This Standard Reference Material (SRM) is intended primarily for use in evaluating the accuracy of procedures for the determination of creatinine in human urine. It is also intended for use in validating working or secondary reference materials. SRM 3667 was prepared from normal human urine collected from male and female donors, and the creatinine concentration has not been modified. A unit of SRM 3667 consists of one bottle of 10 mL frozen human urine. For more information, please refer to the SDS and the COA.