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161.
Single crystals of benzophenone-2-furoyl hydrazone are grown by slow evaporation solution growth technique from ethanol at room temperature. It belongs to monoclinic system with the space group P21/c and the cell parameters are, a = 6.1631(3) Å, b = 13.1397(8) Å, c = 18.0030(11) Å and V = 1457.72(14) Å3. NMR spectral studies reveal the structure and powder XRD indicates the crystallinity of the specimen. The characteristic functional groups present in the molecule are confirmed by Fourier transform infrared spectroscopy. The crystals are transparent in the visible region having a lower optical cut-off at ∼406 nm and the band gap energies are estimated by the application of Kubelka–Munk algorithm. Thermal analysis by TG/DTA indicates the stability of the material. The scanning electron microscopy studies reveal the surface morphology of the as-grown crystal. Theoretical calculations were performed using Hartree–Fock method with 6-31G(d,p) as the basis set for to derive the optimized geometry, dipole moment and first-order molecular hyperpolarizability (β) values. 相似文献
162.
163.
Subbiah RP Lee H Veerapandian M Sadhasivam S Seo SW Yun K 《Analytical and bioanalytical chemistry》2011,400(2):547-560
A bio-nanofilm consisting of a tetrad nanomaterial (nanotubes, nanoparticles, DNA, polymer) was fabricated utilizing in situ
reduction and noncovalent interactions and it displayed effective antibacterial activity and biocompatibility. This bio-nanofilm
was composed of homogenous silver nanoparticles (AgNPs) coated on single-walled carbon nanotubes (SWCNTs), which were later
hybridized with DNA and stabilized in poly(vinyl alcohol) (PVA) in the presence of a surfactant with the aid of ultrasonication.
Electron microscopy and bio-AFM (atomic force microscopy) images were used to assess the morphology of the nanocomposite (NC)
structure. Functionalization and fabrication were examined using FT–Raman spectroscopy by analyzing the functional changes
in the bio-nanofilm before and after fabrication. UV–visible spectroscopy and X-ray powder diffraction (XRD) confirmed that
AgNPs were present in the final NC on the basis of its surface plasmon resonance (370 nm) and crystal planes. Thermal gravimetric
analysis was used to measure the percentage weight loss of SWCNT (17.5%) and final SWCNT-AgNPs-DNA/PVA (47.7%). The antimicrobial
efficiency of the bio-nanofilm was evaluated against major pathogenic organisms. Bactericidal ratios, zone of inhibition,
and minimum inhibitory concentration were examined against gram positive and gram negative bacteria. A preliminary cytotoxicity
analysis was conducted using A549 lung cancer cells and IMR-90 fibroblast cells. Confocal laser microscopy, bio-AFM, and field
emission scanning electron microscopy (FE-SEM) images demonstrated that the NCs were successfully taken up by the cells. These
combined results indicate that this bio-nanofilm was biocompatible and displayed antimicrobial activity. Thus, this novel
bio-nanofilm holds great promise for use as a multifunctional tool in burn therapy, tissue engineering, and other biomedical
applications. 相似文献
164.
Shanmugarajan A Alwarappan S Rajendran L 《The journal of physical chemistry. A》2011,115(17):4299-4306
A mathematical model of trienzyme biosensor at an internal diffusion limitation for a non-steady-state condition has been developed. The model is based on diffusion equations containing a linear term related to Michaelis-Menten kinetics of the enzymatic reaction. Analytical expressions of concentrations and current of compounds in trienzyme membrane are derived. An excellent agreement with simulation data is noted. When time tends to infinity, the analytical expression of non-steady-state concentration and current approaches the steady-state value, thereby confirming the validity of the mathematical analysis. Furthermore, in this work we employ the complex inversion formula to solve the boundary value problem. 相似文献
165.
Lamya H. Al-Wahaibi Mario A. Macías Olivier Blacque Luke S. Zondagh Jacques Joubert Subbiah Thamotharan María Judith Percino Ahmed A. B. Mohamed Ali A. El-Emam 《Molecules (Basel, Switzerland)》2022,27(21)
Structural analysis and docking studies of three adamantane-linked 1,2,4-triazole N-Mannich bases (1–3) are presented. Compounds 1, 2 and 3 crystallized in the monoclinic P21/c, P21 and P21/n space groups, respectively. Crystal packing of 1 was stabilized by intermolecular C-H⋯O interactions, whereas compounds 2 and 3 were stabilized through intermolecular C-H⋯N, C-H⋯S and C-H⋯π interactions. The energy frameworks for crystal structures of 1–3 were described. The substituent effect on the intermolecular interactions and their contributions were described on the basis of Hirshfeld surface analyses. The 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) inhibition potential, pharmacokinetic and toxicity profiles of compounds 1–3 were determined using in silico techniques. Molecular docking of the compounds into the 11β-HSD1 active site showed comparable binding affinity scores (−7.50 to −8.92 kcal/mol) to the 11β-HSD1 co-crystallized ligand 4YQ (−8.48 kcal/mol, 11β-HSD1 IC50 = 9.9 nM). The compounds interacted with key active site residues, namely Ser170 and Tyr183, via strong hydrogen bond interactions. The predicted pharmacokinetic and toxicity profiles of the compounds were assessed, and were found to exhibit excellent ADMET potential. 相似文献