A systematic approach for harmonisation of reference material (RM) production and analytical method development using Reference Matrix Materials (RMMs) combined with a database for reporting

Analytical chemistry has changed profoundly over the last four decades with a tremendous expansion of analytical detection power. However, an increasing gap seems to exist between access to high-quality matrix Reference Materials and Certified Reference Materials (CRMs) and the sheer number of new analytes that can be determined in many matrices. The development of new RMs is moreover often connected with the use and development of novel measurement methods, especially in emerging fields of measurement. A challenge arises when characterising such RMs through interlaboratory comparisons, as it creates an RM/method causality dilemma, namely the production of new RMs require reliable and accurate methods, which in turn need good-quality RMs for method harmonisation and analytical quality assurance purposes. To overcome this dilemma, RM-producers must take iterative steps to gradually improve their candidate materials particularly with respect to homogeneity, which in turn allows improving the performance of the analytical methods. As both materials and methods evolve, they will eventually reach a point where target parameters can be certified in an appropriate matrix material. Provision of shared samples of specific matrices to a community of researchers could be a promising approach for future development of certified reference materials. This Trends article describes the components needed to establish such a resource and its expected outcomes. The core elements necessary for such a resource include (1) a material processing facility, (2) a storage and distribution centre, and (3) an online database for reporting measurement results. We propose the term Reference Matrix Materials (RMMs) for this category of samples. When multiple laboratories analyse RMMs, clusters of results eventually emerge in the database, tentatively providing a network of laboratories capable of performing specific measurements. Those results would subsequently become particularly valuable assets for RM-producers and proficiency testing providers. Method developers and analytical laboratories would also benefit from access to common materials enabling them to harmonise, compare, and evaluate the capabilities of different analytical methods. By providing such an anticipatory and dynamic platform, RM-producers and method developers can break open the closed circle of the RM/method causality dilemma. Such an approach could be a driver for faster, more universal, and efficient progress in the development of new RMs and analytical measurement methods alike.