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Materials Science in Additive Manufacturing Fibrous silk in biomedicine

physical approaches to produce composites and modified E. coli, S. aureus, and Pseudomonas aeruginosa. These
silk materials for medical applications. 174-176 These findings offer valuable insights into the development of
techniques aim to improve FS’s antimicrobial efficacy, next-generation antibacterial medical textiles and the
opening new avenues for medical material applications. continued advancement of medical supply innovation and
In the preparation of antimicrobial silk composites, hospital infection control practices.
a combination of synthetic and natural agents Moreover, FS modified through artificial feeding has
(e.g., quaternary ammonium compounds, inorganic shown enhanced antibacterial performance. Zhang et al.
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nanomaterials, chitosan, and bioactive substances) has encapsulated glucose around silver nanoparticles, applied
been incorporated with FS to enhance antimicrobial the solution to mulberry leaves, and fed them to silkworms.
performance. For example, Zhang et al. used ionic The resulting FS exhibited antibacterial rates ranging from
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interactions to coat FS with 0.5% tannic acid, resulting 72.5% to 95.9% against E. coli and from 50.8% to 95.9%
in durable antibacterial activity suitable for medical against S. aureus when cultured with bacteria. Notably,
applications. Similarly, Zhao et al. demonstrated that the antibacterial effect was positively correlated with the
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FS chemically modified with sodium alginate–AgNPs concentration of silver nanoparticles, especially against
exhibited robust antibacterial activity against E. coli and E. coli, indicating a dose-dependent response. The study
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S. aureus. Li et al. developed a de-gummed FS/nano- demonstrated that artificial feeding can alter the secondary
hydroxyapatite/polylactic acid scaffold infused with structure of FS, significantly improving its antibacterial
nanosilver, which exhibited both mineralization potential performance.
and notable antibacterial properties in vitro. Liu et al.
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utilized FS as a biotemplate for in situ integration of Fe O 5. Three-dimensional printing of FS -based
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and Ag nanoparticles, producing Ag–Fe O –SF composites biomaterials
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with strong antibacterial effects against E. coli and S. aureus, Three-dimensional printing, also known as AM, is defined
offering the potential for water disinfection applications. as “a process of creating objects by joining materials
In a separate study, Li et al. enhanced FS’s antibacterial layer by layer, based on 3D model data, as opposed to
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properties by chemically attaching nano TiO –Ag particles, traditional subtractive manufacturing methods.” In
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suggesting that both nano TiO –Ag and nano zinc particles recent years, 3D printing technology has rapidly advanced,
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could further improve FS’s antibacterial attributes. finding applications across diverse fields ranging from
Valarmathi and Sumathi employed electrospinning to automotive engineering to organ transplantation. 189-192
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fabricate FS-based fiber composites incorporating methyl Due to its excellent biocompatibility, biodegradability,
cellulose and zink–hydroxyapatite, with tests confirming and integration with host tissues, FS has been extensively
that zink–hydroxyapatite significantly improved the studied as a scaffold material in tissue engineering and
composite’s antibacterial activity. regenerative medicine. The advent of 3D bioprinting has
Medical supplies derived from antibacterial FS further revolutionized these fields by enabling the high-
composites offer valuable solutions for hospital sterilization, precision and repeatable fabrication of intricate biological
textile production, and environmental purification. These structures. FS-based bioinks exhibit tremendous potential
materials, endowed with inherent antibacterial properties, in 3D bioprinting due to their favorable printability,
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can also serve as effective skin wound dressings. Li et al. mechanical robustness, and cytocompatibility. Over
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introduced natural antibacterial FS membranes – also the past four decades, various 3D printing methods have
referred to as flat silkworm cocoons (FSCs) – tailored for been adapted for FS processing. 14,193 The three primary
wound care applications. They integrated ε-polylysine techniques currently used in bioprinting include: (i) inkjet
(EPL) onto FS membranes through hot pressing, thereby 3D printing, (ii) extrusion-based 3D printing (e.g., fused
enhancing their antibacterial efficacy. Testing revealed deposition modeling and direct ink writing), and (iii)
that FSC/EPL exhibited potent antibacterial activity light-based 3D printing (e.g., stereolithography and digital
against E. coli and S. aureus without the use of antibiotics, light processing [DLP]).
thereby hindering bacterial growth and mitigating the
risk of antibiotic resistance. In another study, Li et al. 181,183 5.1. Inkjet 3D printing
introduced an effective technique for chemically bonding Inkjet printing is a liquid-phase deposition technique
pre-modified TiO and TiO @Ag nanoparticles onto that operates by ejecting picoliter-scale droplets from a
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FS fabrics. The modified fabrics, particularly those nozzle to precisely coat a substrate. 194-196 As early as 2006,
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enhanced with TiO @Ag nanoparticles, exhibited robust Limem et al., from the group led by Kaplan, utilized
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UV-blocking capabilities and antibacterial activity against inkjet printing to deposit a 0.6% (w/w) FS solution onto
Volume 4 Issue 2 (2025) 13 doi: 10.36922/MSAM025130020