Inductively Coupled Mass Spectrometer Research Articles

Determination of Some Element’s Migrants in Aqueous Simulant from Plastic Food Contact Products by Inductively Coupled Plasma Mass Spectrometer

AbstractVarious chemicals present at different stages in the food supply chain can lead to the leaching of heavy metals. These metals can accumulate in the human body through the consumption of contaminated food. Consequently, it is necessary to validate an analytical technique for the quantification chemical that could contaminate food. This study presents a rapid, straightforward, and efficient analytical method for the direct quantification of some potentially toxic elements in aqueous simulants from plastic food contact products using an inductively coupled mass spectrometer (ICP-MS). The method’s validation encompassed the study of the estimated detection limits, practical quantification limits, linearity, accuracy, and measurement uncertainty of aluminium (Al), antimony (Sb), arsenic (As), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), lead (Pb), manganese (Mn), nickel (Ni), and zinc (Zn) under optimized ICP-MS conditions. The estimated detection limits ranged from 7.5 × 10−4 to 0.074 mg/kg, while practical quantification limits spanned from 0.02 to 0.8 mg/kg. The average recoveries ± standard deviations at different spiking levels were varied between 85.7 ± 1.51 and 115.6 ± 0.88% with coefficients of variation between 0.42 and 5.85%. The method trueness was verified by using references materials (test material in aqueous acetic acid) purchased from Food Chemistry Proficiency Testing and Analysis (FAPAS) yielding satisfactory results within acceptable recovery and Z-score values. The method precision, in terms of relative standard deviation (RSD), was being below 4.22%. The method uncertainty expressed as expanded uncertainty of all validated elements was found to be ≤ 21.9%. Validated method was employed to determine specific elements in aqueous simulants of thirty commercial plastic food packaging samples, representing three distinct types of plastic polymers. The results showed that the mean concentrations, in mg/kg, were as follows: 2.04 (Al), 0.02 (As), 0.02 (Cd), 0.02 (Co), 0.06 (Cr), 0.41 (Cu), 1.55 (Fe), 0.09 (Mn), 0.15 (Ni), 0.07 (Pb), 0.05 (Sb), and 0.81 (Zn). Furthermore, 30% of analyzed samples exceeding the maximum permissible limits of Al for plastic materials and articles intended to come into contact with food.

Development and validation of a simple microwave-assisted digestion sample preparation technique for the estimation of aluminium and magnesium in a few pharmaceutical dosage forms by an inductively coupled-mass spectrometer (ICP-MS).

Rationale: A simple, sensitive, reliable, validated, inductively coupled plasma mass spectrometric method for the determination of aluminium and magnesium using a simple common microwave-assisted digestion sample preparation technique for a few commonly used formulations was developed and validated according to International Conference on Harmonization Q3D and the United States Pharmacopeia general chapter <232> and <233>. The following pharmaceutical dosage forms were considered for estimation of aluminium and magnesium: Alumina, magnesia simethicone oral suspension, Alumina, magnesia simethicone chewable tablets, alumina and magnesia oral suspension, alumina and magnesium carbonate oral suspension. Methods: The methodology included optimizing a common microwave assisted digestion method, selecting the isotopes, choosing the measurement technique, and designating internal standards. The finalized microwave assisted procedure was a two-step program where in the first step the samples were ramped for 10 min to a temperature of 180 °C and hold for 5 min followed by ramping for 10 min to a temperature of 200 °C and hold for 10 min. Magnesium (24Mg) and aluminium (27Al) isotopes were finalized, internal standard assigned for both the isotopes was yttrium (89Y) with Helium (kinetic energy discrimination-KED) as the measuring mode. System suitability was run before initiating analysis to ensure that system performance was consistent. Results: Analytical validation parameters like specificity, linearity (from 25% to 200% of sample concentration), the detection limit and the limit of quantification were established. For all these dosage forms, the method's precision was demonstrated by analyzing the percentage relative standard deviation for six injections. Accuracy was established from 50% to 150% of instrument working concentration (J-levels) for aluminium and magnesium for all the formulations and was found to be within the range of 90-120%. Conclusion: This common analysis method, along with the common microwave-digestion technique applies to numerous types of matrices for a finished dosage form with aluminium and magnesium.

Association between cadmium exposure and pulmonary function reduction: Potential mediating role of telomere attrition in chronic obstructive pulmonary disease patients

BackgroundEnvironmental cadmium (Cd) exposure is linked to pulmonary function injury in the general population. But, the association between blood Cd concentration and pulmonary function has not been investigated thoroughly in chronic obstructive pulmonary disease (COPD) patients, and the potential mechanisms are unclear. MethodsAll eligible 789 COPD patients were enrolled from Anhui COPD cohort. Blood specimens and clinical information were collected. Pulmonary function test was conducted. The subunit of telomerase, telomerase reverse transcriptase (TERT), was determined through enzyme linked immunosorbent assay (ELISA). Blood Cd was measured via inductively coupled-mass spectrometer (ICP-MS). ResultsBlood Cd was negatively and dose-dependently associated with pulmonary function. Each 1-unit increase of blood Cd was associated with 0.861 L decline in FVC, 0.648 L decline in FEV1, 5.938 % decline in FEV1/FVC %, and 22.098 % decline in FEV1 % among COPD patients, respectively. Age, current-smoking, self-cooking and higher smoking amount aggravated Cd-evoked pulmonary function decrease. Additionally, there was an inversely dose-response association between Cd concentration and TERT in COPD patients. Elevated TERT obviously mediated 29.53 %, 37.50 % and 19.48 % of Cd-evoked FVC, FEV1, and FEV1 % declines in COPD patients, respectively. ConclusionBlood Cd concentration is strongly associated with the decline of pulmonary function and telomerase activity among COPD patients. Telomere attrition partially mediates Cd-induced pulmonary function decline, suggesting an underlying mechanistic role of telomere attrition in pulmonary function decline from Cd exposure in COPD patients.

Arsenic Metabolism, Toxicity and Accumulation in the White Button Mushroom Agaricus bisporus.

Mushrooms have unique properties in arsenic metabolism. In many commercial and wild-grown mushrooms, arsenobetaine (AsB), a non-toxic arsenical, was found as the dominant arsenic species. The AsB biosynthesis remains unknown, so we designed experiments to study conditions for AsB formation in the white button mushroom, Agaricus bisporus. The mushrooms were treated with various arsenic species including arsenite (As(III)), arsenate (As(V)), methylarsenate (MAs(V)), dimethylarsenate (DMAs(V)) and trimethylarsine oxide (TMAsO), and their accumulation and metabolism were determined using inductively coupled mass spectrometer (ICP-MS) and high-pressure liquid chromatography coupled with ICP-MS (HPLC-ICP-MS), respectively. Our results showed that mycelia have a higher accumulation for inorganic arsenicals while fruiting bodies showed higher accumulation for methylated arsenic species. Two major arsenic metabolites were produced in fruiting bodies: DMAs(V) and AsB. Among tested arsenicals, only MAs(V) was methylated to DMAs(V). Surprisingly, AsB was only detected as the major arsenic product when TMAsO was supplied. Additionally, AsB was only detected in the fruiting body, but not mycelium, suggesting that methylated products were transported to the fruiting body for arsenobetaine formation. Overall, our results support that methylation and AsB formation are two connected pathways where trimethylated arsenic is the optimal precursor for AsB formation.

Potential human health risk assessment of potentially toxic elements intake via consumption of soft drinks purchased from different Egyptian markets

ABSTRACT Consumption of soft drinks with high potentially toxic elements concentrations may lead to acute or chronic poisoning. Soft drinks have been shown to contain traces of some potentially toxic elements such as cadmium, lead, mercury arsenic, zinc, etc. which may be due to environmental pollution from the surface and underground water, food and fruits utilised during production, and can be toxic for humans. In this study, Quadrupole Inductively Coupled Mass Spectrometer (Q-ICP-MS) was used in a simple validated method of analysis for direct determination of Al, Sb, As, Cd, Cr, Co, Cu, Fe, Pb, Mn, Hg, Ni, Sn, and Zn in soft drink samples. Analysis of 130 samples covering 14 different brands of popular soft drinks in Egypt to assess whether the intakes complied with the upper permissible levels for tested metals was performed. The results showed that all analysed samples were free from any detectable amount of Hg, while the mean concentrations, in µg/L, were as follows: 1.48 (Cr), 1.96 (As), 0.77 (Sb), 0.53 (Co), 20.27 (Mn), 108.83 (Fe), 0.52 (Cd), 13.18 (Cu), 8.55 (Ni), 20.00 (Sn), 80.09 (Al), 36.54 (Zn), and 1.05 (Pb). The health risk assessment was evaluated for estimated weekly intake, the hazard quotient, the hazard index and the target cancer risk using the Food and Nutrition Board, FAO/WHO and USEPA recommendations. The weekly intakes of all elements were found to be significantly below the recommended tolerable levels. Also, the hazard quotient, the hazard index and the target cancer values for all elements were found to be lower than acceptable guideline values, which indicated that there was no any non-carcinogenic or carcinogenic effects may occur.

Stability Investigations of Platinum Electrodes in Nonaqueous Systems

Fundamental understanding of electrode dissolution processes in nonaqueous media is crucial for applications like nonaqueous battery systems, sensors, capacitors but also organic electrochemistry and is inextricably related to economic considerations. The reasons for electrode degradation are among others anodic dissolution, cathodic dissolution or cathodic corrosion. Enhanced knowledge of dissolution mechanisms and factors like composition or structure of electrodes, electrolyte and temperature are important to optimize the operation conditions, limit electrode degradation and increase the lifetime of devices.The development of the scanning flow cell (SFC) combined with an Inductively Coupled Mass Spectrometer (ICP-MS), allowing online stability studies, has given valuable insights into degradation mechanisms of different electrodes and catalyst materials in aqueous media which are relevant for applications like fuel cells and electrolyzers. We have developed an electrochemical flow cell (EFC) coupled to the ICP-MS which is suitable for the use in aggressive nonaqueous electrolytes. The flow cell is operated in an argon filled glovebox which allows us to conduct electrochemical experiments in completely inert atmosphere under the exclusion of oxygen and water.Platinum is one of the most extensively studied electrode materials due to its excellent electrocatalytic activity and inertness in various applications. Our novel method allows new insights into the complex behavior of platinum in nonaqueous electrolytes, among others in its dissolution. New aspects regarding the stability of platinum in different nonaqueous electrolytes are unveiled depending on the chemical properties of the solvent and the conducting salt. While the dissolution behavior of completely water free protic electrolytes like methanol and aprotic electrolytes like acetonitrile is very similar, the dissolution behavior changes completely in presence of trace amounts of water. Furthermore, different cations and anions in the electrolyte effect the anodic dissolution and cathodic corrosion, respectively.The controlled addition of water to nonaqueous electrolytes is an important tool to study the behavior of the formation and dissolution of the platinum oxide passivation layer and is not only relevant for nonaqueous electrocatalysis but also gives new insights into the dissolution mechanisms in aqueous electrolytes.The details of the method and different platinum dissolution profiles in several nonaqueous electrolytes will be discussed. Additionally, dissolution mechanisms will be proposed based on studies with changing water content.

Fine Tuning of the Oxygen Evolution Reaction Activity and Stability of Hydrous Iridium Oxides By Thermal Treatment

In the future energy concept renewable wind and solar energy will play the dominating role. It is anticipated that due to the intermittent nature of power outcome from the renewable energy sources, there will be an energy surplus which can be efficiently stored. As an example hydrogen could be successfully produced by proton exchange membrane water electrolysis (PEM-WE). Alternatively carbon dioxide could be converted to a valuable product in an electrochemical reduction process. Up to now the oxygen evolution reaction (OER) will be the counter reaction for hydrogen evolution as well as CO2 reduction. Nowadays iridium is the main component of the anode catalyst in PEM-electrolysers since it shows the best performance in terms of activity and stability [1]. Due to the high price and scarcity of iridium, however, the goal for the near future is a better utilization and partial or complete replacement of this precious metal. Since no alternative with comparable performance is in the sight, current research efforts are directed towards increase in surface to mass ratio and specific activity of iridium catalysts. This can be achieved using nanoparticulated, highly porous materials [2]. Furthermore, introduction and leaching of a less noble metal [3] or tuning of the oxide structure, e.g. by varying calcination temperature should be considered [4, 5]. In this study a scanning flow cell (SFC) combined with an inductively coupled mass spectrometer (ICP-MS) is used to obtain synchronized time- and potential-resolved data on the OER-activity and dissolution of iridium electrodes [5, 6]. This should shed some light onto the stability of different kinds of iridium oxides used in literature by utilizing a model sputtered iridium film. The examined materials are iridium (hydrous)-oxides prepared electrochemically and treated thermally in the temperature range of 100 – 600 °C. X-ray photoelectron spectroscopy (XPS) is used to correlate the electrochemical behaviour with the surface composition. The obtained information on the electrocatalytic activity and stability together with data on the electrodes physicochemical properties and their temperature dependence are used in the discussion of OER mechanism on iridium oxide electrodes.

Heavy Metal Concentration in the Soil and Sediment of Kotur Industrial Area Hyderabad, India

Heavy metal accumulations in the environment are major sources of pollution and contamination. Soil samples were collected from Kotur industrial area and analysed for heavy metal concentration such as Vanadium, Chromium, Nickel, Cobalt, Copper, Zinc, Barium, Lead, Rubidium, Strontium, and Zircon using inductively coupled mass spectrometer (ICP-MS) instrument. The ranges of concentration obtained for these metals are V (60.96-111 mg/kg), Cr (68.22–141.03 mg/kg), Ni (33.18-68.74 mg/kg), Co (10.16-17.67 mg/kg), Cu (26.35-47.59 mg/kg), Zn (49.95-183.23 mg/kg) and Pb (30.98-79.91 mg/kg). The analytical data revealed concentration above the background values. The assessment of the contamination level of the area was based on geoacummulation index (Igeo), enrichment factor (EF) and anthropogenic input. The result also showed enrichment associated with anthropogenic input for the heavy metals such as Cr, Ni, Pb, and Cu in the study area. The calculated Igeo values ranges from 1.19 to 1.43. The EF values for Cr, Ni and Pb range from 0.80 to 3.08, 0.68 to 3.07 and 0.82 to 20.6 respectively indicating moderate enrichment. The coefficient values of 0.90, 0.66, 0.62 and 0.58 observed between V and Co, Cu and between Pb with Y and Zr indicate input from similar sources. Original Research Article Okoyeh et al.; JSRR, 6(2):124-132, 2015; Article no.JSRR.2015.137 125

The effect of different growing area on the Cu, Mn and Zn content of winter wheat

In this study the Cu, Mn and Zn content of winter wheat ( Triticum aestivum L.) grains were investigated. Plant samples were collected from 2004 when the weather was very wet. Samples were harvested from five experimental stations of the Hungarian national long-term fertilization trials. These are the following: Bicserd, Iregszemcse, Karcag, Nagyhorcsok and Putnok. These experimental fields have different soil types and climatic conditions. The element content of samples were measured using inductively coupled plasma optical emission spectrometer (ICP-OES) and inductively coupled mass spectrometer (ICP-MS) following digestion with HNO 3 -H 2 O 2 solution. Data analysis was performed using SPSS for Windows 13.0 Software package. All data were subjected to ANOVA, and when significant differences (P<0,05) were detected, Duncan’s test was performed to allow separation of means. The test results proved that the different regions caused significant (P <0.01) difference in the element content of winter wheat samples.

Complementary FPLC-ICP-MS and MALDI-TOF for studying vanadium association to human serum proteins

The on-line coupling of fast protein liquid chromatography (FPLC) with an inductively coupled mass spectrometer (ICP-MS), with and without collision cell system, has been evaluated for studying vanadium association to human serum proteins. The separation of human serum proteins was achieved on a MonoQ (HR5/5) anion-exchange column using an ammonium acetate gradient (0–0.5 mol l−1) in the mobile phase. Proteins, initially incubated with V(III) or alternatively V(IV), were detected spectrophotometrically at 295 nm and the V detection was carried out on-line with a quadrupole ICP-MS (ICP-Q-MS) or an octopole ICP-MS collision/reaction cell (ICP-ORS-MS) system. In such an arrangement, both instruments proved to be adequate for V detection at basal levels in human serum. The results obtained with the procedure developed confirmed that V(IV) as well as V(III) seem to be eventually associated preferentially to transferrin protein in normal human serum. The observed vanadium distribution profile is similar to that previously reported for Fe(III) and Al(III) associations to human serum transferrin. Intact protein analysis by MALDI-TOF has confirmed the molecular structure of transferrin as the protein associated to the V fraction.