ICP-MS

　　ICP-MS

　　The technique is best used for elements with masses greater than 80, mainly in the determination of rare earth elements (REE) and U, Th and Pb in geological materials. The instrument can analyse up to 30 samples per day. Normally we run batches of similar elements, e.g. Batch 1 REE; Batch 2 Transitions; Batch 3 Rb, Sr, Ba, Cs; Batch 4 U, Th, Pb. Therefore a typical 4 batch run for 30 samples requires 4 days of instrument time. The general internal standard used is 10 ppb indium, for U, Th, and Pb 10 ppb bismuth is used and for the REE 10 ppb of rhenium and ruthenium. Detection limits in ppb are listed in the table below. It is recommended, however, to work with concentrations at least 100 times the quoted detection limits for each element.

　　Element Detection Limit

　　ppb in solution

　　Li 0.13

　　Be 0.02

　　B 22.02

　　Sc 0.73

　　V 0.02

　　Cr 0.51

　　Co 0.02

　　Ni 0.31

　　Cu 0.27

　　Zn 0.26

　　Ga 0.01

　　Ge 0.08

　　As 0.005

　　Se 0.53

　　Br 0.67

　　Rb 0.01

　　Sr 0.02

　　Y 0.006

　　Zr 0.01

　　Nb 0.03

　　Mo 0.33

　　Ru 0.03

　　Rh 0.01

　　Pd

　　Ag 0.0006

　　Cd 0.04

　　In

　　Sn 0.09

　　Sb 1.30

　　Te 0.09

　　I 0.69

　　Cs 0.002

　　Ba 0.06

　　La 0.06

　　Ce 0.02

　　Pr 0.01

　　Nd 0.01

　　Sm 0.02

　　Eu 0.01

　　Gd 0.02

　　Tb 0.004

　　Dy 0.02

　　Ho 0.005

　　Er 0.01

　　Tm 0.005

　　Yb 0.03

　　Lu 0.01

　　Hf 0.004

　　Ta 0.004

　　W 0.95

　　Re

　　Os

　　Ir

　　Pt

　　Au 0.0002

　　Hg 1.28

　　Tl 0.04

　　Pb 1.23

　　Bi 0.004

　　Th 0.01

　　U 0.01