170135_inorganicventures_flipping

16.22 ICP-MS Measurement

Quan%ta%ve Analysis Measurement Techniques - Isotope Dilu,on

• The technique of isotope dilu,on ICP mass spectrometry (ID-ICP-MS) provides the analyst with the possibility of using a primary (defini,ve) analy,cal method for the determina,on of trace metals in a variety of sample types. • Examples of primary analy,cal methods are isotope dilu,on mass spectrometry (IDMS), ID- ICP-MS, gravimetry, ,trimetry, coulometry, differen,al scanning calorimetry and nuclear magne,c resonance spectroscopy. • ID-ICP-MS should be of par,cular interest to the Reference Material producer of materials for trace metals content. Unfortunately, there are several of the elements that are monoisotopic (9Be, 23Na, 27Al, 45Sc, 55Mn, 75As, 89Y, 103Rh, 127I, 133Cs, 141Pr, 159Tb, 165Ho, 169Tm, 197Au, and 232Th), making ID-ICP-MS useless for these elements. • Our laboratory has been studying ID-ICP-MS along with the execu,on of accurate isotopic abundance ra,o measurements (another possible primary method) and will publish these studies in the months to come

17.1 Method Validation

The process of solving a problem, whether involved or rela7vely straigh9orward, involves a logical process. The phases of this process are as follows :

• Phase 1: Problem Defini2on and Planning • Phase 2: Method Selec2on • Phase 3: Method Development • Phase 4: Method Valida2on • Method Established • Phase 5: Method Applica2on

• Phase 6: Data Evalua2on • Phase 7: Data Published • Problem Solved