Reference materials for beginners
Wednesday, September 4, 2019

An insight into the considerations behind the use of a reference material.

The thought behind the use of a reference material is simple. It is used as a benchmark in chemical analysis. Most analyses are rather comparative than absolute measurements. The analytical instruments show a relative signal which must be correlated to a known concentration of the analyte. This procedure is comparable to the gauging of a kitchen scale. In order to enable the scale to show you accurate readings it needs reference weights.

Reference material - A material, that relating to one or more predetermined properties is sufficiently homogenous, stable an determined to be fit for purpose within the confines of a measurment procedure.
ISO Guide 30:2015, 2.1.1

All analytical results, i.e. the content of heavy metals in soil must be verifiable and traceable. as demanded by national and international norms (DIN-, EN- and ISO). This requires so called matrix-matched reference materials. Soils for soils, ore for ore and ceramics for ceramics. There are three main apsects to a reference material: Homogeneity, purity and stability. Often it is difficult enough to fulfill one of these aspects, even more so when developing a method to produce materials suitable for micro-analysis.