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81.
Arya Ghosh Subash C.B. Gopinath Sayeed Mohammad Firdous Santheraleka Ramanathan 《印度化学会志》2022,99(8):100604
Human Mammary Tumor Virus (HMTV) or Mouse Mammary Tumor Virus holds similarity as an endogenous onco-retrovirus belongs to retroviridae family, predominantly infects the epithelial cell of human as well as mouse. With the recognition of nano-biosensor in nanotechnology, ideal interdigitated electrode (IDE) was genuinely performed for HMTV detection. Aluminium enriched IDE (AlIDE) was fabricated for high performance detection with a cost-effective photolithography technique. In this research, (3-glycidyloxypropyl) trimethoxysilane refined platform was selected to detect the conductivity with HMTV target DNA interaction on the designed AlIDE. Strong binding affinity of streptavidin-biotin with target DNA enhanced the sensitivity by empowering higher number of HMTV probe and target complementation on sensing surface. Furthermore, the target DNA was immobilized on probe modified AlIDE and a quantitative value of 100 aM attained as a lowest detection. A linear with dose-dependent duplex formation was shown with the regression coefficient value of 0.964. Negative control has shown insignificant detection at 10 pM, which justifies the higher fold discrimination with specificity. The excellence of AlIDE performance in detection of HMTV may pave the way for more verification on other diseases. 相似文献
82.
Anindita Chatterjee 《印度化学会志》2022,99(9):100653
Synthesis of pure Zinc oxide (ZnO), Copper oxide (CuO) nanoparticles (NPs) and their (ZnO/CuO) nanocomposites (NCs) in 1:1 M ratio were successfully prepared by co-precipitation method. The structural properties of the as synthesized nanoparticles and nanocomposite materials were investigated using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) techniques. Optical band-gap studies were done using UV–Visible absorption spectroscopy. Photovoltaic properties of pure ZnO NPs, CuO NPs and ZnO/CuO NCs coated over a single-crystalline silicon solar cell were carried out to compare improvement of light-conversion efficiency in coated solar cell. The maximum light conversion efficiencies were found to be of 8.02% for CuO (3 mg/ml concentration) and 7.28% for ZnO NPs (3 mg/ml concentration), whereas that of mixed metal nanocomposite CuO/ZnO NCs was found to be 7.62%. at very low concentration of 1 mg/ml. This indicates with low concentration of mixed metal NCs an improvement in light efficiency can be obtained. The enhancement in efficiency could be due to formation of p - n heterojunction by CuO/ZnO NCs composites which enhances the number of electrons and holes participating in conduction on the surface. 相似文献
83.
MSc. Adukkadan N. Ramya Jayadev S. Arya MSc Murali Madhukrishnan MSc. Shanmughan Shamjith Murukan S. Vidyalekshmi PhD. Kaustabh K. Maiti 《化学:亚洲杂志》2021,16(5):409-422
In accordance with the recent studies, Raman spectroscopy is well experimented as a highly sensitive analytical and imaging technique in biomedical research, mainly for various disease diagnosis including cancer. In comparison with other imaging modalities, Raman spectroscopy facilitate numerous assistances owing to its low background signal, immense spatial resolution, high chemical specificity, multiplexing capability, excellent photo stability and non-invasive detection capability. In cancer diagnosis Raman imaging intervened as a promising investigative tool to provide molecular level information to differentiate the cancerous vs non-cancerous cells, tissues and even in body fluids. Anciently, spontaneous Raman scattering is very feeble due to its low signal intensity and long acquisition time but new advanced techniques like coherent Raman scattering (CRS) and surface enhanced Raman scattering (SERS) gradually superseded these issues. So, the present review focuses on the recent developments and applications of Raman spectroscopy-based imaging techniques for cancer diagnosis. 相似文献
84.
Kanigel A Chatterjee U Randeria M Norman MR Souma S Shi M Li ZZ Raffy H Campuzano JC 《Physical review letters》2007,99(15):157001
Angle resolved photoemission on underdoped Bi2Sr2CaCu2O8 reveals that the magnitude and d-wave anisotropy of the superconducting state energy gap are independent of temperature all the way up to T{c}. This lack of T variation of the entire k-dependent gap is in marked contrast to mean field theory. At T{c} the point nodes of the d-wave gap abruptly expand into finite length "Fermi arcs." This change occurs within the width of the resistive transition, and thus the Fermi arcs are not simply thermally broadened nodes but rather a unique signature of the pseudogap phase. 相似文献
85.
Stereospecific Formal [3+2] Dipolar Cycloaddition of Cyclopropanes with Nitrosoarenes: An Approach to Isoxazolidines
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Shyamal Chakrabarty Dr. Indranil Chatterjee Birgit Wibbeling Dr. Constantin Gabriel Daniliuc Prof. Dr. Armido Studer 《Angewandte Chemie (International ed. in English)》2014,53(23):5964-5968
The MgBr2‐catalyzed formal [3+2] cycloaddition of donor–acceptor activated cyclopropanes with nitrosoarenes offers a novel approach to various structurally diverse isoxazolidines. The reactions, which are experimentally easy to conduct, occur with complete stereospecificity and perfect control of regioselectivity. Product isoxazolidines can be readily transformed into α‐amino lactones by reductive or decarboxylative N? O cleavage and subsequent lactonisation, and the N‐aryl bond cleavage is also possible under oxidative conditions. 相似文献
86.
Debabrata Chatterjee Swapan Kumar Moulik Lingamallu Giribabu Ravi Kumar Kanaparthi 《Transition Metal Chemistry》2014,39(6):641-646
The Fe(III) complex, [FeIII(HQS)3] (HQS = 8-hydroxyquinoline-5-sulfonic acid), is found to effect sensitization of the large band gap semiconductor, TiO2. The role of interfacial electron transfer in sensitization of TiO2 nanoparticles by surface adsorbed [FeIII(HQS)3] was studied using femtosecond time scale transient absorption spectroscopy. Electron injection has been confirmed by direct detection of the electron in the conduction band. A TiO2-based dye-sensitized solar cell (DSSC) was fabricated using [FeIII(HQS)3] as a sensitizer, and the resulting DSSC exhibited an open-circuit voltage value of 425 mV. The value of the short-circuit photocurrent was found to be 2.5 mA/cm2. The solar to electric power conversion efficiency of the [FeIII(HQS)3] sensitized TiO2-based DSSC device was 0.75 %. The results are discussed in the context of sensitization of TiO2 by other Fe(II)-dye complexes. 相似文献
87.
Copolymers obtained by the condensation of p-bromoaniline, formaldehyde, and p-cresol have been separated into five fractions by a fractional precipitation method. Some of these copolymers showed characteristic titration curves in non-aqueous media. The titration curves indicated a series of breaks which bear integral relations to each other. These features have been interpreted in terms of homoconjugation, intramolecular hydrogen bonding, and composition of the copolymers. 相似文献
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90.
Venkata Reddy Regalla RamaKrishnam Raju Addada Venkat Swami Puli Abhishek S. Saxena Anindita Chatterjee 《Tetrahedron letters》2017,58(24):2344-2346
A short and efficient method for the stereoselective synthesis of Dendrodolide L has been developed from inexpensive and commercially available starting material. This convergent synthesis utilizes Jacobsen kinetic resolution, regioselective ring-opening of epoxide and Yamaguchi macrolactonization as key steps. 相似文献