BOMBYX MORI SILK FIBROIN/ MODIFIED CLAY NANOCOMPOSITES FILMS

Abstract

ilk, is a naturally occurring proteinaceous bio polymer known for its impressive mechanical strengthand lustre produced in fibre form by silkworms and spiders. Silk from worms have been used in high value textiles for thousands of years due to its excellent mechanical strength, vibrant lustre & light weight. Apart from its use in traditional textiles, silk has been used as suture materials for centuries. Silkworm silk is a low-density structural protein, possesses a high content of β sheet or α helices with a core domain of random coils making it more crystalline and robust in nature. [2]. The Bombyx mori protein fiber is a composite material comprising a semi-crystalline silk core (i.e., silk fibroin), which is mainly responsible for the load-bearing capacity, and an outer layer of sericin, which functions as a gumming agent.*3+. Being nature’s own gift, it is an excellent biocompatible material. Recently, regenerated silk fibroin (RSF) solutions have been used to form a variety of biomaterials, in form of gels, sponges and films, for medical applications. The application includes wound healing and in tissue engineering of bone, cartilage, tendon and ligament tissues for its bioresorbable attributes. [4] It is also tuneable to biodegradation having least host immune response. As an intriguing and abundant biomaterial, silk also offers exquisite mechanical, optical, and electrical properties that are advantageous toward the development of biocompatible electronic devices, biomedical diagnosis, as well 5 as human–machine interfaces. It also finds its application in high-performance bio-integrated electronics, computing technologies [5]. Montmorillonite nano clay are a family of sheet like nano fillers belonging to the family of 2:1 layered silicate consisting of two-dimensionallayers. A central octahedral sheet of alumina or magnesia is fused intotwo external silica tetrahedron so that the oxygen ions of octahedralsheet pertain to tetrahedral sheets. The thickness of layers is ca. 1 nm andthe lateral dimensions of the layers vary from several tens of nanometersto several micrometers and even larger. These layers will form stackswith van der Waals gaps between “interlayers” or “inter-galleries”. Superior mechanical & physical properties of property of nano fillers may be attributed to their extremely high surface area. Recently, ecological concerns have initiated a momentum of research towards the development and discovery of “Green” or “biodegradable” materials over synthetic ones.Bio nanocomposites are a class of composites made of nanosized materials. They contain the constituent of biological origin and particles with at least one dimension in the range of 1–100 nm.[6]. So, in this study, we have preparedSilk fibroin/ Montmorillonite nanocomposite films, where the nano clay is chemically modified to give it additional functionality. Silk films along with their robust mechanical properties, bio compatibility & optical transparency is a potential biomaterial which can integrate electronics, optics and human health monitoring.