SRM Story: SRM 965c Glucose in Frozen Human Serum

The Centers for Disease Control and Prevention (CDC) estimates that over 40 % of Americans suffer from diabetes-related conditions, including 29 million diagnosed, 9 million undiagnosed, and 98 million with prediabetes. Diabetes is a chronic but manageable health condition in which the body cannot properly process sugar that is consumed through the diet. Generally, our bodies produce a hormone called insulin that helps transport the glucose we eat through our blood and into our cells, where that glucose is used as energy. A diabetic person’s body, however, doesn’t produce enough insulin or doesn’t use its insulin effectively, causing glucose to build up in the blood and potentially result in organ damage. Monitoring of blood glucose levels and making informed choices about diet, exercise, and medication help diabetics maintain their glucose levels in a healthy range and prevent complications. NIST supports accuracy of blood glucose monitoring by providing SRMs designed for calibrating and validating clinical glucose measurements.

SRM 965c Glucose in Frozen Human Serum is the fourth iteration of this reference material series, available to support accurate determination of glucose in human serum, since 1996. Released in March 2025, the SRM includes four different blood serum materials with varying levels of glucose, including one low level, two moderate (healthy) levels, and one high level. The glucose mass fractions in these materials were determined using the gold standard approach – one Reference Measurement Procedure approved by the Joint Committee for Traceability in Laboratory Medicine based on isotope dilution liquid chromatography tandem mass spectrometry (ID-LC-MS/MS) implemented at NIST and a second candidate Reference Measurement Procedure based on ID-GC-MS developed at the CDC. The availability of this SRM and its accompanying Certificate of Analysis (COA) is essential to ensure users, such as clinical laboratories who test patient samples and companies developing tests for blood glucose monitoring, can appropriately calibrate and validate their testing methods and ensure the accuracy of blood glucose monitoring for diabetes management.

As the US National Metrology Institute (NMI), NIST provides materials like SRM 965c to enable users to establish metrological traceability to the International System of Units (SI). The international network of NMIs, including NIST, maintain measurement equivalence through SI traceability that ensures for decades to come, in laboratories around the world, measurement of blood glucose will be accurate and comparable. Tools such as NIST SRMs have enabled development and deployment of modern technologies for continuous glucose monitoring that have simplified the management of diabetes and may lead to further reductions is diabetes-related complications and death in the future.