Analyte Matrix/Material Name of the reference material Producer Quantity

The following reference materials are no longer listed in the JCTLM database that publishes available higher-order reference materials and reference measurement methods or procedures categorized in three lists: List I: Certified reference materials and reference measurement methods/procedures for well-defined chemical entities or internationally recognized reference method-defined measurands. Reference materials and measurement methods/procedures included in this category are those that provide values that are traceable to the SI units; e.g., electrolytes, enzymes, drugs, metabolites and substrates, non-peptide hormones, and some proteins. List II: Reference materials for which values of the measurands are not SI-traceable but are assigned by or traceable to an internationally agreed upon protocol, e.g., reference materials for blood typing, coagulation factors, microbial serology, nucleic acids, and some proteins. List II also contains a group of purified substances which, due to the absence of reference measurement procedures, should not be directly used for calibration of routine methods unless commutability is established and/or matrix effect independent internationally recognized standardized value transfer protocols to commutable samples are applied