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.
In a previous blog post “How to prepare metal alloy samples for analysis by ICP-OES or ICP-MS”, my colleague Sue Evans Norris described the traditional methods for metal alloy sample preparation. At ARMI, we are always looking for ways to improve the status quo and recently discovered a new sample preparation technology for the rapid digestion of metal alloys using short-wave infrared radiation. This technology, promoted by a Canadian company called ColdBlock, claims their instrument can digest metal alloys faster than current techniques while eliminating the need for dangerous acids such as hydrofluoric and perchloric acid.
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.