232 > and USP <233 > general chapter. Internal standards like indium, terbium, thallium, bismuth and yttrium were used to correct the non-spectral interferences that were generated during analysis. Gold was added to all solutions as it preserves mercury by amalgamation. The system performance was evaluated every time my performing system suitability parameters. The limits for all the elements were fixed in accordance with ICH Q3D. The limit of detection and the limit of quantification for all the five elements were estimated. Method specificity was proven by checking for interferences due to the sample matrix and other elements. Linearity of each element in standards was established from 25% to 200% of sample concentration, and correlation coefficients were found to be not less than 0.999. The accuracy of the method was demonstrated at three spiking levels at 50%, 100%, and 150% of the J-value for all the elements. The recoveries for all elements at each level were within the range of 90-120%. Method precision was proved at 100% J-value. The relative standard deviation of all elements was less than 5%. It concludes that this newly developed and validated reliable inductively coupled plasma mass spectrometric method for estimating of elemental impurities like arsenic, cadmium, mercury, lead, and nickel in atorvastatin calcium was within the permitted limit and suitable for routine use.

Metal-Phase Microextraction (MPME) as a Novel Solvent-Free and Green Sample Preparation Technique: Determination of Cadmium in Infant Formula and Real Water Samples

Metal-Phase Microextraction (MPME) as a Novel Solvent-Free and Green Sample Preparation Technique: Determination of Cadmium in Infant Formula and Real Water Samples

A novel ion- selective electrode sensor based on crafted polymer sugar thia crown ether for the determination of Cadmium (II)

A Cadmium (II) ion-selective electrode (ISE) based on Thia polymeric crown ether (SPCE-Cd2+) as a membrane carrier in a PVC matrix was successfully built for the determination of Cd2+ ions. Using Dimethyl phthalate (DMP) plasticizer, the electrode showed a Nernstian liner response spanning the range of 1*10-1 to 1*10-7 M with a slope of (28) ±2 mV per decade charge and a detection limit of 1*10-9 M. The sensor has a 10-second response time. The cadmium ion-selective electrode is highly precise in its selectivity for Cd2+ over other cations. Some alkali and transition metal ions have selectivity coefficients in the range of 1 * 10-7 to 1 * 10-1. It worked well as an indicator electrode in the potentiometric measurement of the cadmium ion.

Polystyrene-coated magnetic nanoparticles based dispersive solid phase extraction for the determination of cadmium in cigarette ash prior to slotted quartz tube flame atomic absorption spectrometry system

A sensitive, accurate and simple analytical method was developed to determine cadmium by slotted quartz tube-flame atomic absorption spectrometry after preconcentration/extraction with polystyrene coated magnetic nanoparticles based dispersive solid phase extraction. The surface of Fe3O4 based magnetic nanoparticles was modified with polystyrene to yield higher selectivity and sensitivity in adsorption efficiency of cadmium. The nanoparticles were dispersed into the aqueous solution to extract/separate cadmium. Significant parameters of the method including magnetic nanoparticle amount, mixing effect, effect of ionic strength, eluent concentration and sonication period were optimized to achieve optimal conditions for the analyte. The limit of detection and quantification values of the developed method were found to be 0.62 and 2.1ng/mL, respectively. Under the optimum conditions, enhancement of the detection power for cadmium were calculated as 102 folds for the developed method. The developed method was then applied to cigarette ash to test its accuracy and applicability. Total cadmium was found to be between 402 and 450ng/g in the ashes of different cigarette brands commercially available in Turkey. The accuracy of quantifying cadmium in the complex ash samples was enhanced by using the matrix matching calibration strategy. The developed method provides sensitive and selective determination of cadmium at ng/mL levels even at complex cigarette ash samples. High percent recovery results (90-102%) were obtained from spiked real samples.

A Hybrid Screen-Printed Strip for Enhanced Electroanalysis towards Lead and Cadmium in Multi-Matrices

Although heavy metals represent a major treat for ecosystem and human health, reference methods for their monitoring are characterized by time-consuming procedures, skilled personel and sophisticated equipment (e.g. ICP-MS, AAS). The development of portable solutions is required, particularly improving interventions and reducing complexity. To this regards, an electrochemical strip for the determination of lead and cadmium in clinical, environmental and food matrices have been developed. The Bismuth film-based flexible device has been optimized and it has been able to detect cadmium and lead, respectively, down to the detection limit of 1.3 and 2 ppb. The use of Whatman No.1 chromatographic paper has allowed to improve the sensitivity towards the detection of heavy metals, because of the porosity that allowed to pre-concentrate species. This led to an improvement in the sensitivity, with a detection limit of 0.3 and 0.5 ppb, respectively, to cadmium and lead, and offers the possibility to tune the sensitivity according to needs, e.g., improving the number of pre-concentration steps. Subsequently, the application of the electrochemical sensor in drinking water, mussel and blood serum was evaluated, demonstrating how these hybrid polyester-paper electrochemical strips can significantly lower the time and costs for on-site measurements, through analytical methods of simple use. The accuracy has been evaluated by comparison with ICP-MS measurements, giving satisfactory results.

Stripping voltammetric determination of cadmium and lead ions based on a bismuth oxide surface-decorated nanoporous bismuth electrode

Ultrasensitive detection of heavy metal ions through electrochemical methods is a longstanding research topic. One of the most compelling subjects is preparation of modified electrodes with a high specific surface area as well as fast response characteristics. In this study, novel bismuth oxide surface-decorated nanoporous bismuth (Bi2O3@NPBi) was prepared through a typical dealloying method, where a bicontinuous ligament–channel structure greatly improved the electrically active surface area and electron conduction. The Bi2O3@NPBi-modified electrode was employed to detect heavy metal ions using square wave anodic stripping voltammetry (SWASV), and the corresponding limits of detection (LOD) were 0.02 and 0.03 µg/L for simultaneous detection of Pb2+ and Cd2+. Due to the high cycling stability and capacity of bismuth oxides, the relative standard deviation (RSD) of the response currents using Bi2O3@NPBi was less than 4.16%, which is very considerably lower than the RSD of NPBi. Furthermore, a Bi2O3@NPBi-modified electrode was used to determine the concentration of Pb2+ and Cd2+ in tap water samples, and excellent recovery figures were obtained as there is little interference from other co-existing ions. In conclusion, the Bi2O3@NPBi-modified electrode showed good reusability and feasibility for quality assurance in agricultural, food and environmental applications.

Simultaneous, Selective and Highly Sensitive Voltammetric Determination of Lead, Cadmium, and Zinc via Modified Pencil Graphite Electrodes

AbstractPencil graphite electrode (PGE) modified with MWCNT and Bi3+ (MWCNT/Bi/PGE) was utilized in simultaneous analysis of Pb2+, Cd2+, and Zn2+. Surface and electrochemical characteristics of MWCNT/Bi/PGE were investigated via SEM, cyclic voltammetry, electrochemical impedance spectroscopy, and FTIR measurements. Even though modification with MWCNT did not improve the electroactive surface area, it significantly decreased the charge transfer resistance. Furthermore, modification with Bi3+ significantly increased the sensitivity. Finally, MWCNT/Bi/PGE exhibited the highest sensitivity and reproducibility compared to PGE and PGE modified with only MWCNT. MWCNT/Bi/PGE provided LOD values of 0.27, 0.43, and 1.63 μg L−1, and linear ranges of 1–80, 5–80, and 10–80 μg L−1 for Pb2+, Cd2+, and Zn2+, respectively. Proposed modification method offers effective electroanalytical performance with low time consumption and cost for the analyst.

Comparison Studies on Several Ligands Used in Determination of Cd(II) in Rice by Flame Atomic Absorption Spectrometry after Ultrasound-Assisted Dispersive Liquid-Liquid Microextraction.

Ligands plays an important role in the extraction procedures for the determination of cadmium in rice samples by using flame atomic absorption spectrometry (FAAS). In the present study, comparative evaluation of 10 commercially available ligands for formation of Cd(II)-ligand complex and determination of cadmium in rice samples by ultrasound-assisted dispersive liquid–liquid microextraction (UADLLME) combined with FAAS was developed. Sodium diethyldithiocarbamate (DDTC) provided a high distribution coefficient as well as a good absorbance signal, therefore DDTC was used as a ligand in UADLLME. A low density and less toxic solvent, 1-heptanol, was used as the extraction solvent and ethanol was used as the disperser solvent. In addition, the experimental conditions of UADLLME were optimized in standard solution first and then applied in rice, such as the type and volume of extractant and dispersant, pH, extraction time, and temperature. Under the optimal experimental conditions, the detection limit (3σ) was 0.69 μg/L for Cd(II). The proposed method was applied for the determination of Cd(II) in three different rice samples (polished rice, brown rice, and glutinous rice), the recovery test was carried out, and the results ranged between 96.7 to 113.6%. The proposed method has the advantages of simplicity, low cost, and accurate and was successfully applied to analyze Cd(II) in rice.

A Comprehensive Analytical Chemistry Experiment Oriented to the Entire Analysis Process: Determination of Cadmium in Rice by Graphite Furnace Atomic Absorption Spectrometry

A Comprehensive Analytical Chemistry Experiment Oriented to the Entire Analysis Process: Determination of Cadmium in Rice by Graphite Furnace Atomic Absorption Spectrometry

Development of 2-aminobenzoic Acid as a Complexing Ligand for Simultaneous Adsorptive Cathodic Stripping Voltammetric Determination of Trace Copper, Lead and Cadmium

Development of 2-aminobenzoic Acid as a Complexing Ligand for Simultaneous Adsorptive Cathodic Stripping Voltammetric Determination of Trace Copper, Lead and Cadmium

Chelating Resin Based on Silica Gel for Solid-Phase Extraction Coupled with Flame Atomic Absorption Spectrometric Determination of Nickel and Cadmium

Chelating resins offer a fast, accurate and simple method for separation and preconcentration of metal ions at low concentrations prior to their determination by an instrumental method. Silica gel-based chelating resin with chemically immobilized aurintricarboxylic acid was synthesized, characterized and used to determine Ni(II) and Cd(II) at trace levels, coupled with their analysis by flame atomic absorption spectrometer. The resin had sorption capacities of 0.21 mmol g-1 and 0.10 mmol g-1 for Ni(II) and Cd(II), respectively. The analytical detection limit (N = 20) was 1.70 μg L-1 for Ni(II) and 1.90 μg L-1 for Cd(II). The proposed method was useful for the quantitative determination of Ni(II) and Cd(II) in some commercial and water samples.

Introducing an interesting and novel strategy based on exploiting first-order advantage from spectrofluorimetric data for monitoring three toxic metals in living cells

In this work, we did our best to develop a novel and interesting analytical method based on coupling of spectrofluorimetry with first-order multivariate calibration techniques for simultaneous determination of lead (Pd), zinc (Zn) and cadmium (Cd) in HeLa cells. To achieve this goal, quenching of the emission of graphene (GR) was individually investigated in the presence of Pb, Zn and Cd and then, according to the linear ranges obtained from individual calibration graphs, a multivariate calibration model was developed based on modeling of the quenching of the emission of GR in the presence of the mixtures of Pb, Zn and Cd. First-order multivariate calibration models were constructed by partial least squares (PLS), principal component regression (PCR), orthogonal signal correction-PLS (OSC-PLS), continuum power regression (CPR), robust continuum regression (RCR) and partial robust M-regression (PRM) and their performances were evaluated and statistically compared. Finally, the OSC-PLS was chosen as the best model with the best practical performance for analytical purposes.