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Rationale: Bromine and iodine have important physiological functions; however, in inadequate concentration, they can also cause several physiological problems. Their mobility assessment in human organisms through biological sampling may help clarify some doubts related to metabolic routes, which are still not well elucidated. In this context, a suitable analytical method for this purpose should be developed., Methods: An analytical method for determining ultratrace levels of bromine and iodine in human nail samples was developed. Inductively coupled plasma mass spectrometry (ICP-MS) using a conventional nebulization system was immediately chosen as the determination tool because of its powerful sensitivity and selectivity. Sample preparation methods including microwave-induced combustion (MIC), microwave-assisted extraction, and microwave-assisted digestion were evaluated. The compatibility of the final solutions with ICP-MS analysis was considered while the method was developed., Results: MIC was chosen as the most suitable method for the sample preparation for determining the levels of bromine and iodine in human nail samples using ICP-MS. Unlike other sample preparation methods, this one fully eliminated interferences related to the carbon content and memory effects. Sample masses up to 100 mg were efficiently digested, and the analytes were quantitatively absorbed using only 50 mmol L -1 NH 4 OH solution. Recoveries ranged from 93% to 102%, and the relative standard deviation was < 8%., Conclusions: The proposed analytical method presents important characteristics for routine analysis. It allows ultratrace determination even when low sample masses are used because of the low blank values, reduced volume of reagents, and powerful detectability using ICP-MS., (© 2019 John Wiley & Sons, Ltd.)

Rationale: To increase the consumption of egg powder and its fractions a suitable quality control method is required to obtain more information on its nutritional composition. The proposed method enables the quantification of important elements for the functioning of the human organism, such as halogens and sulfur, in egg powder and its fractions., Methods: Up to 350 mg of egg powder or its fractions (egg white powder and egg yolk powder) were digested by microwave-induced combustion using 20 bar pressure of oxygen. The analytes were absorbed in 100 mmol L -1 of NH 4 OH solution. The determination of halogens (chlorine, bromine, fluorine, and iodine) and sulfur was performed in a single analysis using ion chromatography with conductivity detection coupled to mass spectrometry., Results: Using the proposed method, spike recoveries between 99% and 104% for all analytes were obtained, and results agreed with certified values of reference materials (agreements were between 100% and 109%). The relative standard deviations were below 8%. The variation in elemental concentration over a wide range in different fractions (whole egg powder, egg white powder, and egg yolk powder) and different brands was also observed., Conclusions: The proposed method provides reliable information about minerals in whole egg powder and its fractions, contributing to better quality control of these products. Because these food products are widely consumed, these results suggest the safe ingestion levels of these elements., (© 2020 John Wiley & Sons, Ltd.)

A single analysis of hair for determining halogens (chlorine, bromine, fluorine, and iodine) and sulfur by ion chromatography with suppressed conductivity and mass spectrometry detection (IC-MS) was proposed. Inductively coupled plasma optical emission spectrometry (ICP OES) and inductively coupled plasma mass spectrometry (ICP-MS) were also used to compare the results. For this purpose, 300 mg of human hair were digested by microwave-induced combustion (MIC) using 20 bar of oxygen pressure. The analytes were absorbed in 100 mmol L -1 NH 4 OH. Trueness of the proposed method was evaluated by analysis of a CRM of human hair; by recovery tests, using standard solution at two levels (50% and 100%), and by comparison of results with those obtained by ICP OES (Cl and S) and ICP-MS (Br and I). Suitable recoveries (ranging from 92 to 105%) were obtained, and the results from CRM analysis did not differ significantly from those described in the certificate. Moreover, results obtained by IC-MS did not present significant differences (p > 0.05) from those obtained by ICP OES and by ICP-MS. Precision was evaluated in terms of repeatability and intermediate precision, and the relative standard deviations were always lower than 8%. The proposed method presented good accuracy and it is a reliable strategy for human hair analysis. Final digests obtained using the MIC method were fully compatible with all proposed determination techniques. Compared to others reported in the literature, the proposed method presents several advantages, especially given that it is possible to determine halogens and sulfur in a single analysis. Graphical abstract.

Responding to the need for green and efficient methods to determine catalyst residues with suitable precision and accuracy in samples with high fat content, the present work evaluates a microwave-assisted ultraviolet digestion (MW-UV) system for margarines and subsequent determination of Ni, Pd and Pt using inductively coupled plasma mass spectrometry (ICP-MS). It was possible to digest up to 500mg of margarine using only 10mL of 4molL -1 HNO 3 with a digestion efficiency higher than 98%. This allowed the determination of catalyst residues using the ICP-MS and free of interferences. For this purpose, the following experimental parameters were evaluated: concentration of digestion solution, sample mass and microwave irradiation program. The residual carbon content was used as a parameter to evaluate the efficiency of digestion and to select the most suitable experimental conditions. The accuracy evaluation was performed by recovery tests using a standard solution and certified reference material, and recoveries ranging from 94% to 99% were obtained for all analytes. The limits of detection for Ni, Pd and Pt using the proposed method were 35.6, 0.264 and 0.302ngg -1 , respectively. When compared to microwave-assisted digestion (MW-AD) in closed vessels using concentrated HNO 3 (used as a reference method for sample digestion), the proposed MW-UV could be considered an excellent alternative for the digestion of margarine, as this method requires only a diluted nitric acid solution for efficient digestion. In addition, MW-UV provides appropriate solutions for further ICP-MS determination with suitable precision (relative standard deviation < 7%) and accuracy for all evaluated analytes. The proposed method was applied to margarines from different brands produced in Brazil, and the concentration of catalyst residues was in agreement with the current legislation or recommendations., (Copyright © 2017 Elsevier B.V. All rights reserved.)

A method for Br and I determination in whole egg powder and its fractions (egg white and yolk) was developed by combining microwave-induced combustion (MIC) and inductively coupled plasma mass spectrometry (ICP-MS). Using the MIC method, 350mg of whole egg powder and its fractions were efficiently digested using 50mmolL -1 NH 4 OH as an absorbing solution. The limits of detection for Br and I using the MIC method followed by ICP-MS determination were 0.039 and 0.015μgg -1 , respectively. Using the proposed method, agreements with the reference values between 97 and 104% for Br and I were obtained by analysis of reference material NIST 8435. Finally, it was possible to observe that Br concentration (4.59-5.29μgg -1 ) was higher than I (0.150-2.28μgg -1 ) for all the evaluated samples., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

This document is a summary of an article titled "Elemental Mass Spectrometry for Bioanalysis" published in the journal Analytical & Bioanalytical Chemistry. The article discusses the importance and versatility of mass spectrometry (MS) as an analytical tool for characterizing matter in living and non-living systems. It focuses on elemental mass spectrometry, which involves degrading matter to its basic components, and highlights the use of inductively coupled plasma mass spectrometry (ICP-MS) as a primary source for elemental ions. The article also covers various applications of elemental mass spectrometry in fields such as environmental monitoring, food control, and biological research. The topical collection in the article includes 24 contributions that reflect current research and trends in elemental mass spectrometry for bioanalysis, covering topics such as sample preparation, elemental speciation, protein analysis, and the detection of small objects like cells and nanoparticles. The guest editors express their appreciation for the contributions and hope that the collection serves as a valuable source for readers. The article is authored by Jörg Bettmer, Mario Corte-Rodríguez, and Marcia Foster Mesko, who are experts in the field of analytical chemistry and have published extensively in this area. [Extracted from the article]