Blister packaging is a common form of pharmaceutical packaging. The medicines in each blister are independent of each other. Taking out the medicine in one blister will not affect the sealing and barrier properties of the medicine in other blisters, so it will affect the quality of the medicine. better. The barrier properties of blister packaging mainly include the barrier properties to oxygen and water vapor, so as to prevent the oxidation of the active ingredients in the drug and the deliquescence of the drug.
The oxygen barrier properties are verified through the oxygen permeability test, using the isobaric test principle. The sample is clamped on the testing equipment through a special clamp, and then the blister package and the clamp are covered with a sealing structure. On both sides of the blister package, oxygen is introduced on one side, and oxygen is introduced on the other side. Pressurized high-purity nitrogen, under the action of concentration difference, the oxygen that penetrates into the nitrogen side through the blister package is carried by the flowing nitrogen to the sensor for analysis, thereby obtaining the oxygen penetration amount of the blister package. The reference standard is ASTM D3985.
The water vapor barrier properties are verified through the water vapor transmission rate test. The detection methods that can be used include the infrared method and the electrolysis method. The sample processing and clamping process is similar to the oxygen permeability test. The difference is that on both sides of the blister package, dry high-purity nitrogen flows on one side, and on the other side flows high-purity nitrogen with a certain humidity. , under the influence of humidity difference, water vapor will penetrate from the high-humidity side through the blister packaging to the low-humidity side, and will be carried by the nitrogen on the low-humidity side to the sensor for analysis, thereby obtaining the water vapor transmission amount of the blister packaging. The standard that can be referred to when using the infrared method for testing is ASTM F1249. There is no relevant standard for electrolytic methods to test the water vapor permeability of containers.
It is recommended to use Saicheng's WPT-204 water vapor transmission rate tester for water vapor barrier testing of blisters, and the ISOBARIC-404 oxygen transmission rate tester for oxygen barrier performance testing. Both instruments use four-chamber independent testing, with high testing efficiency and a wide range of temperature and humidity control.