01568nas a2200229   4500008004100000022001400041245007900055210006900134260005700203300001200260490000700272520079800279653002501077653001801102653001301120653000901133100001701142700002101159700002401180700002101204856011301225       2013                        eng d  a0035-451100aRheology and microstructural studies of regenerated silk fibroin solutions0 aRheology and microstructural studies of regenerated silk fibroin  a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGERcNOV  a833-8400 v523 a<p>Regenerated silk fibroin solutions (RSF) are produced by dissolving degummed silk fibers in water. We have observed that RSF solutions at a concentration less than 15 % by weight exhibit an unusual gel-like response in conventional shear rheology measurements. At higher concentrations, the response is predominantly viscous (or liquid-like). We have probed this counterintuitive behavior of silk fibroin solutions by using microrheology, and interfacial rheometry. Scattering techniques were also used to understand the microstructure of RSF solutions as a function of the concentration. Our studies suggest that the gel-like response of the RSF solution may result from the formation of an interfacial film at the air-solution interface, which dominates the bulk rheological response.</p>10aInterfacial rheology10aMicrorheology10aRheology10aSilk1 aNisal, Anuya1 aKalelkar, Chirag1 aBellare, Jayesh, R.1 aLele, Ashish, K.  uhttps://library.ncl.res.in/content/rheology-and-microstructural-studies-regenerated-silk-fibroin-solutions-003892nas a2200337   4500008004100000022001400041245018200055210006900237260008400306300001400390490000600404520267800410653001203088653001003100653001003110653003803120653001403158653001703172100002503189700001903214700002603233700002003259700002003279700002103299700002003320700001803340700001703358700002403375700002603399856012903425       2014                        eng d  a1178-201300aRapid efficient synthesis and characterization of silver, gold, and bimetallic nanoparticles from the medicinal plant plumbago zeylanica and their application in biofilm control0 aRapid efficient synthesis and characterization of silver gold an  aPO BOX 300-008, ALBANY, AUCKLAND 0752, NEW ZEALANDbDOVE MEDICAL PRESS LTDcMAY  a2635-26530 v93 a<p>Background: Nanoparticles (NPs) have gained significance in medical fields due to their high surface-area-to-volume ratio. In this study, we synthesized NPs from a medicinally important plant - Plumbago zeylanica. Materials and methods: Aqueous root extract of P. zeylanica (PZRE) was analyzed for the presence of flavonoids, sugars, and organic acids using high-performance thin-layer chromatography (HPTLC), gas chromatography-time of flight-mass spectrometry (GC-TOF-MS), and biochemical methods. The silver NPs (AgNPs), gold NPs (AuNPs), and bimetallic NPs (AgAuNPs) were synthesized from root extract and characterized using ultraviolet-visible spectra, X-ray diffraction (XRD), energy-dispersive spectrometry (EDS), transmission electron microscopy (TEM), and dynamic light scattering (DLS). The effects of these NPs on Acinetobacter baumannii, Staphylococcus aureus, and Escherichia coli biofilms were studied using quantitative biofilm inhibition and disruption assays, as well as using fluorescence, scanning electron microscopy, and atomic force microscopy. Results: PZRE showed the presence of phenolics, such as plumbagin, and flavonoids, in addition to citric acid, sucrose, glucose, fructose, and starch, using HPTLC, GC-TOF-MS, and quantitative analysis. Bioreduction of silver nitrate (AgNO3) and chloroauric acid (HAuCl4) were confirmed at absorbances of 440 nm (AgNPs), 570 nm (AuNPs), and 540 nm (AgAuNPs), respectively. The maximum rate of synthesis at 50 degrees C was achieved with 5 mM AgNO3 within 4.5 hours for AgNPs; and with 0.7 mM HAuCl4 within 5 hours for AuNPs. The synthesis of AgAuNPs, which completed within 90 minutes with 0.7 mM AgNO3 and HAuCl4, was found to be the fastest. Fourier-transform infrared spectroscopy confirmed bioreduction, while EDS and XRD patterns confirmed purity and the crystalline nature of the NPs, respectively. TEM micrographs and DLS showed about 60 nm monodispersed Ag nanospheres, 20-30 nm Au nanospheres adhering to form Au nanotriangles, and about 90 nm hexagonal blunt-ended AgAuNPs. These NPs also showed antimicrobial and antibiofilm activity against E. coli, A. baumannii, S. aureus, and a mixed culture of A. baumannii and S. aureus. AgNPs inhibited biofilm in the range of 96%-99% and AgAuNPs from 93% to 98% in single-culture biofilms. AuNPs also showed biofilm inhibition, with the highest of 98% in S. aureus. AgNPs also showed good biofilm disruption, with the highest of 88% in A. baumannii. Conclusion: This is the first report on rapid and efficient synthesis of AgNPs, AuNPs and AgAuNPs from P. zeylanica and their effect on quantitative inhibition and disruption of bacterial biofilms.</p>10aAgAuNPs10aAgNPs10aAuNPs10abiofilm inhibition and disruption10aGC-TOF-MS10aP. zeylanica1 aSalunke, Gayatri, R.1 aGhosh, Sougata1 aKumar, R., J. Santosh1 aKhade, Samiksha1 aVashisth, Priya1 aKale, Trupti, S.1 aChopade, Snehal1 aPruthi, Vikas1 aKundu, Gopal1 aBellare, Jayesh, R.1 aChopade, Balu, Ananda  uhttps://library.ncl.res.in/content/rapid-efficient-synthesis-and-characterization-silver-gold-and-bimetallic-nanoparticles-0