BS ISO 21424:2018,Milk, milk products, infant formula and adult nutritionals — Determination of minerals and trace elements — Inductively coupled plasma mass spectrometry (ICP-MS) method.
BS ISO 21424:2018 is applicable for the determination of all 12 elements in infant formula and adult nutritional products.
Principle
Nitric acid, internal standard, and hydrogen peroxide are added to the sample in microwave vessels and the samples are digested at 200C using a pre-programmed temperature control digestion. The addition of hydrogen peroxide helps reduce carbon and nitrous oxide levels in the digestate. The presence of carbon in the samples causes signal enhancement of Se. Therefore, to matrix match the samples, carbon in the form of methanol is added to both the standard solutions and the digestate before analysis. An ionization buffer is not necessary because the multielement standards and samples always contain significant amounts of the easily ionized elements.
Quality control sample (QCS)
Standard Reference Material (SRM) @ 1849a2) milk-based hybrid infant/adult nutritional powder with certified values for Ca, Cu, Cr, Fe, Mg, Mn, Mo, P, K, Se, Na, and Zn Supplied as a unit of 10 packets eachcontaining approximately 10 g of material. This is the recommended control material for this analysis,but other suitable SRMs could be substituted.
BS ISO 21424:2018 PDF is free to download on www.freestandardsdownload.com,and hope it can help you more.