What Molecular and Structural Properties Make Tussah Silk Fabric a Frontrunner in Biomedical and Advanced Composite Applications?

Tussah silk, a non-mulberry silk variant spun by wild Antheraea silkworms, is increasingly recognized as a transformative material in biomedical engineering and high-performance composites. Its unique molecular architecture, characterized by a high proportion of alanine-rich β-sheet crystallites interspersed with glycine-dominated amorphous regions, grants it exceptional mechanical adaptability and biocompatibility—a combination rarely found in natural fibers. Recent Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analyses reveal that Tussah silk’s fibroin exhibits a 15–20% higher crystallinity index compared to Bombyx mori silk, enhancing its load-bearing capacity while retaining elasticity. This structural duality is critical for applications such as surgical sutures, where tensile strength (up to 500 MPa) and flexibility must coexist to withstand dynamic physiological environments.

In biomedical contexts, Tussah silk’s low immunogenicity and slow degradation rate (6–24 months in vivo) make it ideal for tissue engineering scaffolds. Unlike synthetic polymers, its degradation byproducts—primarily amino acids—are non-toxic and integrate seamlessly into metabolic pathways. Research published in Biomaterials Science demonstrates that Tussah silk scaffolds seeded with mesenchymal stem cells promote osteogenesis due to the fiber’s inherent calcium-binding sites, a property absent in most plant-based textiles. Furthermore, its innate antibacterial activity, attributed to residual sericin peptides, reduces post-implant infection risks without requiring chemical coatings.

For advanced composites, Tussah silk’s hierarchical structure—ranging from nanofibrils to macro-scale yarns—enables tailored reinforcement in epoxy or polylactic acid (PLA) matrices. Atomic force microscopy (AFM) studies show that its fibers’ rough surface topography improves interfacial adhesion with polymers, increasing composite flexural strength by 30–40% compared to glass fiber counterparts. Aerospace and automotive industries are exploring Tussah silk-carbon fiber hybrids to create lightweight, impact-resistant panels that meet stringent flammability standards (UL94 V-0 rating), as the silk’s nitrogen-containing proteins inherently suppress combustion.

Processing innovations further amplify its utility. Electrospinning techniques produce Tussah silk nanofibers (50–200 nm diameter) with tunable porosity for air filtration systems capable of capturing PM0.3 particulates at 99.97% efficiency. Meanwhile, enzymatic biofinishing allows selective removal of sericin without damaging fibroin integrity, a breakthrough for creating ultra-thin, conductive silk films used in flexible biosensors. As circular manufacturing gains traction, Tussah silk’s compatibility with ionic liquid solvents enables closed-loop recycling—a stark contrast to petroleum-derived Kevlar or Nylon.

The convergence of Tussah silk’s innate biochemistry, structural versatility, and eco-efficient processing cements its role in next-generation material science, bridging the gap between ecological sustainability and cutting-edge technological demand.