In a recent blog we explored the importance of instrument optimization for ICP-OES and ICP-MS, but all instruments should be frequently checked to confirm they are operating as expected. Preventive maintenance and appropriate start up and shut down SOPs are key to the integrity of analysis.
An ICP-MS system will operate and deliver numerical data even if not set up correctly or operating at expected levels. As discussed in a previous blog, , internal standards can be used to compensate for a variety of factors that degrade analytical performance, however, proper instrument set-up is core to data integrity. As a result, tuning of ICP-MS instruments is considered by most users to be a daily, if not more frequent, activity, and a prerequisite for achieving accurate results. Best practices dictate, and many standard methods require, that a sample sequence begin with an optimization block, during which a tuning solution is used to set-up the instrument.
ICP-OES is the go-to-technique across a number of industries, and when configured correctly, today’s instruments yield detection limits of 1 to 10 ppb for the majority of elements. Although a powerful elemental analysis technique, it is in fact a simple comparator, incapable of making absolute measurements.
LGC ARMI now has new analytical capabilities including ICP-OES, ICP-MS and WDXRF in our Manchester, NH facility. Our ISO 17025 laboratory is also equipped with the new ColdBlock rapid digestion system as well as other conventional sample preparation equipment.
We have received several questions regarding the best approach to cleaning solid samples and standards that have been prepared as chips for analysis by a total dissolution technique, such as ICP-OES or ICP-MS. Let’s first discuss common approaches for sampling, and then appropriate methodologies for ensuring chips are clean and free from contamination.
Metal alloys are commonly analyzed using solid sampling techniques such as Arc/spark optical emission spectroscopy (A/S OES), X-ray Fluorescence Spectroscopy (both Energy Dispersive (ED-XRF) and Wavelength Dispersive (WD-XRF)), and X-ray Diffraction (XRD). These techniques provide fast analysis with little or no sample preparation required, and can be provided as portable units, and in the case of XRF, hand-held units, for maximum flexibility. These techniques also are considered non-destructive in that the metal alloy is left largely unchanged after analysis, and is available for further testing or archiving.
The use of an Internal Standard (IS) can significantly improve both the accuracy and precision of your ICP-OES analytical results. This post addresses: how internal standards work, how to select an appropriate IS element, and how this methodology can be easily incorporated into your lab’s analytical procedures.
Generating high quality, accurate laboratory results starts with high quality, accurate standards. If your calibration standards are not correct, the analyses will not be accurate. Here are three common mistakes, and what you can do to avoid them, when preparing aqueous calibration standards for use in AA, ICP, or ICP-MS techniques.