Simplified Calibration for Total-Reflection X-ray Fluorescence

Araneda, Axel A.; Sanhueza, Vilma; Bennun, Leonardo

doi:10.1080/00032719.2015.1118486

Cited by 4 publications

(1 citation statement)

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“…Galium was added as internal standard in these solutions with a constant concentration of 5 μg/mL. The TXRF spectra of these standards were measured for 500 s and the relative sensitivities with respect to Ga were determined, as is described in our previous studies 29,30 .…”

Section: Fig 1: Structure Of the Cianocobalamine Moleculementioning

confidence: 99%

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2018

IJPSR

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This manuscript presents the application of a detailed set of analytical technologies to the content of assorted micronutrient supplement and mineral supplement products on the market in the city of Concepcion, Chile. We applied TXRF as a screening technique for the evaluation of 1) The vitamin B-12 content in multivitamins and 2) the elemental composition (P, K, Ca, Mn, Cr, Fe, Cu and Zn) in mineral supplements. The analyzed 16 products (10 sold as pills, 3 as syrups, and 3 as solutions for intramuscular injections), were acquired directly from drugstores without medical prescription. They were processed in 3 different laboratories in order to avoid systematic errors. In the samples we evaluated: 1) The presence of the specified elements, 2) The correlation between the labelled contents and our evaluations; and 3) The possible presence of harmful elements for human health. In this study few anomalies were found: 1) in some products there are significant differences between the concentrations labelled and our evaluations.2) The absence of cobalt in four of these vitamin B-12 containing products, 3) The presence of lead in a sample for intramuscular injection, 4) Arsenic was found in one of them, and 5) A trace detection of a rare earths element (possibly Ytterbium) in a particular product. The products studied are imported from different countries and they are labelled in their country of origin, so the questions about the safety and efficacy aspects of them could affect not only to Chilean consumers.

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Section: Fig 1: Structure Of the Cianocobalamine Moleculementioning

confidence: 99%