ICP Procol

Getting samples

• Pre-measure tube weights (A)
• Harvest tissues and place in tubes
• Weigh tubes again (B)
• Tissue weight = (B) - (A)
• Transfer tubes in dry ice; keep frozen in -20 C

Making Samples ready

• Thaw tissue (-20 C) overnight in 4 C.
• Add 1ml of nitric acid
• Place parafilm over top; poke 1-2 holes
• Heat samples @ 90 C for 2 hrs
• Add 7 ml of MillQ water to each tube
• Use 0.2um syringe filter - filter back into tube
• Number all tubes clearly
• Cover tubes; store @ 4 C

Making ICP standards

Purchased Standard (Sigma # 74128) = 1000 ppm

Blank

(70%) x = (8.75%)(100 ml) x = 12.5

Add 100 ml Nitric acid to 700 ml MilliQ water = 800 ml total

1 ppm HIGH

(1000 ppm)(x) = (1 ppm)(250 ml)(x) = 250 ul

Add 250 uL of standard to 250 ml of blank

5 ppm HIGH

(1000 ppm)(x) = (5 ppm)(250 ml)(x) = 1.25 ml

Add 1.25 ml of standard to 249.75 ml blank

0.5 ppm QC

(1000 ppm)(x) = (0.5 ppm)(100 ml)(x) = 50 ul

Add 50 ul of standard to 100 ml blank

2.5 ppm QC

(1000 ppm)(x) = (2.5 ppm)(100 ml)(x) = 250 ul

Add 250 ul of standard to 100 ml blank

Clean all autoclaved bottles with diluted acid.