Reflections on 35 years of biological SRM production and analyses

Abstract

During the author's 39 years with the National Bureau of Standards (NBS)/National Institute for Standards and Technology (NIST) as an employee, and since then as Guest Researcher, he has been intimately involved with biological Standard Reference Material (SRM) production and analyses. His involvement with biological reference materials started with the very first biological certified reference material (CRM), the SRM 1571, Orchard Leaves, initiated in 1968 and issued in 1971, through the latest material (SRM 1575a, Pine Needles - renewal), issued in 2003. In addition, for more than 20 years he was Technical Coordinator for botanical SRMs for the NBS/NIST Analytical Chemistry Division. This paper contains his historical reflections and highlights from those years, and includes the techniques used to obtain and process these materials, new developments and procedures that resulted in vastly improved reference materials, the application of high accuracy neutron activation analysis to the certification of these standards, and the trace element quality assurance vital to the accuracy of these standards.