Optimizing the uses and the costs of reference materials in analytical laboratories

Many different analytes are determined on a daily basis in many different matrices, and the quality control (QC) for these determinations requires the use of reference materials (RMs), not only certified reference materials (CRMs) but also quality-control materials (QCMs) for routine purposes (e.g., control charting). In majority of cases, such materials are unavailable.Since QCMs cannot be an alternative to CRMs, but at best are a supplementary tool, the possibility of producing them on a small scale, in-house, may be considered. Until now, despite substantial subsidies given by various European Commission projects, it has been impossible to show that in-house production really is an economically feasible way of providing RMs to a market rather than only a good way of getting proper tools for QC when there is nothing else available.This article provides guidance and some considerations to be taken into account by laboratories that have decided to undertake preparation of in-house RMs for their own internal use to optimize the cost of materials and to get a good quality product.