在配制维生素C 注射液时,为防止氧化降解,除了添加抗氧剂、螯合剂外,还在溶液中和安瓿熔封时通入惰性气体,以驱逐氧气增强稳定性。一般都在溶液和安瓿空间通入CO_2。但是安瓿空间的CO_2如果通入过多,则封残率高(可达10%以上);通入量少,氧气驱逐不完全,稳定性差。我们在工作实践中发现,用N_2代替CO_2,可以解决封残率高 In the preparation of vitamin C injection, in order to prevent oxidative degradation, in addition to adding antioxidants, chelating agents, but also in the solution and the ampoule melted sealing inert gas, in order to drive the oxygen to enhance stability. CO 2 is usually introduced into the solution and ampoule space. However, if the amount of CO_2 in the ampoule space is too high, the residual rate is high (up to 10% or more); less inflow, incomplete oxygen evacuation and poor stability. In our work practice, we found that replacing N_2 with CO_2 can solve the problem of high residual rate