In order to justify the suitability of the non-pharmacopoeial or equivalent primary reference standard, several structural elucidation methods should be used to confirm the molecular structure of the reference standard. In addition, validated analytical methods should be used to quantify the quantities of impurities such as organic impurities, inorganic impurities, water and residual solvents in the primary reference standard. The assigned content of the reference standard should then be calculated using the measured quantities of impurities and confirmed using other orthogonal quantitative methods (such as: QNMR, DSC, etc.) (Please refer to Ph. Eur. 9.0.5.12 reference standard.)

(中文版)