Biopharma Micropress冻干饼强度测试仪

疫苗的冷冻干燥-在配方和工艺开发中的挑战和概念

Vaccination prevents millions of deaths from infectious diseases per year; however, there are still millions of people who die from these diseases due to weak thermostability demanding cold chains, long-term stability issues and distribution challenges. All these limitations can be overcome by creating a dry product through lyophilization. With the urgency to develop a coronavirus vaccine, it is a crucial time to discuss the process of freeze-drying vaccines.

冻干机设备性能的测量：两种方法的比较

The objective of this investigation was to evaluate two methods for measuring the maximum sublimation rate that a freeze-dryer will support—the minimum controllable pressure method and the choke point method. Both methods gave equivalent results, but the minimum controllable pressure method is preferred, since it is easier, faster, and less subjective. The ratio of chamber pressure to condenser pressure corresponding to the onset of chokedflflow was considerably higher in this investigation (up to about 20:1) than in previously published reports. This ratio was not affected by the location of the pressure gauge on the condenser; that is, on the foreline of the vacuum pumpversuson the body of the condenser itself. The total water loss due to sublimation as measured by tunable diode laser absorption spectroscopy was consistently within 5% of gravimetrically determined weight loss, regardless of whether the measurement took place during chokedversusnon-choked process conditions.