1 0 0 0 OA セファロチンナトリウムの凍結相における結晶成長(第1報)凍結相における結晶化度の測定
- 著者
- 井上 正義 島 和弘 稲津 邦平
- 出版者
- 公益社団法人 日本薬学会
- 雑誌
- YAKUGAKU ZASSHI (ISSN:00316903)
- 巻号頁・発行日
- vol.104, no.9, pp.973-980, 1984-09-25 (Released:2008-05-30)
- 参考文献数
- 14
Investigation has been made to obtain the crystallinity of cephalothin sodium in seeded and frozen aqueous solution from electrical conductivity (conductivity), with a result that crystallinity (αt) can be given by the equation of αt=λT-λt/λT, where λT is the initial conductivity and λt stands for the conductivity obtained after t hours. Observed values of crystallinity by the conductivity method are in good agreement with crystallinity data by infrared method and X-ray diffraction method of the freeze-dried material. Further investigation has been made to find out whether it is possible to apply the no-seeding conductivity method for the crystallinity of dicethiamin hydrochloride in solution capable of spontaneous nucleation and transformation to its crystalline state. The result has consequently demonstrated that, in some cases of no-seeding, the phase transition is not uniform, or otherwise, the conductivity change provides an incomplete indication of nucleation and growth of perfect crystals. From the above, it may as well be said to be safe to set a limit to a seeded system, when the authors' conductivity method is applied for obtaining the crystallinity of a drug in frozen solution.
- 著者
- 井上 正義 田中 廣義 島 和弘 稲津 邦平
- 出版者
- 公益社団法人 日本薬学会
- 雑誌
- YAKUGAKU ZASSHI (ISSN:00316903)
- 巻号頁・発行日
- vol.105, no.3, pp.289-295, 1985-03-25 (Released:2008-05-30)
- 参考文献数
- 16
- 被引用文献数
- 1 1
The effect of organic solvent on the growth rate of cephalothin sodium (KF) after seeding in frozen solution was investigated. All of used solvents accelerated crystal growth of KF and it was found that the accelerative effect of solvent increased with an increase in dielectric constant of solvent. KF formed micelle in aqueous solution and the solvent lower the freezing temperature of the micelle and it can be assumed that the lowering of the freezing temperature of the micelle related to the volume of solvent existing in the micelle. Alcohol lower larger the freezing temperature of the micelle than ketone and nitrile, but the accelerative effect of alcohol on the growth rate was less than that of ketone and nitrile. The effect of the concentration of ethanol and acetone was investigated and it seemed that ethanol accelerated nucleation. Nevertheless, the accelerative effect of ethanol on the growth rate was less than that of acetone. These results suggested that simultaneous use of solvent having a different mode of action is effective for crystallization of KF in frozen solution by spontaneous nucleation.
1 0 0 0 OA セファロチンナトリウムの凍結相における結晶成長(第2報)種晶量, 濃度及び温度の影響
- 著者
- 井上 正義 島 和弘 稲津 邦平
- 出版者
- 公益社団法人 日本薬学会
- 雑誌
- YAKUGAKU ZASSHI (ISSN:00316903)
- 巻号頁・発行日
- vol.104, no.12, pp.1268-1274, 1984-12-25 (Released:2008-05-30)
- 参考文献数
- 10
- 被引用文献数
- 3 2
The growth rate of cephalothin sodium (KF) after seeding in frozen solution was measured. Crystal growth of KF followed equation (1) untill α=0.98. 1-(1-α)1/3=(1/3N) (Kt)N……(1) where α is crystallinity, K is rate constant, t is time, and N is parameter depending on the freezing temperature and the amount of seed. Crystal growth of KF in the frozen solution hardly changed when the concentration of KF was in the range of 19.4% to 28.6% but it was remarkably dependent on the amount of seed at the constant freezing temperature. According to the decrease in the amount of seed at the constant freezing temperature, the value of N increased and the rate constant (K) decreased. The growth rate increased with a rise of freezing temperature, and had the maximum value at a temperature little below the eutectic temperature. The activation energy of crystal growth of KF in the range of -5°C to -14°C was 49 kcal/mol.