http://dspace.dtu.ac.in:8080/jspui/handle/123456789/19 2026-04-28T04:03:39Z http://dspace.dtu.ac.in:8080/jspui/handle/repository/20684 Title: GREEN SYNTHESIS AND CHARACTERISATION OF COPPER OXIDE NANOPARTICLES USING PSIDUM GUAJAVA LEAF EXTRACT Authors: VARUGHESE, AMMU Abstract: Green synthesis of nanoparticles has gained enormous attention in today’s world due to ongoing demand to develop sustainable, safe, economical and eco-friendly process for synthesizing a wide variety of materials including metal/metal oxides nanoparticles, hybrid and bioinspired materials. In the current study, green synthesis of copper oxide (CuO) nanoparticles (NPs) has been carried out by utilising extract of psidium guajava leaf as capping agent and cupric acetate as metal precursor. The biosynthesized nanoparticles were characterized utilizing wide assortment of methodologies for example powder X-beam diffraction (PXRD), FTIR, TGA and HRTEM. The PXRD result confirms the synthesis of CuO NPs in pure phase having monoclinic symmetry. The average particle size using PXRD was found out to be ~33nm 2020-08-01T00:00:00Z http://dspace.dtu.ac.in:8080/jspui/handle/repository/19447 Title: STUDY ON UTILIZATION OF AGRO-WASTE AS SOURCE FOR HEPARIN Authors: JENA, SAIKRUSHNA Abstract: Heparin is a highly sulphated and most negatively charged natural biopolymer belonging to the glycosaminoglycan (GAG) family. This is about a 100-year-old anticoagulant drug. This is equally important for non-anticoagulant diseases also and is the reason for the recent burgeoning of interest in the molecule. Heparin has been isolated from both animal and non-animal sources; however, porcine mucosa remains the FDA-approved source for heparin. For the synthesis, chemical, chemoenzymatic, and biotechnological approaches have been studied. In recent times, the focus is more on synthesizing LMWH, ULMWH, and bioengineered heparins. A sustained and healthy society needs proper utilization of the waste material to deal with the increasing pollution rate. Several works are successfully done on this note, and till now, several strategies have been developed for the production of bio-chemicals from biological waste. In other words, value has been added to the waste materials. The biochemicals like starch, maltose, amylose, etc. have been isolated from the biological waste. These biomolecules may be used as a source of heparin synthesis to avoid the synthetic dependency of living organisms. Here in this work, I have explored the possibilities of biomolecules isolated from waste as source of heparin synthesis. 2021-07-01T00:00:00Z http://dspace.dtu.ac.in:8080/jspui/handle/repository/18808 Title: BOMBYX MORI SILK FIBROIN/ MODIFIED CLAY NANOCOMPOSITES FILMS Authors: BOSE, UTSAV 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. 2020-12-01T00:00:00Z http://dspace.dtu.ac.in:8080/jspui/handle/repository/18794 Title: RHEOLOGICAL STUDY OF NON- MULBERRY SILK (TASAR) AND GELATIN BLEND SOLUTION Authors: PRITI Abstract: I studied the impacts of blending Antheraea mylitta silk fibroin solution (10% w/v) with gelatin solution (20% w/v) using formic acid as a solvent in this study. The viscoelastic properties of blends of different ratios such as S0G10, S2G8, S3G7, S5G5, and S10G0 were investigated. To confirm miscibility of pure polymeric components in blend solutions, optical microscopy, thermogravimetric analysis and differential scanning calorimetry were used to analyze surface morphology and thermal properties of the blend solution. Blend solutions with varying shear rates in the range of 0.01-500 s-1 were studied for steady shear behaviour. The dynamic rheological experiment including amplitude and frequency sweeps were performed. Blending gelatin with silk fibroin reduced overall viscosity when compared to pure silk fibroin solution, demonstrating shear thinning behaviour in the applied shear range, according to studies. All of the solutions deviated from the Cox-Merz rule, with the exception of pure gelatin, which obeyed it. A frequency sweep research was carried out with a specific proportion of strain applied. The steady and oscillatory experiments revealed a shift in the solution's behaviour from viscous fluid (as in gelatin) and solid (as in silk fibroin) to viscoelastic. The samples were studied to time-dependent tests such as structural recovery, creep recovery, and stress relaxation. It was discovered that the amount of gelatin in a blend effects its structural recovery. The samples were studied to time-dependent tests such as structural recovery, creep recovery, and stress relaxation. It was discovered that the amount of gelatin in a blend effects its structural recovery. The properties of blend solutions can be tailored by changing parameters such as time, shear rate, angular frequency, and blend ratios to achieve desired features for specific end use applications such as packaging, tissue engineering, medical textile, and filtration, according to such rheological analysis. 2021-07-01T00:00:00Z