Because it is made from pools of human serum that have been modified to achieve the target concentrations, this material may not be commutable for all routine glucose measurement procedures. However, NIST is unaware of any commutability problems with the

A unit of SRM 909b consists of six bottles of lyophilized human serum (three bottles each of two different analyte concentration levels) and six bottles of deionized, autoclaved water. Before use, the serum in each bottle is to be reconstituted with 10.00