Objective: To develop a certified reference material (CRM) of β-sitosterol according to the Directives for CRM General and Statistical Principle for Certification (GB/T 15000.3-2008) based on the CRM project approved by Standardization Administration of the People's Republic of China (SAC). Method: β-Sitosterol was obtained from the dried seeds of Sinapisalba by means of silica gel column chromatography and recrystallization. The structure of β-sitosterol was confirmed by elemental analysis (EA)

UV

IR

MS

NMR and XRD. Thin layer chromatography was carried out for the identification

and after sample of β-sitosterol was divided into 300 bottles with 10 mg per bottle

the homogeneity test

stability test

and cooperative certification were carried out by high performance liquid chromatography with evaporative light-scattering detector (HPLC-ELSD). Result: The homogeneitywas good within 95% confidence interval. The stability was good within 24 months storage period at 0-8℃. The certified purity value was 95.41%with an expanded uncertainty of 0.30% (k=2). The CRM of β-sitosterol complied with the technical requirement of a series of GB/T 15000.3 guides about CRM

and it was checked and accepted by SAC. Conclusion: The national CRM of β-sitosterol was developed for the first time

which can be used in the content determination

method validation

testing and quality control of related products.