A permeation cup method for screening packaging materials for fragrance preservation in Chinese medicine

Abstract

Screening materials for permeability towards volatile components is important in order to select suitable packaging materials for medicines. This research for the first time has used a permeation cup method with gas chromatography-mass spectrometry (GC-MS) to screen the barrier properties of different packaging materials towards volatile components in oleum anisi stellati. A suitable GC-MS method was established to analyze standard oleum anisi stellati samples, and 30 components were identified. The standard samples were placed in permeation cups and covered with seven different types of plastic films. Then, they were placed in a (40 ± 2) °C/75% RH environment for 1, 2, 3, 7 and 14 days and the residual contents of each component were measured. The absorption of volatiles by the plastic films was also measured. The oxygen transmission rate (OTR) and water vapor transmission rate (WVTR) of each film were also measured separately as per ASTM D3985 and ASTM F1249. The results showed that the oleum anisi stellati samples covered with PET, nylon and EVOH (film) lost lower amounts of volatile components compared to the other plastic samples. PET showed the best barrier property towards volatile components in oleum anisi stellati. The OTR and WVTR measurements confirmed that PET, nylon, and EVOH samples had better barrier performance than the other types of plastic materials. There was a significant correlation observed between the loss of volatile components and their chemical structure and properties (such as surface tension, density and log S_w). All the films showed negligible absorption of the volatiles. Thus, this simple permeation cup method can be used to screen and select appropriate packaging materials for different types of drugs, fragrances and volatile samples.