ICP
MAKING STANDARDS
NUMBER OF STANDARDS
Determine the number of standards necessary
for your measurements (Blank, 100ppb, 500ppb,
1000ppb, etc)
BLANK
Blanks are prepared from
reagent grade water with 3%
trace metal grade nitric acid.
Blanks are typically prepared in
2L lots by adding 60 mL of
concentrated HNO3 to 1940 mL of
water (using a pre-marked bottle
available in the PQ lab).
IV-ICPMS-71A Standard
•
Typically, the ICP standard
used IV-ICPMS-71A, which
contains of 10 ppm Ag, Al,
As, B, Ba, Be, Ca, Cd, Ce,
Co, Cr3, Cs, Cu, Dy, Er, Eu,
Fe, Ga, Gd, Ho, K, La, Lu,
Mg, Mn, Na, Nd, Ni, P, Pb,
Pr, Rb, S, Se, Sm, Sr, Th, Tl,
Tm, U, V, Yb, Zn.
•
This solution is diluted with
the blank solution to prepare
working ICP standards.
100 ppb
Dilute the stock 100 times.
For a 200 ml sample pipette 2 ml of the ICP
Stock and dilute to 200 g with the blank solution.
500 ppb
Dilute the stock 500 times.
For a 200 ml sample pipette 10 ml of the ICP
Stock and dilute to 200 g with the blank solution.
1000 ppb
Dilute the stock 1000 times.
For a 200 ml sample pipette 20 ml of the ICP
Stock and dilute to 200 g with the blank solution.
Hints on Preparing Solutions
•
All bottles must be very clean.
•
Use gravimetric measurements whenever
possible.
•
Ie. Weigh solutions instead of pipetting.
•
Do not pipette directly out of ICP stock solutions;
pour instead into a falcon tube. This avoids
contamination.
•
Check the calibrates on pipettes when making up
standards.