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Materials Science in Additive Manufacturing Fibrous silk in biomedicine

a high risk of infection, poor biocompatibility, lack of proliferation with minimal cytotoxicity, ideal for wound
antibacterial properties, inadequate wound adherence, and dressing applications. Wang et al. developed dual-
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poor moisture management. Limited biocompatibility also functional FS expressing fibroblast growth factor-2 and
increases the risk of rejection reactions (e.g., skin redness, transforming growth factor-beta 1 for enhanced cell growth
itching), further escalating infection risks. Consequently, and anti-inflammatory responses. Wang et al. used a
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there is an urgent need for safer, more effective wound sericin-based system to engineer silkworms producing
dressing materials. The current research focuses on human acidic fibroblast growth factor-1, offering great
developing new dressing materials with antibacterial promise for skin wound healing through stimulated cell
properties, enhanced skin compatibility, and accelerated growth.
healing capabilities. 95,97
4.2. Cartilage tissue regeneration
FS offers superior mechanical strength, biocompatibility,
and cost-effectiveness. Its high structural and Human cartilage tissue consists of chondrocytes, matrix, and
morphological plasticity makes it an ideal biomaterials. fibers. It is categorized into hyaline cartilage, fibrous cartilage,
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Notably, FS effectively mimics the skin microenvironment, and elastic cartilage based on matrix composition. Lacking
aids in scar reduction, and treats atopic dermatitis. 98,99 nerves, blood, and lymphatics, cartilage exhibits limited self-
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Further, it promotes cell migration, proliferation, and repair capabilities due to its water-rich matrix. Damage
growth factor expression, enhancing wound healing to articular cartilage disrupts joint function, impacting
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through nuclear factor-κB signaling pathways. Thus, FS daily life and causing balance disorders in the human body.
represents a valuable material for skin repair, significantly Surgical intervention is often needed, with microfracture
enhancing anti-infection defenses and wound healing and autologous chondrocyte transplantation commonly
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outcomes. employed for minor injuries. At present, research focuses
on the development of biocompatible materials for cartilage
For skin tissue repair, FS can be processed using
physical, chemical, or genetic methods into hydrogels, repair. Critical requirements for these materials include
films, electrospun pads, and sponges suitable for wound biocompatibility to avoid immune rejection, controlled
dressings. For example, Li et al. fabricated FS films degradation, and mechanical properties that match the
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through hot pressing, enhanced with ε-polylysine, host tissue, with adjustability for various repair needs.
significantly accelerating wound healing, promoting In addition, materials must support cell attachment,
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granulation tissue formation, and increasing collagen proliferation, and integration with host tissue. A porous
deposition. Schneider et al. developed electrospun FS structure with interconnected pores is vital for nutrient
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pads loaded with epidermal growth factor, effectively transport and cell growth.
promoting wound healing, especially for chronic wounds. FS, a natural polymer, outperforms numerous natural
Fathi et al. co-electrospun polyvinyl alcohol, chitosan, and synthetic materials, especially for functional tissue
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and silk fibroin to produce hybrid fibers that exhibited replacements. Its superior mechanical properties,
superior mechanical and swelling properties and created a biocompatibility, controlled biodegradability, and
hydrophilic microenvironment conducive to cell adhesion adjustable porosity render it a prime candidate for cartilage
and proliferation in vitro, as well as wound healing and repair. However, the current research primarily utilizes
tissue regeneration in vivo. degummed silk treated with Na CO and dissolved in LiBr
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Moreover, FS dressings serve not only as basic to form a discontinuous SF solution. Researchers typically
antibacterial barriers but also as drug delivery systems. For blend the SF solution with other materials and utilize 3D
instance, Qin et al. fabricated a porous silk-based patch printing to fabricate cartilage bioscaffolds that foster cell
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through ice templating, enabling both wound protection growth, proliferation, and differentiation. 113-116 Conversely,
and controlled antibiotic (e.g., rifamycin) delivery. Sapru direct use of FS remains limited. This review focuses on FS
et al. developed a silk-serine nanofiber matrix with applications in cartilage repair to boost understanding and
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enhanced cell compatibility, blood compatibility, and further its potential in this field.
reduced immune reactivity, also boosting antibiotic Numerous studies confirm that SF solution combined
delivery to minimize infection and inflammation risks. with chopped FS can fill cartilage defects and boost
Genetic engineering further expands FS’s functionality chondrocyte regeneration. Singh et al. fabricated a
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by producing transgenic silk with embedded bioactive composite scaffold by combining chopped FS with SF
factors. For example, Wu et al. used the piggyBac system solution in a 2:1 (w/w) ratio. The resulting material
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to generate silkworms expressing truncated heavy chains exhibited superior swelling (25 – 30%) and degradation
of human epidermal growth factor protein, boosting cell rates (10 – 30%) due to its porosity. The addition of FS

Volume 4 Issue 2 (2025) 9 doi: 10.36922/MSAM025130020