Browsing by Author "Shanmuga Sundari, S"

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ANTIBACTERIAL AND ANTICANCER ACTIVITY (PANC-1) OF GREEN SYNTHESIZED COPPER OXIDE NANOPARTICLES FROM CATHARANTHUS ROSEUS
(Taylor and Francis Ltd, 2024) Karthika, S; Kanchana, P; Prabha Devi, B; Shanmuga Sundari, S
Copper oxide nanoparticle was biosynthesized using the petals of Catharanthus roseus, and it was found to exhibit anticancer activity in a human pancreatic cell line (PANC-1). The obtained nanoparticles were characterized using XRD, FTIR, FESEM, and TEM techniques. XRD confirms the coexistence of CuO and Cu2O nanoparticles with an average grain size of 15 nm. FTIR spectra possess bands that indicate the formation of copper oxide nanoparticles. FESEM and TEM show spherical shape morphology with an average particle size of 19.6 nm to 32.6 nm. The synthesized copper oxide nanoparticles were tested for antibacterial activity, and the gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa showed a better zone of inhibition than standard streptomycin. The copper oxide nanoparticle was tested for anticancer activity in the PANC-1 line, and the results confirm that cells undergo cell shrinkage in the cytoplasm, which suggested the cytotoxic behavior. The viability of cells was evaluated by an inverted phase contrast microscope followed by the MTT assay method.
ANTIBACTERIAL AND ANTICANCER ACTIVITY (PANC-1) OF GREEN SYNTHESIZED COPPER OXIDE NANOPARTICLES FROM CATHARANTHUS ROSEUS
(Taylor & Francis Online, 2023-07-03) Karthika, S; Kanchana, P; Prabha Devi, B; Shanmuga Sundari, S
Copper oxide nanoparticle was biosynthesized using the petals of Catharanthus roseus, and it was found to exhibit anticancer activity in a human pancreatic cell line (PANC-1). The obtained nanoparticles were characterized using XRD, FTIR, FESEM, and TEM techniques. XRD confirms the coexistence of CuO and Cu2O nanoparticles with an average grain size of 15 nm. FTIR spectra possess bands that indicate the formation of copper oxide nanoparticles. FESEM and TEM show spherical shape morphology with an average particle size of 19.6 nm to 32.6 nm. The synthesized copper oxide nanoparticles were tested for antibacterial activity, and the gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa showed a better zone of inhibition than standard streptomycin. The copper oxide nanoparticle was tested for anticancer activity in the PANC-1 line, and the results confirm that cells undergo cell shrinkage in the cytoplasm, which suggested the cytotoxic behavior. The viability of cells was evaluated by an inverted phase contrast microscope followed by the MTT assay method.
BIOSYNTHETIC GREENER MOVE TOWARDS NANOSIZED SILVER BY DIOSPYROS MONTANA LEAF EXTRACT AND THEIR ANTIMICROBIAL AND ANTIOXIDANT ACTIVITIES
(Blue Eyes Intelligence Engineering and Sciences Publication (BEIESP), 2020-01-05) Kanchana, P; Arunadevi, N; Hemapriya, V; Shanmuga Sundari, S; Prabha Devi, B
Synthesis of nanomaterials by eco-friendly method is being exploited by chemists because of several advantages over other conventional techniques. The current investigation reports the green approach for Diospyros Montana(DM) silver nanosized particles which has high antimicrobial and antioxidant activities. The synthesized nanosized particles were investigated by several techniques such as IR, Ultra violet, X-Ray Diffraction, Transmission Electron Microscope and AFM studies. Crystalline size of the silver nanoparticle is in the range of 47.05 nm which was clear from the powder X-rd studies. The silver nanoparticls prepared were tested for their antimicrobial potential against E.coli, B.subtilis, C.albicans and A.flavus species and was found to reveal excellent activity because of its volume ratio and high surface.The DPPH assy was used to find scavenging activity of free radicals. In this work we report the silver nanoparticles by aqueous Diospyros Montana leaf extract and its potential for free radical scavenging.
DIELECTRIC AND CONDUCTIVITY PROPERTIES OF FLUX GROWN CE DOPED NBT-BT SINGLE CRYSTALS
(Elsevier, 2020-04-01) Shanmuga Sundari, S; Binay, Kumar; Dhanasekaran, R
To study the effect of Ce in the NBT-BT lattice, 0.4 wt% of CeO2 was added to the 0.94(Na0.5Bi0.5TiO3)-0.06BaTiO3, in its morphotropic phase boundary (MPB) composition, and the single crystals were grown by the flux method using Bi2O3 as a flux. The structural studies were carried by the XRD and Raman analyses. The dielectric constants were measured from room temperature to 400 °C for various frequencies in the range of 20 Hz-2 MHz. The anti-ferroelectric temperature region is increasing due to the addition of Ce in the NBT-BT. The maximum value of dielectric loss is also found to decrease from 0.4% to 0.1% due to the Ce addition. The conductivity and impedance analyses were carried out to study the relaxation process of Ce-NBT-BT single crystals.
ENHANCEMENT OF ELECTRICAL AND RADIATION SHIELDING PROPERTIES OF VANADIUM DOPED LITHIUM TELLURO-BORATE (LTB) GLASSES
(Elsevier, 2024) Karthika, S; Shanmuga Sundari, S; Marimuthu, K; Meena, P
Vanadium doped lithium telluro-borate (LTB) glasses of the composition (20-x Li2O-20TeO2-60B2O3-( )V2O5 (x = 0, 0.5, 1, 1.5 and 2 in mol %) were synthesised by melt quenching technique. The structural, optical, physical, electrical and radiation shielding parameters of the prepared glasses were investigated to determine the effect of vanadium in the LTB glass matrix. Density of LTB glasses were found to increases from 2.52 to 2.98 g/cm3 under addition of vanadium oxide and certain density derived structural parameters were studied. XRD pattern confirms the amorphous nature of the pristine and doped LTB glass. FTIR spectra shows the presence of various bonds in the vanadium doped LTB glasses. The direct optical bandgap (Eg) decreases due to the addition of V2O5 and leads to creation of defects in the LTB glasses thereby increasing the Urbach energy (Eu). Physical parameters like refractive index (n), molar refractivity (Rm), reflection loss (Lr), molar electronic polarizability (αm), transmission coefficient (T) and metallization criteria (M) were calculated. The electrical properties including dielectric constant (εʹ), conductivity (σ) and activation energies (Ea) were analysed and observed that Ea decreases under the addition of vanadium to the glass network proving the enhancement in electrical conductivity. Radiation shielding parameters such as MAC, LAC, HVL, TVL, MFP, R, ACS, ECS, Neff, Zeff, and Ceff were calculated using Phy-X/PSD and LTB_2V with the highest V2O5 additive shows enhanced result in gamma radiation shielding.
FACILE SYNTHESIS OF NICKEL DOPED ZNO AND CEO2 NANOCOMPOSITE FOR EFFICIENT PHOTOCATALYTIC DYE DEGRADATION, CATALYTIC REDUCTION AND ANTIMICROBIAL STUDIES
(Taylor and Francis Ltd., 2024-06-01) Kanchana, P; Prabha Devi, B; Sangeedha, A; Hemapriya, V; Shanmuga Sundari, S
The current research work reports on binary Nickel oxide-Zinc oxide (NiO-ZnO) and Nickel oxide-Cerium oxide (NiO-CeO2) nanocomposites synthesis by facile single step in-situ thermal decomposition method and its applications. The structural and morphological studies were examined using various characterization techniques like IR, UV-DRS, XRD and SEM with EDAX studies. The IR bands at 545-533 cm−1 corresponds to M-O stretching vibration. The XRD studies confirms the structural pattern of NiO-ZnO and NiO-CeO2 nanocomposites. SEM with EDAX results reveal the structure, composition and purity of synthesized nanocomposites. The nanocomposites were employed as photocatalyst for degradation of methylene blue and methyl orange dyes and as a catalyst toward 4-nitrophenol reduction. Antibacterial studies against E. coli (Gram-negative) and S. aureus (Gram-positive) bacterial pathogens were carried out using the nanocomposites. The outcomes show 97% efficiency in forty minutes for catalysis and 120 min for dye degradation and a better zone of inhibition in antibacterial studies for NiO-ZnO nanocomposite. The comparative result for both the nanocomposites discloses that the photocatalytic degradation, catalytic and antimicrobial efficiency of NiO-ZnO nanocomposite is more efficient than NiO-CeO2 nanocomposite. The results reveal the outstanding catalytic and dye degradation and antibacterial activity of NiO-ZnO than NiO-CeO2.
GROWTH, STRUCTURAL, DIELECTRIC AND OPTICAL CHARACTERISTICS OF GLYCINE PHOSPHITE SINGLE CRYSTALS
(Elsevier, 2019) Shanmuga Sundari, S; Kanchana, P; Arunadevi, N; Shobana, C
Interesting compounds are formed when glycine reacts with inorganic materials. These compounds exhibit phase transitions with exciting dielectric and elastic properties. In this aspect, glycine with orthophosphorus acid forms glycine phosphite (GPI) single crystals. Good quality, optical transparent glycine phosphite (GPI) single crystals are grown from aqueous solution. GPI crystals have a wide range of nonlinear optical applications. The present work focuses on the growth of GPI from its aqueous solution by slow evaporation method. The PXRD (powder XRD) pattern recorded at ambient temperature shows the single phase nature of the grown GPI crystals and it exists in the monoclinic system with space group P21/a. Etching studies were carried out to know more about the growth morphology and FTIR spectra shows the presence of a variety of normal mode vibration of GPI crystals. Dielectric studies were carried out from 100 K to 383 K. the ferroelectric to para electric transition was observed at 201 K. The dielectric relaxation of the grown crystals was studied using Debye fitting. The activation energy associated with the transition was also calculated. As the GPI crystals are paraelectric at room temperature, no second order non linearity was observed.
GROWTH, STRUCTURAL, THERMAL AND THZ GENERATION PROPERTIES OF MODIFIED DAST, CMST AND BMST CRYSTALS: A COMPARATIVE STUDY
(Springer, 2024-06) Shanmuga Sundari, S; Ganesh, D; Kanchana, P; Arnadevi, N; Chaudhary, A K; Prabha Devi, B
Growth of 4-N-N-dimethylamino-4-N -methyl-stilbazolium tosylate (DAST), 4-chloro-N-methyl 4-stilbazolium tosylate (CMST) and 4-bromo-N-methyl 4-stilbazolium tosylate (BMST) crystals by slope nucleation technique using mixed solvents are reported. Investigation on compositional, structural, thermal, luminescent and dielectric properties of these crystals were studied. Purity and the crystal quality are analysed using NMR and XRD. The thermal stability of the crystals is studied in detail from the TG-DTA. Emission characteristics are examined by photoluminescence spectra. Finally, 800 nm wavelength of 140 and 50 fs duration of pulses obtained from Ti:sapphire oscillator and amplifier were used for the measurement of refractive indices and absorption coefficients and generation of terahertz (THz) radiation. The conversion efficiency of DAST, CMST and BMST with respect to incident laser power of 150 mW were of the order of , and , respectively. Finally, the significance of effective polarisability in THz generation has been demonstrated in terms of rotational angle
INDUCED FERROMAGNETISM IN FE DOPED CEO2 NANOPARTICLES
(Elsevier, 2018) Shanmuga Sundari, S; Sugan, S; Pabitha, G
Ceria / CeO2 / Cerium nanoparticles are fluorite-structured rare earth oxide. Cerium oxide is an important material which finds applications as polishing agents, sunscreens, solid electrolytes, and automotive exhaust catalysts. Nano structured CeO2 is very attractive due to its improvements in the redox properties, transport properties and surface to volume ratio with respect to bulk materials. In the present work, CeO2 nanoparticles and Fe doped CeO2 (CeO2 + x mole% of Fe, where x= 1, 2, 3, 4 and 5) have been prepared by co-precipitation method. All the prepared samples were characterized for its structural, optical and magnetic properties by XRD, FTIR, SEM, UV-Vis and VSM analysis respectively. The absence of secondary peaks and cubic fluorite structures were confirmed by XRD and a complete solid solution was achieved between Fe and Ce in all the prepared samples. Uniform spherical like structures was observed from SEM micrographs. Scherrer’s formula was used to calculate the crystallite size and there is no much variation by the incorporation of Fe in CeO2 matrix. UV-Vis spectral analysis was carried out using DRS method and the absorption coefficient, direct band gap was calculated for all the prepared CeO2 nanoparticles. The pristine CeO2 is diamagnetic in nature. The doping of Fe in CeO2 induces ferromagnetism in CeO2 and the hysteresis area increases till 3 mol% of Fe and decreasing for further increase in concentration. Hence to induce a ferromagnetic property in CeO2 nanoparticles 3 mol% of Fe is optimum.
INFLUENCE OF CARBOXYLIC ACIDS ON STRUCTURAL, OPTICAL, THERMAL, AND ELECTRICAL PROPERTIES OF FERROELECTRIC GLYCINE PHOSPHITE SINGLE CRYSTALS
(Springer Link, 2022-06-28) Shanmuga Sundari, S; Arunadevi, N; Kanchana, P; Meena, P; Ranjith Kumar, E; Hosam O, Elansary; Eman A, Mahmoud; Shaimaa A. M, Abdelmohsen
Glycine phosphite (GPI), a semi-organic nonlinear optical NLO material, has been synthesized at room temperature. Slow evaporation method has been adopted to grow the single crystals of GPI and acetic acid, benzoic acid, formic acid, oxalic acid, and succinic acid-doped GPI crystals. The synthesized crystals are exposed to x-ray diffraction XRD, Fourier transform infrared (FTIR), and differential scanning calorimetry analysis DSC. The effects of doping on the structural parameters are analyzed. All the functional groups are identified by the corresponding peaks in the FTIR spectra. The UV–Vis spectrum shows that the materials have good optical transparency. The energy band gap values are found to be in the range of 5.1–5.4 eV for all the crystals. The mechanical stability of the grown crystals changes with different doping acids. The thermal studies were also affected by the addition of doping acids to the GPI crystal. Growth patterns and defect formation were studied by means of chemical etching. The dielectric constant and loss were evaluated from 300 to 410 K. It confirms that the dielectric constant value of GPI is higher than the acid-doped crystals.
INFLUENCE OF TRANSITION METAL IONS ON MULTIFERROIC PROPERTIES OF LEAD-FREE NBT–BT CERAMICS
(World Scientific Publishing Company, 2019-12-17) Shanmuga Sundari, S; Dhanasekaran, R
Using the conventional solid-state reaction method, 0.5wt.% of MnO2-, NiO-, Cr2O3-, Fe2O3- and Co2O3-added 0.94Na0.5 Bi0.5 TiO3 (NBT)–0.06BaTiO3 (BT) ceramics were prepared. The perovskite nature of the prepared ceramics was analyzed by powder XRD and the surface morphology was studied by means of SEM. The dielectric analysis was carried out from room temperature to 350∘ C at various frequencies and the diffusive transition at the dielectric maxima confirmed the relaxor nature of the ceramics. Creation of oxygen vacancies by the possible substitution of ferromagnetic impurities decreased the dielectric constant and piezoelectric constant (d33) The co-existence of ferromagnetism and the ferroelectricity was observed in the Mn, Ni, Co and Cr-added NBT–BT ceramics. The magnetic force microscopy (MFM) analysis was carried out to study the ferromagnetic domains in the prepared ceramic
OPTICAL AND BIOLOGICAL CHARACTERISTICS OF NOVEL ORGANIC SINGLE CRYSTAL 4-CHLORO N-METHYL 4-STILBAZOLIUM TOSYLATE
(Elsevier, 2019) Arunadevi, N; Kanchana, P; Mehala, M; Shanmuga Sundari, S
When compared with inorganic materials, the molecular organic materials acquire significant interest because of their considerable nonlinear optical properties, virtual unlimited design possibilities and extremely fast response times. Amongst them, organic crystals which are based on the charged chromophores and substantial Coulomb interaction have a number of benefits over non-ionic species, like first-order hyperpolarizability or greater molecular nonlinearity, durable stability and having a larger capability to override the dipole–dipole interactions and therefore it forms a non-centro symmetric macroscopic packing. For instance, DAST (4-N, N-dimethylamino-4′-N′-methyl-stilbazolium tosylate), the organic salt crystal, is one of the finest nonlinear optical materials having larger second-order nonlinear optical susceptibilities. Even though benchmark stilbazolium crystals display a great macroscopic nonlinearity and noble crystal characteristics, improving these physical properties comprising the environmental stability is a provocative topic. Based on this, the present paper discusses the growth of cationic substituted DAST namely 4-chloro -N-methyl 4-stilbazolium tosylate (CMST). Knoevenagel reaction method was used to synthesis CMST salt using Dean-Stark apparatus. The synthesized salt of CMST was dried at 100 °C for 24 h. The dried CMST salt was used to grow the crystals after three recrystallization process. Based on the solubility curve new solvent, mixture of methanol and acetonitrile was used to grow the crystals at room temperature by slope nucleation method. Structure of the grown crystals was characterized using single crystal XRD and FTIR. The compositional analysis was carried out using NMR and CHN analysis. Luminescence characteristics was studied using photoluminescence spectrum. The dielectric characteristics ware carried out from room temperature to 250 °C. Invitro analysis was carried out in the cancer cell line to study it’s anti-cancer activity.
STRUCTURAL AND OPTICAL PROPERTIES OF SALICYL-N-METHYL-4-STILBAZOLIUM TOSYLATE: THERMAL, DFT, MEP AND HIRSHFELD SURFACE ANALYSIS
(Elsevier, 2023-01-05) Shanmuga Sundari, S; Mehala, M; Arunadevi, N; Kanchana, P; Salman S, Alharthi; Ranjith Kumar, E; Al-Douri, Y; Abd El-Rehim, A F
The structural characteristics and optimized geometry of salicyl-N-methyl-4-stilbazolium tosylate (SMST), a derivative of the prominent electro-nonlinear optic crystal 4-(N,N-dimethylamino)-N-methyl-4-toluene sulfonate (DAST) is investigated. Its morphology, spectral, vibrational, thermal, and electronic features have been examined in studies like FT-IR, UV-Transmittance spectroscopy, single crystal XRD and TG-DTA analysis. Thermal parameters like activation energy, entropy, enthalpy, and Gibbs free energy suggest that the reaction is slower and non-spontaneous. The optical constants like energy band gap, absorption coefficient, extinction coefficient, refractive index, and skin depth of SMST have been calculated. The energy band gap value is found to be 2.69 eV, which makes SMST a potential and promising material for non-linear optical applications. The dielectric behavior of SMST is in agreement with the property needed for NLO materials. Theoretical calculations like density functional theory and frontier molecular orbitals- HOMO and LUMO are investigated to analyze the structural properties, atomic arrangement, oriented geometry, and dipole moment. Molecular electrostatic potential (MEP), Hirshfeld surface, and 2D fingerprint plot analysis are examined to provide information about the molecular interaction, crystal packing, electron density, and intermolecular properties of atomic contacts. Second Harmonic Generation of SMST shows greater efficiency than urea, which confirms that SMST crystal can leads to many applications in the optical field.
STRUCTURAL, CONDUCTIVITY AND DFT STUDIES OF L-HISTIDINIUM PHOSPHITE – FERROELECTRIC PHOSPHITE SINGLE CRYSTAL
(Elsevier, 2021-08) Shanmuga Sundari, S; Mano Priya, A; Durairajan, A; Valente, M A
L-Histidinium phosphite [C6N3O2H10]+. [HPO3H]- abbreviated as HPI, is a semi-organic nonlinear optical material. In the present work HPI crystals were grown from the aqueous solution of HPI by slow evaporation technique. Single crystal XRD (SXRD) reveals that the resulting crystals predominantly exhibit monoclinic structure with space group P21. Sharp and well-defined peaks of the powder XRD pattern attested the good crystallinity of HPI and the pattern is in agreement with SXRD results. The different modes of vibrations of molecular groups and functional groups present in the HPI crystal was investigated using IR spectra. It is evident from the UV–Vis spectrum that HPI is transparent in the examined frequency regime. The TG-DTA studies ascertain that the crystal is thermal stable till 230 °C. A.C. and D.C. conduction mechanism in the grown crystals were studied from 119 K to 380 K for 1 kHz to 1 MHz frequency range. The pattern suggests that there is ferroelectric to paraelectric transition at 270 K. This transition temperature is higher than the glycine phosphite crystals. Detailed insight about the conduction mechanism in HPI crystals was analyzed by complex impedance and modulus studies. Density functional theory was applied to know in detail about the structure and non-linear optical characteristics of the grown crystal and it attested that HPI is NLO active at room temperature.
STRUCTURAL, OPTICAL, THERMAL, BIOLOGICAL AND MOLECULAR DOCKING STUDIES OF GUANIDINE BASED NAPHTHOATE METAL COMPLEXES
(Elsevier, 2021-06) Arunadevi, N; Swathika, M; Prabha Devi, B; Kanchana, P; Shanmuga Sundari, S; Jone Kirubavathy, S; Subhapriya, P; Ranjith Kumar, E
The present work reports the complexation of few d-block metals with 3-hydroxy-2-naphthoic acid and guanidine which yields corresponding mononuclear complex bis(guaninium) 3-hydroxy-2-naphthoate metal (II) dihydrate of the type M(CN3H5)2{C10H6(3-O)(2-COO)}].2H2O, where M= form Mn(II), Fe(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Pb(II) and Ca(II) of ratio 1:2:4 – metal: acid: base. Characterization of the complexes were done by elemental analysis, IR spectra, UV-Visible spectroscopy, TG-DTA, powder XRD. TG-DTA study reveals various decomposition pattern and thermal stability of the metal complexes. Crystalline nature of the metal complexes is confirmed form powder XRD measurement. SEM coupled with EDAX and AFM confirms the presence of nano-sized metal oxides. Antibacterial studies of the metal complex prove that they are active against Bacillus subtilis and Escherichia coli. Furthermore, molecular docking was carried out for a study of physicochemical properties and to show the binding energy of ligands with proteins.