Description General description This certified reference material (CRM) is produced and certified in accordance with ISO/IEC 17025 and ISO 17034. This CRM is traceable to SI unit kg and measured against primary material from an NMI, e.g. NIST. Certified content incl. uncertainty and expiry date are given on the label. Download your certificate at: http://www.sigma-aldrich.com. Linkage Visit the IC Portal to learn more Analysis Note 1000 mg/L citrate in water, prepared with high-purity citric acid and water; filtered through a 0.2 μm membrane filter and stabilized with sodium azide Legal Information TraceCERT is a registered trademark of Sigma-Aldrich Co. LLC