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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.)

An effective analytical method for bromine and iodine determination in human hair using interference-free inductively coupled plasma mass spectrometry (ICP-MS) was developed. Human hair was digested based on combustion reaction to obtain compatible solutions with ICP-MS analysis. Using microwave-induced combustion (MIC), masses of human hair ranging from 50 to 300 mg were efficiently digested. Only a diluted alkaline solution (100 mmol L -1  NH 4 OH) was used for the absorption of both analytes, which was fully compatible with ICP-MS analysis. Using these conditions low limits of detection were obtained (LOD of 0.01 μg g -1 for Br and 0.004 μg g -1 for I). Recovery tests at two levels (50% and 100%) using a standard solution or mixtures of the sample with certified reference materials (CRMs) were carried out to evaluate the suitability of proposed method and recoveries between 94% and 102% were always obtained. Accuracy was evaluated by analysis of a human hair CRM, and the Br and I concentrations obtained by the proposed method did not differ significantly from those described in the certificate. Repeatability (RSDs ≤ 4%) and reproducibility (RSDs ≤ 7%) of the results using proposed method were always very suitable. The digests obtained using the MIC method were fully compatible with ICP-MS and the interferences currently found using conventional digestion methods were completely eliminated. Ultra-trace concentrations of Br and I were determined in human hair, demonstrating that the proposed method is a suitable strategy, and it presents several advantages compared to others published in the literature., (Copyright © 2019 Elsevier B.V. All rights reserved.)

In this work, an analytical method for bromine and iodine determination in human saliva was proposed. A simple protocol based on centrifugation and direct analysis of supernatant by inductively coupled plasma mass spectrometry (ICP-MS) was investigated. Although this method was feasible for bromine determination, iodine was partially present in the supernatant and an agreement about 54% with reference value was obtained. In addition, microwave-induced combustion (MIC) and microwave-assisted dissolution were also evaluated. Using MIC, 0.2 mL of saliva added on 300 mg of microcrystalline cellulose were efficiently digested. A diluted solution (50 mmol L -1 NH 4 OH) was used for analytes absorption, and a reflux step of 5 min was applied to ensure quantitative recoveries of Br and I. Accuracy was evaluated by analyte recovery experiments, and recoveries between 94% and 98% were obtained. Microwave-assisted dissolution was evaluated for 2.0 mL of saliva using also a diluted alkaline solution (25 mmol L -1 NH 4 OH) and a microwave irradiation program of 35 min (including the cooling step). Results for this method agreed with those obtained using MIC. Although MIC has also been appropriated for further determination of Br and I in saliva, microwave-assisted dissolution can be considered a simpler sample preparation method and it was effective for high amount of sample (up to 2.0 mL). Moreover, final solutions were compatible with ICP-MS analysis, allowing the quantification of Br and I in human saliva at ultra-trace concentrations (limits of quantification were 0.052 μg mL -1 for Br and 0.022 μg mL -1 for I)., (Copyright © 2018 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.)

Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) was applied for the determination of Br and I in hair strands of human individuals under treatment with synthetic thyroid hormones. Quantification relied on the use of Br- and I-spiked human hair strands prepared in-house as matrix-matched external calibration standards. The results obtained via LA-ICP-MS agreed with the corresponding Br and I concentrations as determined via pneumatic nebulization-ICP-MS after digestion via microwave-induced combustion. The spatial distributions of Br and I in the spiked hair standards were evaluated by spatially resolved LA-ICP-MS analysis and a homogeneous distribution was established upon scanning longitudinally along the hair strands and across the cross-section. Twenty-five human hair strands from volunteers were analyzed by LA-ICP-MS (7 individuals with hypothyroidism under treatment with synthetic thyroid hormones and 18 individuals considered healthy), and those from subjects under treatment with synthetic thyroid hormones presented a higher I concentration than those from subjects considered healthy. Limits of detection were 0.36 μg g−1 for Br and 0.14 μg g−1 for I, allowing trace level determination in human hair. [ABSTRACT FROM AUTHOR]

Despite the recognized importance, the determination of halogens in Antarctic seaweeds remains understudied. Limited research exists due to challenges associated with sample preparation, and reliable analytical techniques for this type of analysis. Therefore, further investigations are necessary to bridge this knowledge gap and gain a comprehensive understanding of halogen metabolism in Antarctic seaweeds. In this study, seaweeds from the coast of the Antarctic continent were characterized concerning the total content of halogens and their species. For this purpose, different sample preparation methods, based on extraction and combustion, combining highly selective and sensitive chromatographic and spectrometric multi-technique approaches were used. By using optimized methods, it was possible to determine total halogens content, the distribution of bromine and iodine in different classes of species (lipids, water-soluble, proteins, carbohydrates, and residue), as well as the identification of iodinated amino acids (MIT and DIT) in ten brown and red seaweeds. Bromate and iodate were not detected in the samples, which presented only bromide and iodide species in their composition. Additionally, unknown bromine and iodine species were observed in different extracts evaluated. Furthermore, 25 halogenated polyphenols were identified in seaweeds, of which only four were already reported in the literature. The results obtained in this study comprise unprecedented data in the literature on species of halogens present in seaweeds from the Antarctic environment. [Display omitted] • First data in the literature on halogenated species in seaweed from the Antarctic. • A multi-technique approach was used to determine classes of halogenated compounds. • Sample preparation methods used were efficient to extract halogenated compounds. • Total halogen and its species were determined in ten Antarctic seaweed species. • Halogen distributions in lipid, water-soluble, protein, and carbohydrate fractions were showed. [ABSTRACT FROM AUTHOR]

In this study, the microwave-induced combustion (MIC) method was evaluated for the sample preparation of the most consumed mushroom species in Brazil (Champignon, Shiitake, and Shimeji) and further halogen determination by ion chromatography (IC). For this, sample mass, combustion aid mass, and absorbing solution (H2O and 50 mmol·L−1, 100 mmol·L−1, or 150 mmol·L−1 NH4OH) were evaluated. Bromine and iodine concentrations, determined by IC, were lower than the limits of detection (LODs, Br: 6 mg·kg−1 and I: 24 mg·kg−1). Inductively coupled plasma mass spectrometry (ICP-MS) was also used for Br and I determination, and the LODs were lower (Br: 0.066 mg·kg−1 and I: 0.014 mg·kg−1) than those obtained by IC. Concentrations of Cl, obtained by IC, ranged from 523 mg·kg−1 to 13053 mg·kg−1 with LOD of 40 mg·kg−1. In turn, Br and I concentrations, obtained by ICP-MS, ranged from 2.49 mg·kg−1 to 5.50 mg·kg−1 and from <0.014 mg·kg−1 to 0.047 mg·kg−1, respectively. Fluorine concentrations, determined by IC, were always lower than LOD (23 mg·kg−1). The trueness of the proposed methods was evaluated by recovery tests using standard solutions and a reference material (RM NIST 8435). When using the standard solution, recoveries ranged from 95% to 103% for halogen determination by IC and from 105% to 109% for Br and I determination by ICP-MS. When using the RM, recoveries of 102% for Cl by IC and of 87% and 86% for Br and I by ICP-MS, respectively, were obtained. [ABSTRACT FROM AUTHOR]

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 NH4OH 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. [ABSTRACT FROM AUTHOR]