03891nas a2200337   4500008004100000022001400041245018200055210006900237260008400306300001400390490000600404520267800410653001203088653001003100653001003110653003803120653001403158653001703172100002503189700001903214700002603233700002003259700002003279700002103299700002003320700001803340700001703358700002403375700002603399856012803425       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  uhttp://library.ncl.res.in/content/rapid-efficient-synthesis-and-characterization-silver-gold-and-bimetallic-nanoparticles-002192nas a2200229   4500008004100000022001400041245012500055210006900180260000800249490000700257520138400264653001001648653003101658653000901689653001901698653003001717653000801747100002101755700002701776700002801803856013101831       2024                        eng d  a2468-023000aTuning the optical properties of Ln3+-doped-Y2O3@ZnO@Au core-shell heterostructures for visible-to-NIR photon harvesting0 aTuning the optical properties of Ln3dopedY2O3ZnOAu coreshell het  cJAN0 v443 a<p>
	Here, compact Yb3+-Er3+-Tm3+ doped Y2O3 phosphor microspheres were synthesized by solvothermal method which gave emission in the entire visible region under 980 nm excitation. The effect of doping alkali ions like lithium on the upconversion emission of YYET phosphors is investigated. An epitaxial layer of ZnO is grown around the YYETL (Li+ doped YYET) microspheres by hydrothermal technique. An analysis of the influence of the ZnO shell thickness on the upconversion emission of core microspheres is done. Initial growth of a thin layer of ZnO on the YYETL microspheres causes enhancement in upconversion emission due to passivation of surface defects of core microspheres. Quenching of anti-Stokes emission occurs for thicker ZnO shell coating. Further, it is decorated with AuNPs to study the effect of plasmonics on the optical property of the developed heterostructure. The overlap between the upconversion emission spectra of core microspheres and the LSPR peak of AuNPs modulates the property of the entire structure. The optimized samples were checked for photocatalytic application by degradation of Rh6G dye under solar irradiation. YYETL@ZnO@Au core-shell samples exhibited highest rate constant of 0.00395 min(-1), which is attributed to better exploitation of the UV-Vis-NIR region of the solar spectrum by all three components of the heterostructure.</p>
10aAuNPs10aCore-shell heterostructure10aLRET10aPhotocatalysis10aUpconversion microspheres10aZnO1 aJayswal, Shefali1 aLuwang, Meitram, Niraj1 aMoirangthem, Rakesh, S.  uhttp://library.ncl.res.in/content/tuning-optical-properties-ln3-doped-y2o3znoau-core-shell-heterostructures-visible-nir-photon