一般論文
凍結乾燥によるタンパク質の安定化に関する研究―マンニトールによる安定化―
2004 年 64 巻 3 号 p. 180-185
詳細
2004 年 64 巻 3 号 p. 180-185
In order to solve the mechanism about the stabilization by freeze drying the protein used for medical treatments, basic Fibroblast Growth Factor (bFGF: M. W. 17000) was used as a model protein, as well as mannitol for a crystalline freeze-drying base. bFGF was freeze dried with mannitol at concentrations ranging from 0% to 100% (w/w). Differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and high performance liquid chromatography (HPLC) were used to evaluate bFGF/mannitol interaction by the samples after freeze drying and storage samples through stored at 30°C, 40°C and 50°C for 10 days. The result of DSC showed that according to the ratio of bFGF and mannitol, each formulation had different crystallinity and melting points respectively. Moreover, FTIR results showed that in each formulation after freeze drying, the random structure peak of bFGF shifted to a higher wave number as the mannitol ratio increased. Also, in the storage samples, it was found that the random structure peak of bFGF shifted to a higher wave number in heat dependence. Furthermore, HPLC results showed that it was the same degradation pathway of bFGF in each formulation. This work suggests that although the interaction of bFGF and mannitol influenced the crystallinity of formulation, stabilization of bFGF with mannitol is difficult. At the same time, it is thought that an amorphous structure has contributed to the stabilization of bFGF since secondary structure change of bFGF is in inverse proportion to an amorphous quantity in formulation.
