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Jens Jorgen Sloth - One of the best experts on this subject based on the ideXlab platform.
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spe hg aas method for the determination of inorganic arsenic in Rice results from method validation studies and a survey on Rice Products
Analytical and Bioanalytical Chemistry, 2013Co-Authors: Rie Romme Rasmussen, Yiting Qian, Jens Jorgen SlothAbstract:The present paper describes the development, validation and application of a method for inorganic arsenic (iAs) determination in Rice samples. The separation of iAs from organoarsenic compounds was done by off-line solid-phase extraction (SPE) followed by hydride generation atomic absorption spectrometry (HG-AAS) detection. This approach was earlier developed for seafood samples (Rasmussen et al., Anal Bioanal Chem 403:2825–2834, 2012) and has in the present work been tailored for Rice Products and further optimised for a higher sample throughput and a lower detection limit. Water bath heating (90 °C, 60 min) of samples with dilute HNO3 and H2O2 solubilised and oxidised all iAs to arsenate (AsV). Loading of buffered sample extracts (pH 6 ± 1) followed by selective elution of arsenate from a strong anion exchange SPE cartridge enabled the selective iAs quantification by HG-AAS, measuring total arsenic (As) in the SPE eluate. The in-house validation gave mean recoveries of 101–106 % for spiked Rice samples and in two reference samples. The limit of detection was 0.02 mg kg−1, and repeatability and intra-laboratory reproducibility were less than 6 and 9 %, respectively. The SPE HG-AAS method produced similar results compared to parallel high-performance liquid chromatography coupled to inductively coupled plasma mass spectrometry (ICP-MS) analysis. The SPE separation step was tested collaboratively, where the laboratories (N = 10) used either HG-AAS or ICP-MS for iAs determination in a wholemeal Rice powder. The trial gave satisfactory results (HorRat value of 1.6) and did not reveal significant difference (t test, p > 0.05) between HG-AAS and ICP-MS quantification. The iAs concentration in 36 Rice samples purchased on the Danish retail market varied (0.03–0.60 mg kg−1), with the highest concentration found in a red Rice sample.
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SPE HG-AAS method for the determination of inorganic arsenic in Rice—results from method validation studies and a survey on Rice Products
Analytical and Bioanalytical Chemistry, 2013Co-Authors: Rie Romme Rasmussen, Yiting Qian, Jens Jorgen SlothAbstract:The present paper describes the development, validation and application of a method for inorganic arsenic (iAs) determination in Rice samples. The separation of iAs from organoarsenic compounds was done by off-line solid-phase extraction (SPE) followed by hydride generation atomic absorption spectrometry (HG-AAS) detection. This approach was earlier developed for seafood samples (Rasmussen et al., Anal Bioanal Chem 403:2825–2834, 2012) and has in the present work been tailored for Rice Products and further optimised for a higher sample throughput and a lower detection limit. Water bath heating (90 °C, 60 min) of samples with dilute HNO3 and H2O2 solubilised and oxidised all iAs to arsenate (AsV). Loading of buffered sample extracts (pH 6 ± 1) followed by selective elution of arsenate from a strong anion exchange SPE cartridge enabled the selective iAs quantification by HG-AAS, measuring total arsenic (As) in the SPE eluate. The in-house validation gave mean recoveries of 101–106 % for spiked Rice samples and in two reference samples. The limit of detection was 0.02 mg kg−1, and repeatability and intra-laboratory reproducibility were less than 6 and 9 %, respectively. The SPE HG-AAS method produced similar results compared to parallel high-performance liquid chromatography coupled to inductively coupled plasma mass spectrometry (ICP-MS) analysis. The SPE separation step was tested collaboratively, where the laboratories (N = 10) used either HG-AAS or ICP-MS for iAs determination in a wholemeal Rice powder. The trial gave satisfactory results (HorRat value of 1.6) and did not reveal significant difference (t test, p > 0.05) between HG-AAS and ICP-MS quantification. The iAs concentration in 36 Rice samples purchased on the Danish retail market varied (0.03–0.60 mg kg−1), with the highest concentration found in a red Rice sample.
Rie Romme Rasmussen - One of the best experts on this subject based on the ideXlab platform.
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spe hg aas method for the determination of inorganic arsenic in Rice results from method validation studies and a survey on Rice Products
Analytical and Bioanalytical Chemistry, 2013Co-Authors: Rie Romme Rasmussen, Yiting Qian, Jens Jorgen SlothAbstract:The present paper describes the development, validation and application of a method for inorganic arsenic (iAs) determination in Rice samples. The separation of iAs from organoarsenic compounds was done by off-line solid-phase extraction (SPE) followed by hydride generation atomic absorption spectrometry (HG-AAS) detection. This approach was earlier developed for seafood samples (Rasmussen et al., Anal Bioanal Chem 403:2825–2834, 2012) and has in the present work been tailored for Rice Products and further optimised for a higher sample throughput and a lower detection limit. Water bath heating (90 °C, 60 min) of samples with dilute HNO3 and H2O2 solubilised and oxidised all iAs to arsenate (AsV). Loading of buffered sample extracts (pH 6 ± 1) followed by selective elution of arsenate from a strong anion exchange SPE cartridge enabled the selective iAs quantification by HG-AAS, measuring total arsenic (As) in the SPE eluate. The in-house validation gave mean recoveries of 101–106 % for spiked Rice samples and in two reference samples. The limit of detection was 0.02 mg kg−1, and repeatability and intra-laboratory reproducibility were less than 6 and 9 %, respectively. The SPE HG-AAS method produced similar results compared to parallel high-performance liquid chromatography coupled to inductively coupled plasma mass spectrometry (ICP-MS) analysis. The SPE separation step was tested collaboratively, where the laboratories (N = 10) used either HG-AAS or ICP-MS for iAs determination in a wholemeal Rice powder. The trial gave satisfactory results (HorRat value of 1.6) and did not reveal significant difference (t test, p > 0.05) between HG-AAS and ICP-MS quantification. The iAs concentration in 36 Rice samples purchased on the Danish retail market varied (0.03–0.60 mg kg−1), with the highest concentration found in a red Rice sample.
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SPE HG-AAS method for the determination of inorganic arsenic in Rice—results from method validation studies and a survey on Rice Products
Analytical and Bioanalytical Chemistry, 2013Co-Authors: Rie Romme Rasmussen, Yiting Qian, Jens Jorgen SlothAbstract:The present paper describes the development, validation and application of a method for inorganic arsenic (iAs) determination in Rice samples. The separation of iAs from organoarsenic compounds was done by off-line solid-phase extraction (SPE) followed by hydride generation atomic absorption spectrometry (HG-AAS) detection. This approach was earlier developed for seafood samples (Rasmussen et al., Anal Bioanal Chem 403:2825–2834, 2012) and has in the present work been tailored for Rice Products and further optimised for a higher sample throughput and a lower detection limit. Water bath heating (90 °C, 60 min) of samples with dilute HNO3 and H2O2 solubilised and oxidised all iAs to arsenate (AsV). Loading of buffered sample extracts (pH 6 ± 1) followed by selective elution of arsenate from a strong anion exchange SPE cartridge enabled the selective iAs quantification by HG-AAS, measuring total arsenic (As) in the SPE eluate. The in-house validation gave mean recoveries of 101–106 % for spiked Rice samples and in two reference samples. The limit of detection was 0.02 mg kg−1, and repeatability and intra-laboratory reproducibility were less than 6 and 9 %, respectively. The SPE HG-AAS method produced similar results compared to parallel high-performance liquid chromatography coupled to inductively coupled plasma mass spectrometry (ICP-MS) analysis. The SPE separation step was tested collaboratively, where the laboratories (N = 10) used either HG-AAS or ICP-MS for iAs determination in a wholemeal Rice powder. The trial gave satisfactory results (HorRat value of 1.6) and did not reveal significant difference (t test, p > 0.05) between HG-AAS and ICP-MS quantification. The iAs concentration in 36 Rice samples purchased on the Danish retail market varied (0.03–0.60 mg kg−1), with the highest concentration found in a red Rice sample.
Andrew A Meharg - One of the best experts on this subject based on the ideXlab platform.
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levels of infants urinary arsenic metabolites related to formula feeding and weaning with Rice Products exceeding the eu inorganic arsenic standard
PLOS ONE, 2017Co-Authors: Antonio J Signespastor, Jayne V Woodside, Paul Mcmullan, Karen Mullan, Manus Carey, Margaret R Karagas, Andrew A MehargAbstract:Early childhood inorganic arsenic (i-As) exposure is of particular concern since it may adversely impact on lifetime health outcomes. Infants’ urinary arsenic (As) metabolites were analysed in 79 infants by inductively coupled plasma—mass spectrometric detection (IC-ICP-MS) to evaluate i-As exposure pre- and post-weaning. Levels of i-As in Rice-based weaning and infants’ foods were also determined to relate to urinary As levels. Higher As levels, especially of monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA), were found in urine from formula fed infants compared to those breastfed. Urine from infants post-weaning consuming Rice-Products resulted in higher urinary MMA and DMA compared to the paired pre-weaning urine samples. The European Union (EU) has regulated i-As in Rice since 1st January 2016. Comparing infants’ Rice-based foods before and after this date, little change was found. Nearly ¾ of the Rice-based Products specifically marketed for infants and young children contained i-As over the 0.1 mg/kg EU limit. Efforts should be made to provide low i-As Rice and Rice-based Products consumed by infants and young children that do not exceed the maximum i-As level to protect this vulnerable subpopulation.
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survey of arsenic and its speciation in Rice Products such as breakfast cereals Rice crackers and japanese Rice condiments
Environment International, 2009Co-Authors: Paul N. Williams, Claire Deacon, Andrea Raab, Annemarie Carey, Jorg Feldmann, Andrew A MehargAbstract:Rice has been demonstrated to be one of the major contributors to arsenic (As) in human diets in addition to drinking water, but little is known about Rice Products as an additional source of As exposure. Rice Products were analyzed for total As and a subset of samples were measured for arsenic speciation using high performance liquid chromatography interfaced with inductively coupled plasma-mass spectrometry (HPLC–ICP-MS). A wide range of Rice Products had total and inorganic arsenic levels that typified those found in Rice grain including, crisped Rice, puffed Rice, Rice crackers, Rice noodles and a range of Japanese Rice condiments as well as Rice Products targeted at the macrobiotic, vegan, lactose intolerant and gluten intolerance food market. Most As in Rice Products are inorganic As (75.2–90.1%). This study provides a wider appreciation of how inorganic arsenic derived from Rice Products enters the human diet.
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Survey of arsenic and its speciation in Rice Products such as breakfast cereals, Rice crackers and Japanese Rice condiments
Environment International, 2009Co-Authors: Guo Xin Sun, Claire Deacon, Joerg Feldmann, A. M. Carey, Andrea Raab, Yong-guan Zhu, Paul N. Williams, Andrew A MehargAbstract:Rice has been demonstrated to be one of the major contributors to arsenic (As) in human diets in addition to drinking water, but little is known about Rice Products as an additional source of As exposure. Rice Products were analyzed for total As and a subset of samples were measured for arsenic speciation using high performance liquid chromatography interfaced with inductively coupled plasma-mass spectrometry (HPLC-ICP-MS). A wide range of Rice Products had total and inorganic arsenic levels that typified those found in Rice grain including, crisped Rice, puffed Rice, Rice crackers, Rice noodles and a range of Japanese Rice condiments as well as Rice Products targeted at the macrobiotic, vegan, lactose intolerant and gluten intolerance food market. Most As in Rice Products are inorganic As (75.2-90.1%). This study provides a wider appreciation of how inorganic arsenic derived from Rice Products enters the human diet. © 2008 Elsevier Ltd. All rights reserved.
Robert E Smith - One of the best experts on this subject based on the ideXlab platform.
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fast screening of lovastatin in red yeast Rice Products by flow injection tandem mass spectrometry
Journal of Pharmaceutical and Biomedical Analysis, 2012Co-Authors: Fenhong Song, Aref Eldemerdash, Robert E SmithAbstract:Abstract Drug adulteration in dietary supplement materials is a world-wide problem and poses a regulatory challenge. Red yeast Rice is a product used by consumers to lower blood levels of cholesterol. While most current methods to analyze red yeast Rice are based on HPLC separation with a photo-diode array detector and/or a mass spectrometry detector, which takes 20–40 min analysis time per sample, we developed a method to do fast screening of the active compound lovastatin by direct infusion into a mass spectrometer. This method takes under 1 min per analysis on the instrument. By using multiple reaction monitoring with five product ions, all the ion ratios of the analyte in the samples are compared with those from the standards for qualitative analysis. The results from this method were compared to the result from the liquid chromatography tandem mass spectrometry, which uses retention time and one ion ratio as the confirmation criteria. No false positives or false negatives were found among the 12 samples tested. The method also seems to be effective in measuring the lovastatin in red yeast Rice semi-quantitatively. This kind of method could be adapted to the screening of other dietary supplement Products.
Yiting Qian - One of the best experts on this subject based on the ideXlab platform.
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spe hg aas method for the determination of inorganic arsenic in Rice results from method validation studies and a survey on Rice Products
Analytical and Bioanalytical Chemistry, 2013Co-Authors: Rie Romme Rasmussen, Yiting Qian, Jens Jorgen SlothAbstract:The present paper describes the development, validation and application of a method for inorganic arsenic (iAs) determination in Rice samples. The separation of iAs from organoarsenic compounds was done by off-line solid-phase extraction (SPE) followed by hydride generation atomic absorption spectrometry (HG-AAS) detection. This approach was earlier developed for seafood samples (Rasmussen et al., Anal Bioanal Chem 403:2825–2834, 2012) and has in the present work been tailored for Rice Products and further optimised for a higher sample throughput and a lower detection limit. Water bath heating (90 °C, 60 min) of samples with dilute HNO3 and H2O2 solubilised and oxidised all iAs to arsenate (AsV). Loading of buffered sample extracts (pH 6 ± 1) followed by selective elution of arsenate from a strong anion exchange SPE cartridge enabled the selective iAs quantification by HG-AAS, measuring total arsenic (As) in the SPE eluate. The in-house validation gave mean recoveries of 101–106 % for spiked Rice samples and in two reference samples. The limit of detection was 0.02 mg kg−1, and repeatability and intra-laboratory reproducibility were less than 6 and 9 %, respectively. The SPE HG-AAS method produced similar results compared to parallel high-performance liquid chromatography coupled to inductively coupled plasma mass spectrometry (ICP-MS) analysis. The SPE separation step was tested collaboratively, where the laboratories (N = 10) used either HG-AAS or ICP-MS for iAs determination in a wholemeal Rice powder. The trial gave satisfactory results (HorRat value of 1.6) and did not reveal significant difference (t test, p > 0.05) between HG-AAS and ICP-MS quantification. The iAs concentration in 36 Rice samples purchased on the Danish retail market varied (0.03–0.60 mg kg−1), with the highest concentration found in a red Rice sample.
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SPE HG-AAS method for the determination of inorganic arsenic in Rice—results from method validation studies and a survey on Rice Products
Analytical and Bioanalytical Chemistry, 2013Co-Authors: Rie Romme Rasmussen, Yiting Qian, Jens Jorgen SlothAbstract:The present paper describes the development, validation and application of a method for inorganic arsenic (iAs) determination in Rice samples. The separation of iAs from organoarsenic compounds was done by off-line solid-phase extraction (SPE) followed by hydride generation atomic absorption spectrometry (HG-AAS) detection. This approach was earlier developed for seafood samples (Rasmussen et al., Anal Bioanal Chem 403:2825–2834, 2012) and has in the present work been tailored for Rice Products and further optimised for a higher sample throughput and a lower detection limit. Water bath heating (90 °C, 60 min) of samples with dilute HNO3 and H2O2 solubilised and oxidised all iAs to arsenate (AsV). Loading of buffered sample extracts (pH 6 ± 1) followed by selective elution of arsenate from a strong anion exchange SPE cartridge enabled the selective iAs quantification by HG-AAS, measuring total arsenic (As) in the SPE eluate. The in-house validation gave mean recoveries of 101–106 % for spiked Rice samples and in two reference samples. The limit of detection was 0.02 mg kg−1, and repeatability and intra-laboratory reproducibility were less than 6 and 9 %, respectively. The SPE HG-AAS method produced similar results compared to parallel high-performance liquid chromatography coupled to inductively coupled plasma mass spectrometry (ICP-MS) analysis. The SPE separation step was tested collaboratively, where the laboratories (N = 10) used either HG-AAS or ICP-MS for iAs determination in a wholemeal Rice powder. The trial gave satisfactory results (HorRat value of 1.6) and did not reveal significant difference (t test, p > 0.05) between HG-AAS and ICP-MS quantification. The iAs concentration in 36 Rice samples purchased on the Danish retail market varied (0.03–0.60 mg kg−1), with the highest concentration found in a red Rice sample.
