NIST- SRM 1955a Homocysteine and Folate in Frozen Human Serum

NIST- SRM 1955a  Homocysteine and Folate in Frozen Human Serum


This Standard Reference Material (SRM) is intended primarily for use in evaluating the accuracy of clinical procedures for the determination of homocysteine and folate (in various forms) in human serum. It is also intended for use in validating working or secondary reference materials. A unit of SRM 1955 consists of three bottles of frozen human serum, each of a different analyte concentration level. Each bottle contains 1 mL of human serum.

The certified concentrations and their expanded uncertainties for total homocysteine (tHCY) and 5-methyltetrahydrofolic acid (5MT) are listed in Table 1. The certified concentrations of tHCY were determined at NIST using a combination of higher-order reference measurement procedures based upon isotope dilution with gas chromatography/mass spectrometry (GC/MS), liquid chromatography/mass spectrometry (LC/MS), and liquid chromatography/tandem mass spectrometry (LC/MS/MS) [1–3]. The certified concentrations for 5MT were determined by a combination of reference measurement procedures based upon isotope dilution LC/MS/MS performed at NIST [3,4] and the Centers for Disease Control and Prevention (CDC) [5]. The methods performed at NIST for tHCY and 5MT are recognized as approved higher order reference measurement procedures by the Joint Committee on Traceability in Laboratory Medicine (JCTLM) [6]. The certified concentrations apply only to serum thawed to room temperature, 20 °C to 25 °C (see “Instructions for Storage, Stability, and Use”). NIST- SRM 1955a

NIST通过认证和提供1300多种成分或财产特征良好的标准参考材料®,或两者兼而有之,支持准确和兼容的测量。作为整体质量保证计划的一部分,这些材料用于以单位进行仪器校准,以验证特定测量的准确性,并支持新测量方法的开发。 Homocysteine and Folate in Frozen Human Serum

工业界、学术界和政府使用NIST SRM来促进商业和贸易以及促进研发。目前,NIST SRM可用于工业材料生产和分析、环境分析、健康测量以及科学和计量学的基本测量等领域。NIST SRM也是支持美国测量可追溯性的一种机制。