Page 67 - MSAM-4-2

Materials Science in Additive Manufacturing Fibrous silk in biomedicine

Table3. Summary of advantages and disadvantages of fibrous silk in biomedical applications

Advantages Disadvantages
Excellent and tunable mechanical properties (high tensile Insufficient mechanical strength in certain contexts compared to synthetic materials such
strength and ductility) as polylactic acid or polyetheretherketone
Superior biocompatibility and low immunogenicity Unclear long-term in vivo safety; potential toxicity from degradation products requires
investigation
Good biodegradability with adjustable degradation rates Precise degradation control is challenging due to environmental and structural variability
Excellent antibacterial and antiviral properties Antibacterial properties may diminish when combined with other materials or under
long-term applications
Structural diversity and functional tunability Lack of standardization and certification pathways hinders regulatory approval,
particularly in AM-based products
Good compatibility with various biomaterials Processing complexity in additive manufacturing may result in issues such as incomplete
crystallization, insufficient crosslinking, and unsatisfactory material uniformity.
Broad potential in biomedical applications (e.g., tissue High production cost relative to synthetic alternatives, especially for purification and
engineering, drug delivery, wound healing) functionalization steps
Eco-friendliness and sustainability Raw material supply is limited by silkworm species and feeding conditions, impacting
yield consistency and stability

Table4. Comparison of fibrous silk, collagen, and synthetic polymers(polylactic acid[PLA]/polycaprolactone[PCL]) in

biomedical applications
Criteria Fibrous silk Collagen Synthetic polymers(PLA/PCL)

Mechanical properties High tensile strength, good ductility Low tensile strength, rapidly Broadly tunable, moderate strength
degradable
Degradation rate Slow (usually > 12 weeks), suitable for Fast (days to weeks), suitable Tunable (weeks to months), varies with
long-term support for short-term applications structure and copolymer ratio
Biocompatibility Excellent, with low inflammatory response Excellent, naturally derived, Good; may cause mild to moderate
minimal immune rejection inflammation
Immunogenicity Low post-degumming, though sericin Extremely low (especially in Potential risk depending on synthesis and
residues or degradation products may elicit human-derived forms) degradation byproducts
responses

Antibacterial properties Lacks intrinsic activity but can be enhanced None; typically requires Typically non-antibacterial; requires functional
(e.g., with ε-polylysine) antibiotics additives
Formability (e.g., 3D Compatible with hydrogels/composites; Poor; not suitable for Good thermal processability; suitable for 3D
Printing) under exploration complex structures printing, injection molding, etc.
Cost Medium to high; limited by extraction/ Low; mature extraction Low to medium; inexpensive raw materials and
purification/recombinant techniques technology mature scale-up production
Scalability Technical bottlenecks exist; recombinant High industrial maturity; Industrialized and mature; stable supply chain
fibrous silk production is still under established raw material
development supply
Structural modifiability and High; easy to modify (e.g., growth factors, Moderate; limited by High; molecular design flexibility, easy
functionality conductivity) structure stability functional integration

Clinical prospects Broad potential, especially in soft tissue and Extensively used (e.g., skin Already implemented in degradable scaffolds,
bone regeneration grafts, soft tissue, cardiac sutures, drug delivery systems, etc.
tissue engineering)

degradation byproducts may trigger chronic inflammation From a mechanical standpoint, natural FS has
or amyloid deposition, highlighting the need for further inherent limitations. While its tensile strength surpasses
investigation into their long-term biosafety. that of collagen and polylactic acid, it remains inferior

Volume 4 Issue 2 (2025) 16 doi: 10.36922/MSAM025130020