Pharmaceutical Regulatory Affairs: Open Access

An aromatic polysulfone consists of 4,4’-diol aromatic compound and 4,4’-dichlorodiphenyl sulfone. As 4,4’-diol aromatic compounds, there exists bisphenol A, p-dihydroxy benzene, 4,4’-diphenol methane and p,p’-diphenol (bisphenol) and they were compared to study which compound would indicate the most resistant to gamma-ray exposure. Sulfur dioxide (SO2) from 4,4’-dichlorodiphenyl sulfone was used as an indicator for evaluation. The use of bisphenol in the preparation of polysulfone indicated the most resistant to the gamma-ray irradiation exposure and least production of SO2 among aromatic diol compounds tested. This indicated polysulfone free from bisphenol A is producible. The production of SO2 from bisphenol-based polysulfone was around 43% of bisphenol A based polysulfone. The rate of decrease of tensile strength correlated well with the order of radiation resistance. The fracture toughness of bisphenol A based polysulfone decreased with irradiation dose, but the bisphenol based polysulfone maintained its original ductility.

Many papers have been published so far on gas plasma sterilization. They are mostly conducted by physical researchers, so microbiology and chemical aspects are significantly insufficient. By joining the biologists and chemists, gas plasma sterilization research was outstandingly advanced. The mechanism was not clear until now and from the life time and some other reasons metastables can be the most appropriate factors for sterilization. Spore death is explained from the hydration of dipicolinic acid in the core. By attacking metastables spore surface was pin hole opened and the interior water and surrounding water penetrate into the core to hydrate DPA. DPA in the surface was collected with water and enriched with SPE (solid phase extraction) column. SPE drain was analyzed with C-18 column and eluted with an acetonitrile/water (1/4, v/v) and detected with 235 nm. Spore surface particle can be confirmed DPA. The hydration process can cause within spore, so spore figures are unchanged before and after sterilization.