Relationship between molecular state and function in silk fibroin-based bioabsorbable scaffold

2023 Fiscal Year Final Research Report

• Project/Area Number: 22K20483
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0401:Materials engineering, chemical engineering, and related fields
• Research Institution: Kumamoto University
• Principal Investigator: Sasaki Makoto 熊本大学, 大学院先端科学研究部(工), 特任准教授 (80768812)
• Project Period (FY): 2022-08-31 – 2024-03-31
• Keywords: シルクフィブロイン / 精練 / 生体吸収性 / 医療機器応用

Outline of Final Research Achievements

Degumming with an aqueous alkaline solution is the initial step to purify silk fibroin (SF) aqueous solution from silkworm cocoon. While the process is essential to remove sericin, it affects the molecular state of SF. In this study, we focused on the physical and biological properties of the films prepared using different SF aqueous solutions, which were obtained through the degumming with Na2CO3 aqueous solutions at various concentrations, followed by water solubilization and dialysis.
It was confirmed that increase in the concentration of Na2CO3 resulted in a wider distribution of molecular weight of SF in the purified aqueous solution. The prepared SF film with the high content of low molecular weight chains below 100kDa performed faster degradation rate and lower fibroblast adhesion than that with high molecular weight chains. In a rat abdominal adhesion model, the former tended to inhibited postoperative adhesion, and the latter promoted the adhesion on the wound site.

Free Research Field

Biomaterial

Academic Significance and Societal Importance of the Research Achievements

SFは優れた生体適合性を有していることが報告されているにも関わらず、国内において生体吸収性医療機器（スキャフォールド）へ応用された事例は皆無である。本研究では、SFフィルムにおける分子状態（分子鎖長や分子量分布）と機能（機械特性や分解性、細胞接着性）との重要な関係性を確認することができた。これは、成形加工工程における些細な条件の違いが、成果物の機能に多大なる影響をもたらすことを示唆する。これらの深い理解は、スキャフォールド開発における一助となり得る。