|Budget Amount *help
¥1,800,000 (Direct Cost : ¥1,800,000)
Fiscal Year 1992 : ¥300,000 (Direct Cost : ¥300,000)
Fiscal Year 1991 : ¥700,000 (Direct Cost : ¥700,000)
Fiscal Year 1990 : ¥800,000 (Direct Cost : ¥800,000)
Study on variation of pharmaceutical activity of gamma-irradiated preparation was carried out using acrinol and pepsin. The obtained results are following.
1. Absorbed dose in radiation sterilization of pharmaceutical preparation By using Fricke dosimeter, it has been found experimentally that the absorbed doses of the samples in vessels of different sizes, materials, volumes and so on are not equal in the same gamma-irradiation condition. The fractional corrections of the exposure to the absorbed dose was estimated to be 6-7% for organic vessels and 9-10% for glass vial.
2. Study on radio-decomposition of pharmaceutical component in some dosage and G-values The radio-decomposed rate of acrinol as a model of pharmaceutical component in some different dosage, which were dry powder, aqueous solution and mixed state in dry or wet fillers, have been investigated in dose range of -300 kGy. As results, in the case of dry powder, the decomposed rate correlated to dose with linear. The other cases, the exponential correlations existed. However, in either case, the residual rate of acrinol after gamma-irradiation can be calculated by substitution of 3 kinds G-values for direct and indirect actions of gamma-ray, which are actual values Gs=1.25, Gw=0.80 and Gc=0.145.
3. The variations of enzymatic activity of pepsin by gamma-irradiation Variation of enzymatic activity of raw pepsin and saccharated pepsin preparation by gamma-irradiation was examinated in the dose range from 0 to 300 kGy. As results, retention rates of enzymatic activity at the dose of 25kGy were estimated to be 83% for raw pepein, and 86% and 93% for saccharated pepsin preparations, and at the dose of 10kGy, the rates were more than 93% for all pepsins. However, it is necessary to consider the fact that radiolytic products of lactose affect the measurement of enzymatic activity.