Development of Gelatin Based Inorganic Nanocomposite Hydrogels for Inactivation of Bacteria

In this investigation, silver nanocomposite hydrogels were developed by using acrylamide and biodegradable gelatin. Silver nanoparticles were generated throughout the hydrogel networks using in situ method by incorporating Ag⁺ ions and the subsequent treatment with sodium borohydride. The effect of gelatin on the swelling studies was investigated. The hydrogel synthesized silver nanocomposites were characterized by using Fourier transform infrared, UV–Visible spectroscopy, X-ray diffraction, thermogravimetric analysis, scanning electron and transmission electron microscopy techniques. The biodegradable gelatin-based silver nanocomposite hydrogels were tested for antibacterial properties. The results indicate that these biodegradable silver nanocomposite hydrogels can be useful in medical applications, as antibacterial agents.     

Spin polarization and Gilbert damping of Co2Fe(GaxGe1−x) Heusler alloys

The spin polarization (P) of ferromagnetic Heusler alloys, Co₂Fe(Ga_xGe_1?x) (x = 0, 0.25, 0.5, 0.75, and 1), is investigated by point contact Andreev reflection (PCAR) measurements. While the P values of the ternary Co₂FeGe and Co₂FeGa alloys are 0.58 and 0.59, respectively, the corresponding value for Co₂Fe(Ge_0.5Ga_0.25) is as high as 0.69. Co₂Fe(Ge_0.5Ga_0.5) alloy shows a strong tendency for L2₁ ordering and a high Curie temperature of 807 °C. Ab initio calculations indicate that the band structures of the Co₂FeGe and Co₂Fe(Ge_0.5Ga_0.5) alloys with L2₁ or B2 structures are half-metallic. Thin films of the quaternary Co₂Fe(Ge_0.5Ga_0.5) alloy grown on MgO(0 0 1) substrates order to the L2₁ structure upon annealing at 500 °C, giving rise to a high P of 0.75. This is the highest P value reported for Heusler alloy thin films using the PCAR technique. Ferromagnetic resonance measurements show that the Gilbert damping constant of the film is ～0.008. All these indicate that the Co₂Fe(Ge_0.5Ga_0.5) alloy is promising as a spin polarized current source for spintronics devices.     

Development of Sodium Carboxymethyl Cellulose-based Poly(acrylamide-co-2acrylamido-2-methyl-1-propane sulfonic acid) Hydrogels for In Vitro Drug Release Studies of Ranitidine Hydrochloride an Anti-ulcer Drug

The formation of sodium carboxymethyl cellulose (SCMC) based semi-interpenetrating networks (semi-IPN) with poly(acylamide-co-2-acrylamido-2-methy-l-propanesulfonic-acid) hydrogels. The hydrogels were prepared by free-radical polymerization using redox initiator. The characterizations of hydrogels were done by swelling experiments, FTIR spectroscopy and DSC analysis. Morphology of the samples were examined by SEM. Experimental results indicate that the semi-IPN hydrogel containing 0.10 g of SCMC and 5.829 mM of AMPS, shows the highest swelling capacity (64.83 g/g). The swelling behavior of the semi-IPN hydrogel (AS5) was studied in different pH solutions. The ranitidine hydrochloride drug loading and release of the semi-IPN hydrogels were studied by using a UV spectrophotometer.     

Development and Characterization of Curcumin Loaded Silver Nanoparticle Hydrogels for Antibacterial and Drug Delivery Applications

The present work involves the development of curcumin loaded silver hydrogel nanocomposites based on acrylamide and 2-acrylamido-2-methyl propanesulfonic acid, as a template by redox co-polymerization in the presence of hydrophilic crosslinker N,N ¹-methylenebisacrylamide. Silver nitrate was taken as the metal precursor and sodium borohydride as a reducing agent. The formation of silver nanoparticles was monitored using UV–Vis absorption spectroscopy. The developed hydrogel silver nanocomposites (HSNC) were characterized by FTIR, UV–Vis, thermogravimetric analysis, scanning electron microscopy and transmission electron microscopy. The curcumin loading and release characteristics were performed for different hydrogel systems. The developed HSNCs were evaluated for preliminary antibacterial applications.     

Development of microbial protective Kolliphor‐based nanocomposite hydrogels

In this scientific work, a novel class of antimicrobial nanocomposite hydrogels were designed and synthesized by chemical and environmentally bioprocess using Kolliphor, acrylamide, and mint leafs in order to achieve antiseptic property for wound applications. In the bioprocess approach, silver nitrate and gold chloride were nucleated with mint leafs in order to obtain effective free individual nano‐inorganic compounds to provide superior antibacterial assets. The formations of dual inorganic nanoparticles were confirmed by transmission electron microscopy, which indicated the size of nanoparticles in the range of approximately 3 ± 2 nm and without agglomeration. The formations of biomaterials were characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopic–energy dispersive spectrometric studies and their swelling properties were determined. Furthermore, the pure hydrogel and the dual inorganic nanocomposite hydrogels developed were tested for antibacterial activities. When compared with the neat hydrogel, the nanocomposite hydrogels significantly improved their anti‐bacterial activities on Bacillus bacterium. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42781.     

Effect of oxygen mixing percentage on structural,optical and electrical properties of ZnTiO3 thin films grown by RF magnetron sputtering

Journal of Materials Science: Materials in Electronics - Perovskites are important composites in the area of multidisciplinary applications. The enhancement in properties of the composite can be...     

Dielectric and piezoelectric studies of La doped PZT polymer composites

Lanthanum doped Lead Zirconate Titanate (La:Zr:Ti = 4:51:49) has been shaped to porous three dimensional structures through BURPS (Burntout Plastic spheres) process. The materials are then framed to low-density, low-permittivity 3-3 composites with silicone rubber as the second phase. Poled composite ceramics have shown significant increase in piezo-electric voltage coefficients (g₃₃3) with a corresponding drop in dielectric permittivity. Volume fraction of PZT poled is estimated using a theoretical model where the PZT is assumed to be made up of small cubelets of 1 to 2 micrometers in size.     

Magnetic hysteresis and crystallization studies on metallic glass alloy Fe67Co18B14Si1

Magnetic hysteresis studies were carried out on Metglas 2605 Co(Fe₆₇Co₁₈B₁₄Si₁) samples, cut parallel and perpendicular to the ribbon axis and annealed at different temperatures. The samples annealed at 450°C for 2 hr show a coercive force of 8·75 Oe and 0·60 Oe in the parallel and perpendicular directions respectively. Electron probe micro analysis studies revealed the onset of primary crystallization at 400°C and a gradual displacement of B and Si from the lattice as the annealing temperature was increased to 450°C. The observed large coercive force is due to an increase in anisotropy resulting from an intergrowth pattern of the type Fe _x Co_{1 −x} , 0·3<x<1·0, including boron containing phases such as (FeCo)B, (FeCo)₂B, (FeCo)₃B, developed by the displacement of and Si from the original amorphous lattice.