Objective: To propose updates and amendments for the nitroglycerin tablets quality in the Chinese pharmacopoeia 2020 due to the failure of effective separation of 4 known impurities and nonseparation of free nitrate ion and excipients.
Methods: Related substances were analyzed using gradient elution by HPLC, and free nitrate ion was determined on SAX column by different HPLC method.
Results: Using the improved method to test the related substances and free nitrate ion of nitroglycerin tablets,the content of the maximum individual impurity were not more than 0.5%, the total content was not more than 2.4% and the content of free nitrate ion was not more than 6.3%.
Conclusion: The improved method is accurate and feasible. It provided a reference for the updates and amendments of the quality standard of nitroglycerin tablets in the Chinese Pharmacopoeia 2020.