Application of Silk-Fibroin-Based Hydrogels in Tissue Engineering

Abstract

Silk fibroin (SF) is an excellent protein-based biomaterial produced by the degumming and purification of silk from cocoons of the Bombyx mori through alkali or enzymatic treatments. SF exhibits excellent biological properties, such as mechanical properties, biocompatibility, biodegradability, bioabsorbability, low immunogenicity, and tunability, making it a versatile material widely applied in biological fields, particularly in tissue engineering. In tissue engineering, SF is often fabricated into hydrogel form, with the advantages of added materials. SF hydrogels have mostly been studied for their use in tissue regeneration by enhancing cell activity at the tissue defect site or counteracting tissue-damage-related factors. This review focuses on SF hydrogels, firstly summarizing the fabrication and properties of SF and SF hydrogels and then detailing the regenerative effects of SF hydrogels as scaffolds in cartilage, bone, skin, cornea, teeth, and eardrum in recent years.

Applications of Silk Fibroin in Human and Veterinary Medicine

“…Administration of GFs alone may result in a number of undesirable effects, such as the formation of ectopic bones. Such administration of isolated GF may also result in therapy failure, due to the short half-life of these proteins [55]. So, in practice, for the effective carriage of BMP-2, SF hydrogel was fabricated using the electrospun poly(ε-caprolactone) (PCL) nanofibre mesh tubing.…”

Silk fibroin increases the elasticity of alginate-gelatin hydrogels and regulates cardiac cell contractile function in cardiac bioinks

“…In its regenerated form, SF molecules interact through non-covalent bonds such as hydrogen bonding, between the αhelices and β-sheets (as reported in supplementary figure 1) [1,16]. Alternatively, SF can be added to other formulations to have better control over their mechanical properties and degradation rates [17,18], which can create new hydrogen bonding and electrostatic interactions. For instance, sodium Alg and SF blend through intermolecular hydrogen bonds, which occur between the carboxyl group (COO-) of Alg and the amide group of SF (-NH 2 ), the amide group (both the C=O and -NH 2 ) of SF and -OH molecules in Alg polymer.…”

Microfibre-Functionalised Silk Hydrogels

“…The use of biopolymers is particularly prominent in wound care, and interesting platforms are emerging, including, for example, cellulose-based hydrogels doped with chitosan nanoparticles [ 8 ] or drug-loaded polydopamine for the treatment of skin wounds [ 9 ]. Silk fibroin, derived from Bombyx mori silkworms, has also garnered significant interest among tissue engineers, in part due to its biocompatibility, biodegradation and resemblance to the natural extracellular matrix (ECM) (reviewed in [ 10 , 11 ]). For example, silk hydrogels can mimic the viscoelastic properties of tissues [ 12 ], making them an interesting platform for further exploration of their use in cell attachment and growth as well as in the scaffold fabrication required for more advanced tissue engineering applications.…”

“…To date, B. mori silk has been the material of choice for silk-mediated tissue engineering for several reasons. This preference for B. mori silk is due, at least in part, to the robust supply chain of B. mori raw materials, the ease with which the fibre can be reverse-engineered into liquid silk and the clinical approval and use of B. mori silk in humans, both as its native spun fibre and its processed formats [ 11 , 17 ]. However, many different silks exist in nature; indeed, silk has arisen at least 23 times via independent evolutionary events [ 18 ].…”