RESUMEN

The utilization of implantable devices beseeches highly invasive surgeries considering the adversaries in the insertion of large, impliable devices through the body channels, which necessitate the development of implantable devices using biocompatible shape memory polymers. Silk displays prodigious heterogeneity in its genetic structure and physical properties in accordance with the spinning and storage process, where proteins undergo folding and unfolding. The stimuli-responsive nature of silk can be explained with the help of the structural morphology and composition of the material, where the hydrogen bonds in ß-sheet domains and amorphous region act as switch points and net points, respectively. This review provides a primary attempt to enswathe all the literature available to date on the stimuli-responsive nature of silk and silk-based materials as a natural and biodegradable alternative for commercially used synthetic shape memory materials taking their elastomeric nature and reduction in glass transition temperature into account. Further constitutive model using the continuum approach has been utilized to explain the anisotropic elasticity damping effect and plastic deformation based on the α-helix chains, ß-sheets, and ß-spiral structures. The practicability to develop biomedical devices such as patient-specific-injectable scaffolds, drug carriers, and artificial muscles has been encompassed in this article.

Asunto(s)

Fibroínas , Seda , Humanos , Seda/química , Fibroínas/química , Materiales Biocompatibles/química

RESUMEN

According to World Health Organization (WHO), on average, 0.5 Kg of hazardous waste is generated per bed every day in high-income countries. The adverse effects imposed by synthetic materials and chemicals on the environment and humankind have urged researchers to explore greener technologies and materials. Amidst of all the natural fibers, silk fibroin (SF), by virtue of its superior toughness (6 × 104∼16 × 104 J/kg), tensile strength (47.2-67.7 MPa), tunable biodegradability, excellent Young's modulus (1.9-3.9 GPa), presence of functional groups, ease of processing, and biocompatibility has garnered an enormous amount of scientific interests. The use of silk fibroin conjoint with purely natural materials can be an excellent solution for the adverse effects of chemical-based treatment techniques. Considering this noteworthiness, vigorous research is going on in silk-based biomaterials, and it is opening up new vistas of opportunities. This review enswathes the structural aspects of silk fibroin along with its potency to form composites with other natural materials, such as curcumin, keratin, alginate, hydroxyapatite, hyaluronic acid, and cellulose, that can replace the conventionally used synthetic materials, providing a sustainable pathway to biomedical engineering. It was observed that a large amount of polar functional moieties present on the silk fibroin surface enables them to compatibilize easily with the natural additives. The conjunction of silk with natural additives initiates synergistic interactions that mitigate the limitations offered by individual units as well as enhance the applicability of materials. Further the current status and challenges in the commercialization of silk-based biomedical devices are discussed.

Asunto(s)

Fibroínas , Fibroínas/química , Seda/química , Materiales Biocompatibles/química , Regeneración , Atención a la Salud

RESUMEN

The emergence of COVID-19 pandemic has severely affected human health and world economies. According to WHO guidelines, continuous use of face mask is mandatory for personal protection for restricting the spread of bacteria and virus. Here, we report a 3-ply cotton-PLA-cotton layered biodegradable face-mask containing encapsulated phytochemicals in the inner-filtration layer. The nano-fibrous PLA filtration layer was fabricated using needleless electrospinning of PLA & phytochemical-based herbal-extracts. This 3-layred face mask exhibits enhanced air permeability with a differential pressure of 35.78 Pa/cm2 and superior bacterial filtration efficiency of 97.9% compared to conventional face masks. Close-packed mesh structure of the nano-fibrous mat results in effective adsorption of particulate matter, aerosol particles, and bacterial targets deep inside the filtration layer. The outer hydrophobic layer of mask exhibited effective blood splash resistance up to a distance of 30 cm, ensuring its utilization for medical practices. Computational analysis of constituent phytochemicals using the LibDock algorithm predicted inhibitory activity of chemicals against the protein structured bacterial sites. The computational analysis projected superior performance of phytochemicals considering the presence of stearic acid, oleic acid, linoleic acid, and Arachidic acid exhibiting structural complementarity to inhibit targeted bacterial interface. Natural cotton fibers and PLA bio-polymer demonstrated promising biodegradable characteristics in the presence of in-house cow-dung based biodegradation slurry. Addition of jaggery to the slurry elevated the biodegradation performance, resulting in increment of change of weight from 07% to 12%. The improved performance was attributed to the increased sucrose content in biodegradation slurry, elevating the bacterial growth in the slurry. An innovative face mask has shown promising results for utilization in day-to-day life and medical frontline workers, considering the post-pandemic environmental impacts.