Research articles authored by NIIST researchers published in 2020 http://localhost:8080/xmlui/handle/123456789/3466 2026-04-06T11:35:44Z 2026-04-06T11:35:44Z Jibin, K Prasad, J S Saranya, G Shenoy, S Maiti, K K Jayasree, R S http://localhost:8080/xmlui/handle/123456789/4463 2023-04-10T10:06:07Z 2020-01-01T00:00:00Z

Title: Optically Controlled Hybrid Metamaterial of Plasmonic Spiky Gold Inbuilt Graphene Sheets for Bimodal Imaging Guided Multimodal Therapy Authors: Jibin, K; Prasad, J S; Saranya, G; Shenoy, S; Maiti, K K; Jayasree, R S Abstract: The development of multifunctional molecular diagnostic platforms for concordant visualization and treatment of diseases with high sensitivity and resolution has recently become a crucial strategy in cancer management. Thus, engineering functional metamaterials with high therapeutic and imaging capabilities to elucidate diseases from morphological behaviors to physiological mechanisms is an unmet need in the current scenario. Here, we report the design of a unique hybrid plasmonic nanoarchitecture, for targeted multiple photo-therapies of breast cancer by simultaneous real time monitoring through fluorescence and surface enhanced Raman scattering (SERS) techniques. The nanoframework consists of plasmonic gold-graphene hybrids tethered with folic acid ligated chitosan modified photosensitizer (PpIX) to afford target specific localized photothermal and photodynamic therapy. The hybrid vehicle also served as an excellent nanocarrier for efficient loading and stimuli responsive release of the chemotherapeutic drug doxorubicin (DOX) to enhance the therapeutic efficacy, thereby forming a trimodal nanomedicine against cancer. The cytotoxic effects induced by the cumulative action of triplet therapeutic tools were visualized through both fluorescence and SERS imaging channels. Moreover, it also generated synchronized therapeutic effects resulting in the effective regression of tumor volume without propagating any toxic effect to other organs of the animals. Taken together, by virtue of strong light-matter interactions, our nanoprobe showed enhanced photoadsorption which facilitate the amplified light reactive therapeutic and imaging efficacies along with targeted and enhanced chemotherapy, both in vitro and in vivo, which may offer a promising outcome in clinical research.

2020-01-01T00:00:00Z Karthyani, S Pandey, A Devendra, L P http://localhost:8080/xmlui/handle/123456789/4462 2023-04-10T10:02:00Z 2020-05-18T00:00:00Z

Title: Delignification of Cotton Stalks Using Sodium Cumene Sulfonate for Bioethanol Production Authors: Karthyani, S; Pandey, A; Devendra, L P Abstract: The objective of this study was to evaluate the effect of hydrotropic delignification of cotton stalk on sugar release performance for bioethanol production. In this study, different alkyl benzene sulfonates were screened to select the best pretreatment agent, and the effectiveness of pretreatment was evaluated by enzymatic saccharification. Sodium cumene sulfonate was found to be the best hydrotropic agent in terms of reducing sugar yield. Parameters such as hydrotrope concentration, biomass loading and incubation time were optimized by adopting a central composite design. Under optimized pretreatment conditions, 0.211 g reducing sugar/g of dry biomass was obtained. Reusability of aqueous hydrotrope solution was also demonstrated.

2020-05-18T00:00:00Z Das, P P Samanta, S Blom, D A Pramanik, S Devi, P S Vogt, T Lee, Y http://localhost:8080/xmlui/handle/123456789/4320 2023-04-05T14:36:43Z 2020-01-01T00:00:00Z

Title: Pressure-induced Assemblies and Structures of Graphitic-carbon Sheet Encapsulated Au Nanoparticles Authors: Das, P P; Samanta, S; Blom, D A; Pramanik, S; Devi, P S; Vogt, T; Lee, Y Abstract: A novel strategy of using hydrostatic pressures to synthesize gold–carbon (Au–C) nanohybrid materials is explored. The stable face-centered-cubic (fcc) Au undergoes a structural phase transition to a mixture of primitive orthorhombic and cubic phases as the carbon phase acquires a highly ordered onion-like carbon (OLC) structure which encapsulates the Au nanoparticles, thereby exerting an additional pressure. Increasing the pressure results in a one dimensional (1-D) chain-like structure with the primitive cubic Au nanoparticles contained in an amorphous carbon matrix. The OLC structure allows the formation of quenchable Au nanoparticle phases with the primitive close packing and Au–C hybrids with new mesoscopic structures. Under pressure, we observe the formation of a hybrid material composed of a poorly conducting matrix made of amorphous carbon and conducting OLC-encapsulated Au nanoparticles. The electrical conductivity of this hybrid material under pressure reveals a percolation threshold. We present a new synthesis approach to explore the interplay between atomic and mesoscopic structures and the electrical conductivity of metal hybrid structures.

2020-01-01T00:00:00Z Hanna, B Manuraj, M Surendran, K P Unni, K N N http://localhost:8080/xmlui/handle/123456789/4313 2023-04-05T10:35:19Z 2020-08-01T00:00:00Z

Title: Opto-electronic Properties of Solution-processed Zinc Oxide Thin Films: Role of Solvents and Doping Authors: Hanna, B; Manuraj, M; Surendran, K P; Unni, K N N Abstract: Undoped zinc oxide (ZnO) and nitrogen-doped zinc oxide (NZO) thin films were prepared on transparent conducting oxide-coated glass substrates by employing sol–gel technique. The effect of different solvents and nitrogen doping on the optical, structural, and electrical properties was investigated by UV–visible absorption spectroscopy, atomic force microscopy (AFM), X-ray diffraction (XRD), profilometry, and Hall effect studies. ZnO films yielded transmittance above 85% and the bandgap of ZnO thin films decreased with doping. XRD pattern confirmed hexagonal wurtzite structure of ZnO. NZO thin films were found to be in the nano-thin film phase with thickness of 40 nm. Hall effect studies yielded carrier concentration of 1.2 × 1015 cm−3 and 2.03 × 1014 cm−3, respectively, for undoped and doped ZnO thin films. The changes in vibrational modes of ZnO due to nitrogen doping were detected using Fourier transform infrared (FTIR) analysis. It was found that p-type doping, leading to an improved surface morphology, led to a reduction in optical bandgap and an increased charge carrier mobility. The choice of the solvent was found to have a profound influence on the surface morphology, optical bandgap, tail states distribution, and charge carrier mobility.

2020-08-01T00:00:00Z