LEA蛋白特征片段及海藻糖对热敏性蛋白药物胰岛素冻干的协同保护

Synergistic Bioactive Protection of LEA-motif and Trehalose on Insulin during Freeze-drying

热敏性蛋白药物胰岛素的热稳定性较差,极易受制备方式和保存条件等影响而失活。故本研究分别利用高效液相色谱(HPLC)测定冻干样品中胰岛素的效价和差示扫描量热仪(DSC)测定冻干样品的玻璃化转变温度等重要参数,来研究胚胎发育晚期富集蛋白特征片段(LEA-motif,LEAM)和海藻糖冻干保护剂对胰岛素冻干保护效果的影响。冻干实验表明,两种保护剂均对胰岛素的活性具有保护效果,且LEAM的活性保护效果优于海藻糖。在效价和热稳定性方面,LEAM保护的胰岛素冻干品均高于海藻糖保护的胰岛素冻干样品。更为重要的是,两种保护剂协同保护时,少量海藻糖对于LEAM的保护特性具有增效作用。在冻干过程中,可有效提升药物玻璃态的稳定性,防止热致变性失活。由此可见,这种LEAM和海藻糖保护剂复合保护方法有望也可以应用在热敏性蛋白药物冻干粉针制备过程以保护药物活性。

Due to the poor heat stability, insulin is easy to lose its bioactivity during storage. Bioactive protection of LEA-motif （LEAM） and trehalose towards insulin was investigated respectively and synergistically. High performance liquid chromatography method was used to study the proficiency of insulin and differential scanning calorimetry was used to study glass transition temperature. According to the re- suits, both LEAM and trehalose can protect the bioactivity of insulin. The protective effect of LEAM is better than that of trehalose. That is to say that the bioactivity proficiency and heat stability of insulin within LEAM are better than those of insulin within trehalose. It is in- teresting that adding a bit trehalose can enhance the bioactive protection effect of LEAM towards insulin. During lyophilization, synergistic bioactive protection of LEAM and trehalose can not only enhance the stability of insulin, but also protect insulin from thermal degenera- tion. So such synergistic bioprotectants can be used to maintain the bioactivity of heat sensitive protein during lyophilization.