DeterminationofNa,Mg, P, K, Ca, Cr,Mn, Fe, Cu, Zn, Se, andMoby ICP-MS
5.
One-stepmicrowavedigestionprogram
Place theMARSXpress vessels into theCEMMARS5microwaveoven.Whenprogramming themicrowave, input
“organic” as the “sample type”, and “ramp to temperature”as the “control type”. Seedigestionparameters
below:
a)
Operatingparameters for stage1 sampledigestion
1
Power
100% (1600W)
2
Ramp to temperature
20minutes
3
Hold time
20minutes
4
Temperature
180 ºC
b)
Operatingparameters for stage2 sampledigestion
1
Power
100% (1600W)
2
Ramp to temperature
20minutes
3
Hold time
20minutes
4
Temperature
200 ºC
5
Cool down
20minutes
Note: Stages 1and2 shouldbeprogrammed to run sequentiallywithout any interruptions.
E.
STANDARDAND SOLUTIONPREPARATION
All storage conditions areat room temperatureunlessotherwise indicated. Solutionvolumesmaybe scaledas
needed.
1.
Nitric acidmaintenance solution for autosampler rinseport (approximately2%):
Mix20mLof concentrated
nitric acid (C.3.f)with20mL TritonX-100 solution (E.2) and laboratorywater topreparea total volumeof 1000
mL.Useperiod: Changequarterly (provideactual dateon label indicatingwhen to change solution).
2.
TritonX-100 solution (approximately5%):
Addabout 700mL laboratorywater toa1 Lplasticbottle containing
aTeflon-coated stirringbar. Place thebottleonamagnetic stirrer andbegin stirringat amoderate speed.
Slowlyadd50mLTritonX-100 fromagraduated cylinder.When theTriton isdissolved, fill thebottle to
approximately1000mLwith laboratorywater. Transfer to1 Lplasticbottle fittedwithaTeflon-constructed
dispenserwithadjustablevolume from1-10mL. This solution is added to theautosampler rinse solution to
minimize residuebuildup in the spray chamber. It does not affect theanalysis. Expiration: 6months.
MTE-02
FORWORKINGGROUP/ERPUSEONLY
DONOTDISTRIBUTE
