Effects of pH and Buffer Concentration on the Thermal Stability of Etanercept Using DSC and DLS
スポンサーリンク
概要
- 論文の詳細を見る
The protein size, electrical interaction, and conformational stability of etanercept (marketed as Enbrel®) were examined by thermodynamic and light scattering methods with changing pH and buffer concentration. As pH of etanercept increased from pH 6.6 to 8.6, electrical repulsion in the solution increased, inducing a decrease in protein size. However, the size changed less in high buffer concentration and irreversible aggregation issues were not observed; in contrast, aggregates of about 1000 nm were observed in low buffer concentration at the pH range. Three significant unfolding transitions (Tm) were observed by differential scanning calorimetry (DSC). Unlikely to Tm1, Tm2 and Tm3 were increased as the pH increased. Higher Tm at high buffer concentration was observed, indicating increased conformational stability. The apparent activation energy of unfolding was further investigated since continuous increase of Tm2 and Tm3 was not sufficient to determine optimal conditions. A higher energy barrier was calculated at Tm2 than at Tm3. In addition, the energy barriers were the highest at pH from 7.4 to 7.8 where higher Tm1 was also observed. Therefore, the conformational stability of protein solution significantly changed with pH dependent steric repulsion of neighboring protein molecules. An optimized pH range was obtained that satisfied the stability of all three domains. Electrostatic circumstances and structural interactions resulted in irreversible aggregation at low buffer concentrations and were suppressed by increasing the concentration. Therefore, increased buffer concentration is recommended during protein formulation development, even in the earlier stages of investigation, to avoid protein instability issues.
- 公益社団法人 日本薬学会の論文
公益社団法人 日本薬学会 | 論文
- Effects of Nutrition Support Team Services on Outcomes in ICU Patients
- The Mechanisms of Insulin Secretion and Calcium Signaling in Pancreatic β-Cells Exposed to Fluoroquinolones
- Intrathecal Ketamine and Pregabalin at Sub-effective Doses Synergistically Reduces Neuropathic Pain without Motor Dysfunction in Mice
- Discovering Some Novel 7-Chloroquinolines Carrying a Biologically Active Benzenesulfonamide Moiety as a New Class of Anticancer Agents
- Novel Insights into Disease Modeling Using Induced Pluripotent Stem Cells