scholarly journals Determination of Arsenic, Chromium and Lead in titanium dioxide pigments by ICP- OES with Concomitant Metals Analyser

2019 ◽  
pp. 296-305
Author(s):  
Beena Sunilkumar ◽  
S. B. Singh
Keyword(s):  
Titanium Dioxide ◽  
Matrix Effects ◽  
Mineral Acid ◽  
Icp Oes ◽  
Acid Decomposition ◽  
Simple Method ◽  
Sample Dissolution ◽  
The Matrix ◽  
Generating System

A simple method has been developed for the determination of trace toxic elements like arsenic, lead and chromium in titanium dioxide pigment samples by ICP OES attached with a Concomitant Metals Analyser. Open mineral acid decomposition was used for sample dissolution employing a mixture of nitric and hydrofluoric acids. The continuous online generation of hydrides into the plasma was achieved through a concomitant metals analyser. The recovery of arsenic, lead and chromium and the matrix effects of titanium on these elements have been studied with spiking experiments. The proposed method has been successfully applied to the determination of arsenic and other elements in titanium pigment samples. The continuous hydride generating system, Concomitant Metals Analyser (CMA) improved the sensitivity of analysis nearly five times in pigment samples. The precision of the measurements was found to be less than 10% RSD.

Determination of 22 trace elements in high-purity copper including Se and Te by ETV-ICP OES using SF6, NF3, CF4and H2as chemical modifiers

2016 ◽  
Vol 31 (3) ◽  
pp. 642-657 ◽  
Author(s):  
J. Hassler ◽  
R. Matschat ◽  
S. Richter ◽  
P. Barth ◽  
A. K. Detcheva ◽  
...  
Keyword(s):  
Trace Elements ◽  
High Purity ◽  
Icp Oes ◽  
Chemical Modifiers ◽  
The Matrix ◽  
Scope Of Application ◽  
Pre Treatment ◽  
Purity Copper

Experiments with SF6, NF3, CF4and H2as new modifier gases for the matrix studied were performed. Pre-treatment steps of sub-samples (e.g., roasting) can now be omitted; the scope of application was enlarged to Au and hydride forming elements (such as Se, Te).

Detection Confirmation and Determination of Trace Amounts of Selenium by X-Ray Methods

1963 ◽  
Vol 7 ◽  
pp. 542-554
Author(s):  
Frank L. Chan
Keyword(s):  
Matrix Effects ◽  
Hexagonal Structure ◽  
Elemental Selenium ◽  
X Ray Diffraction ◽  
X Ray ◽  
Yellow Color ◽  
The Matrix ◽  
Ray Methods ◽  
Tetravalent State

AbstractRecently, interest in the determination of selenium in trace amounts has been greatly intensified because of the nutritional aspects of this element. It has been reported that selenium in the amount of 13 μg in the form of sodium selenite in 100 g of feed has an effect similar to that of vitamin E. In the field of semiconductors, the detection and determination of trace amounts of selenium in arsenic, antimony, and small single crystals of solid solution of cadmium selenide and sulfide are of considerable importance in semiconductor performance.In the Aerospace Research Laboratories, 4,5 diamino-6-tbiopyi-imidine has been successfully adopted as a reagent for the spectrophotometric determination of selenium. The reaction of 4,5 diamino-6-thiopyrimidine and tetxavalent selenium produces a yellow color with the formation of elemental selenium. It is possible to determine elemental selenium by collecting it in a thin layer. The selenium deposited in this layer may then be determined by an X-ray fluorescence method. A procedure of this nature has the advantage of eliminating the matrix effects commonly encountered in X-ray fluorescence. Furthermore, the slow generation of selenium affords a convenient means of detection and confirmation of this element by the use of X-ray diffraction procedures. By this technique selenium is first converted to its tetravalent state and is then reacted with 4,5 diamino-6-thiopyrimidine. On standing, the selenium is reduced to a red precipitate of elemental selenium which can be dissolved in carbon disulfide. Finally, the selenium can be converted into its hexagonal structure by annealing at 205-207°C.

Molecularly Imprinted Solid-Phase Extraction for Chlorpyrifos Determination in Water Samples

2010 ◽  
Vol 113-116 ◽  
pp. 947-951 ◽  
Author(s):  
Jun Liu ◽  
Ming Yang ◽  
Lu Feng Huai
Keyword(s):  
Solid Phase Extraction ◽  
Water Samples ◽  
Matrix Effects ◽  
Solid Phase ◽  
Final Analysis ◽  
Sewage Water ◽  
Phase Extraction ◽  
Simple Method ◽  
Molecularly Imprinted ◽  
The Matrix

The determination of chlorpyrifos at low ngL-1 levels in wastewater requires highly selective and sensitive analytical procedures. The removal of matrix components during sample preparation results in significant benefits towards reducing the matrix effects during GC analysis. Therefore this work describes a simple method to enrich and clean up chlorpyrifos from sewage water using molecularly imprinted solid phase extraction (MISPE). Final analysis was performed by gas chromatography. The performance of this method has been evaluated in water samples in terms of recovery, precision, and method quantification limit. Recovery for chlorpyrifos ranged between 99 and 105% with RSD values below 7.9%. The performance of the method was further emphasized by the study of different water samples. In these samples, chlorpyrifos were detected in concentration above method quantification limits ranging from 50 to 3000 ngL-1.

scholarly journals Simultaneous Determination of Rimsulfuron and Haloxyfop-P-methyl and Its Metabolite Haloxyfop in Tobacco Leaf by LC-MS/MS

2019 ◽  
Vol 102 (5) ◽  
pp. 1632-1640
Author(s):  
Yurong Yu ◽  
Shan Zhao ◽  
Ya Yang ◽  
Ya Chen ◽  
Daimei Qiu ◽  
...  
Keyword(s):  
Simultaneous Determination ◽  
Weed Management ◽  
Matrix Effects ◽  
High Sensitivity ◽  
Tobacco Leaf ◽  
Extraction Solvent ◽  
Nicotiana Tabacum L ◽  
The Matrix ◽  
Pretreatment Conditions

Abstract Background: Tobacco (Nicotiana tabacum L.), is an important economic crop. In China, the use of rimsulfuron and haloxyfop-P-methyl herbicides for weed management during the planting period is necessary to improve the production of tobacco. Objective: To establish and validate a quick, easy, cheap, effective, rugged, and safe LC-MS/MS method to determine rimsulfuron, haloxyfop-P-methyl, and haloxyfop in tobacco leaf samples. Methods: We optimized MS/MS conditions and chromatographic conditions for optimal detection conditions. The extraction solvent and sorbent were optimized, and the analysis of variance was applied to analyze the pretreatment method to obtain the optimal pretreatment conditions. Results: The validation results showed that the proposed method exhibited good linearity (R2 > 0.9978), satisfactory recovery (72.51–101.60%) and low LOQ (0.02–1.00 mg/kg). The matrix effects of the three analytes in the two tobacco leaf matrixes were different. The dissipation results showed that the half-lives of rimsulfuron and haloxyfop-P-methyl in fresh tobacco leaf samples were ranged from 2.4 to 3.7 days. The final residues of rimsulfuron, haloxyfop-P-methyl, and haloxyfop in flue-cured tobacco leaf samples were all lower than the LOQ. Conclusions: The results demonstrate that the developed method could be used to detect rimsulfuron, haloxyfop-P-methyl, and haloxyfop in tobacco leaf matrixes. Highlights: A method for simultaneous determination of rimsulfuron, haloxyfop-P-methyl, and haloxyfop in tobacco leaf samples with high sensitivity has been established for the first time.

scholarly journals Determination of Impurities in Sintered Magnesia and Spinel by Pressure Acid Decomposition/ICP-OES

2007 ◽  
Vol 56 (8) ◽  
pp. 679-685 ◽  
Author(s):  
Yoshinori UWAMINO ◽  
Hisashi MORIKAWA ◽  
Akira TSUGE
Keyword(s):  
Icp Oes ◽  
Acid Decomposition ◽  
Determination Of Impurities

scholarly journals Development of a rapid UPLC-MS/MS method for the determination of toddalolactone in mouse blood and its application in pharmacokinetics

2021 ◽  
Author(s):  
Jing Zhou ◽  
Hongzhe Wang ◽  
Caiyun Miao ◽  
Yunxi Yao ◽  
Jianshe Ma
Keyword(s):  
Matrix Effects ◽  
Multiple Reaction Monitoring ◽  
Internal Standard ◽  
Absolute Bioavailability ◽  
Quantitative Detection ◽  
Ionization Source ◽  
Mouse Blood ◽  
The Matrix ◽  
Product Ions

AbstractA rapid and simple UPLC-MS/MS method was developed to determine toddalolactone in mouse blood and applied to measure the pharmacokinetics of toddalolactone in mice. Blood samples were first preprocessed by ethyl acetate liquid-liquid extraction. Oxypeucedanin hydrate (internal standard, IS) and toddalolactone were gradient eluted from a UPLC BEH C18 column using a mobile phase consisting of acetonitrile and water (0.1% formic acid). Using electrospray ionization (ESI) as the ionization source, multiple reaction monitoring was used to detect the precursor and product ions of m/z 309.2 and 205.2, respectively, for toddalolactone and of m/z 305.1 and 203.0 for IS, respectively, for quantitative detection. A calibration curve was run over the concentration range of 5–4,000 ng/mL (r > 0.995). The matrix effects ranged from 93.5 to 98.4%, and the recovery was higher than 77.3%. The precision was less than 13%, and the accuracy ranged from 90.9 to 108.4%. The developed UPLC-MS/MS method was successfully used for measuring the pharmacokinetics of toddalolactone in mice after oral (20 mg/kg) and intravenous administration (5 mg/kg), and the absolute bioavailability of toddalolactone was 22.4%.

scholarly journals Study on titanium dioxide nanoparticles as MALDI MS matrix for the determination of lipids in the brain

2021 ◽  
Vol 10 (1) ◽  
pp. 700-710
Author(s):  
Congnan Peng ◽  
Qian Zhang ◽  
Jian-an Liu ◽  
Zhen-peng Wang ◽  
Zhen-wen Zhao ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Titanium Dioxide ◽  
Titanium Dioxide Nanoparticles ◽  
Brain Homogenate ◽  
Maldi Ms ◽  
Absolute Ethanol ◽  
Future Research ◽  
Ionization Mass ◽  
The Matrix

Abstract The structures of lipids are diverse, and thus, lipids show various biological functions. Systematic determination of lipids in organisms has always been a concern. In this paper, a methodology on the matrix-assisted laser desorption ionization mass spectrometry (MALDI MS), with titanium dioxide nanoparticles (TiO2 NPs) as the matrix, was studied for lipid determination. The results showed that the following conditions were preferable in the determination of small-molecule lipids (such as hypoxanthine, guanosine, uridine, and cytidine), lipid standards (such as GC, GM, TG, phosphatidylethanolamine, phosphatidylcholine, and ceramide), and mixed lipids (extracted from brain homogenate with methanol alone and with the B&D method): TiO2 NPs as the matrix, absolute ethanol as the solvent, 1 mg of TiO2 NPs dispersed in 1 mL of absolute ethanol as the matrix solution, NaCl as the ionization reagent, and positive mass spectrometry (MS) as the mode. Modified TiO2 NP as a new matrix for MALDI MS will be a future research direction; in addition, the characteristics of TiO2 NPs make it a potential matrix for imaging MS.

scholarly journals Determination of non-cholesterol sterols in serum and HDL fraction by LC/MS-ms: Significance of matrix-related interferences

2019 ◽  
Vol 0 (0) ◽  
Author(s):  
Sandra Vladimirov ◽  
Tamara Gojkovic ◽  
Aleksandra Zeljkovic ◽  
Zorana Jelic-Ivanovic ◽  
Vesna Spasojevic-Kalimanovska
Keyword(s):  
Matrix Effect ◽  
Matrix Effects ◽  
Density Lipoprotein ◽  
Cholesterol Homeostasis ◽  
Cholesterol Concentration ◽  
Sample Type ◽  
Serum Samples ◽  
The Matrix ◽  
Simple Regression Analysis

Summary Background Non-cholesterol sterols (NCS) are promising biomarkers for estimation of cholesterol homeostasis properties. In addition, determination of NCS in high-density lipoprotein (HDL) fraction (HDL-NCS) could provide information on cholesterol efflux. However, matrix effects interfere in liquid chromatography–mass spectrometry (LC-MS) analysis of NCS, thereby impairing the method sensitivity. The aims of this study were development, optimization and validation of LC-MS method for quantification of NCS in serum and HDL-NCS. Additionally, matrix effect interferences and methods application in individual serum samples were examined. Methods HDL precipitating reagent was used for HDL isolation. Matrix effect was examined by comparing different surrogates by simple regression analysis. Validation was conducted according to the FDA-ICH guideline. 20 healthy volunteers were recruited for testing of method application. Results The observed matrix effect was 30%, and matrix comparison showed that cholesterol was the dominant contributor to the matrix effect. Cholesterol concentration was adjusted by construction of the calibration curve for serum and HDL fraction (5 mmol/L and 2.5 mmol/L, respectively). The intra- and inter- run variabilities for NCSs were 4.7–10.3% for serum NCS and 3.6–13.6% for HDL-NCS and 4.6–9.5% for serum NCSs and 2.5–9.8% for HDL-NCS, respectively. Recovery studies showed satisfactory results for NCSs: 89.8–113.1% for serum NCS and 85.3–95.8% for HDL-NCS. Conclusions The method was successfully developed and optimized. The matrix interference was solved by customising calibration curves for each method and sample type. The measurement of NCS in HDL fraction was proposed for the first time as potentially useful procedure in biomedical researches.

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