Inspection of urea capsules

Uniformity Take any 20 capsules, put them in appropriate vials, add a certain amount of water, dissolve them with slight heat, put a certain amount of solution in liquid scintillation bottles, measure the radioactivity counting rate of each bottle of solution, and calculate the average value of radioactivity counting. Compared with the average value, the radioactivity counting rate of at least 19 capsules should be 80.0 ~ 120.0% of the average value. Take this product as disintegration time limit. According to the inspection (China Pharmacopoeia 1995 Edition II Appendix XA), the disintegration time limit shall not exceed 8 minutes. Take radiochemical purity 1 capsule, dissolve it with appropriate amount of water, apply appropriate amount to one end of cellulose thin-layer plate (10× 140mm), and mix it with ethanol: ammonia water: water (8: 0). According to laws (People's Republic of China (PRC) Pharmacopoeia 1995 Edition II * * * and State Medical and Drug Administration, China Institute for the Control of Pharmaceutical and Biological Products, Drug Evaluation Committee of State Medical and Drug Administration, Shanghai Xinke Pharmaceutical Co., Ltd. and Beijing Senke Pharmaceutical Co., Ltd.), this standard has been implemented since March 29th, 2000, with a trial period of 2 years. During the protection period, other units may not copy. Appendix X Ⅲ i), when measuring the radioactive distribution with liquid scintillation counter, the radiochemical purity of urea [14C] should not be lower than 90%. Take a proper amount of solution for uniformity inspection and measure radioactivity. Based on the standard [14C] solution, the calculated radioactivity of the capsule should be 80.0 ~ 120% of the labeled amount.