Reference materials are one of the cornerstones in producing reliable chemical measurements and, as such, have a wide range of applications in the laboratory. These include:
- method validation
- instrument calibration
- verification of instrument, laboratory & analyst performance
- uncertainty estimation
- internal quality control
Of these, the most common uses are for the calibration of instruments, usually using standard solutions made up from known purity reference materials, and for the validation of test methods using matrix reference materials that, ideally, will closely resemble the samples being analysed.
Both types of reference material are essential to the analytical process. Whereas a standard solution is necessary for calibrating the response of a measuring instrument, a matrix reference material is equally necessary to assess suitability of a complete analytical process.
In general, reference materials should be used on a regular basis within the framework of a sound quality assurance system. When used in this manner, the analyst can feel confident that the analytical system is under statistical control and is producing results that are fit for purpose.