ICP-MS Systems

Hewlett-Packard 4500 ICP-MS System
(Click here for information on designing an ICP-MS Experiment)

Our HP (now Agilent) 4500 ICP-MS is a transmisison quadrupole mass spectrometer. A "second generation" ICP-MS (instruments available today have reached what can be called the fourth generation) virtually all parameters are software controlled.

A Cetac ASX-500 Autosampler can handle 7, 15 and 50 mL tubes. Integrated peristaltic pumps handle variable speed uptake and waste removal. Our standard configuration is a Babbington nebulizer with a Scott-type spray chamber. The 4500 maintains the temperature of the spray chamber at 5 degrees C. The plasma can be operated from 900 to 1400 W, and typical is operated at 1250W. The Shieldtorch option can be employed to reduce interference from polyatomics and narrows the kinetic energy distribution of the ions. Typical flow conditions are 15 L/min plasma gas, 1 L/min auxiliary gas (also Ar) and 1.3 L/min nebulization gas.

We use Nickel sampling and skimmer cones. Once inside the vacuum region, the ion beam is exctracted from the jet, focussed, offset by about 1 cm to remove emitted light and residual neutrals, and then focussed into a unit mass resolution quadrupole. Detection by the electron multiplier is by pulse counting at low beam intensities and by current integration at high beam intensities (> 1.5 MHz).

Many metals can be analyzed in the low part-per-billion (ng/mL) region and slightly below and most metals can be analyzed to tens of parts-per-million (ug/mL). Consult with EAC staff about your particular metals and sample matrices before designing an experiment.

Training
EAC Staff will help you design your first experiment and teach you how startup, tune, validate and shutdown the instrument the first time you run samples. Be sure to allow plenty of lead time for planning your experiment and scheduling your training session. After training, you are expected to be self-sufficient for routine operation.

 

 

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