02718nas a2200229 4500008004100000022001400041245012700055210006900182260007100251300001600322490000700338520184800345100002002193700001902213700002202232700001502254700002002269700002502289700003002314700001502344856012902359 2005 eng d a0743-746300aCobalt and magnesium ferrite nanoparticles: preparation using liquid foams as templates and their magnetic characteristics0 aCobalt and magnesium ferrite nanoparticles preparation using liq a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcNOV a10638-106430 v213 a

An easy and convenient method for the synthesis of cobalt and magnesium ferrite nanoparticles is demonstrated using liquid foams as templates. The foam is formed from an aqueous mixture of an anionic surfactant and the desired metal ions, where the metal ions are electrostatically entrapped by the surfactant at the thin borders between the foam bubbles and their junctions. The hydrolysis is carried out using alkali resulting in the formation of desired nanoparticles, with the foam playing the role of a template. However, in the formation of ferrites with the formula MFe2O4, where the metal ion and iron possess oxidation states of +2 and +3, respectively, forming a foam from a 1:2 mixture of the desired ionic solutions would lead to a foam composition at variance with the original solution mixture because of greater electrostatic binding of ions possessing a greater charge with the surfactant. In our procedure, we circumvent this problem by preparing the foam from a 1:2 mixture of M2+ and Fe2+ ions and then utilizing the in situ conversion of Fe2+ to Fe3+ under basic conditions inside the foam matrix to get the desired composition of the metal ions with the required oxidation states. The fact that we could prepare both CoFe2O4 and MgFe2O4 particles shows the vast scope of this method for making even multicomponent oxides. The magnetic nanoparticles thus obtained exhibit a good crystalline nature and are characterized by superparamagnetic properties. The magnetic features observed for CoFe2O4 and MgFe2O4 nanoparticles are well in accordance with the expected behaviors, with CoFe2O4 particles showing higher blocking temperatures and larger coercivities. These features can easily be explained by the contribution of Co2+ sites to the magnetocrystalline anisotropy and the absence of the same from the Mg2+ ions.

1 aBala, Tanushree1 aSankar, C., R.1 aBaidakova, Marina1 aOsipov, V.1 aEnoki, Toshiaki1 aJoy, Pattayil, Alias1 aPrasad, Bhagavatula L. V.1 aSastry, M. uhttps://library.ncl.res.in/content/cobalt-and-magnesium-ferrite-nanoparticles-preparation-using-liquid-foams-templates-and-001417nas a2200169 4500008004100000245008600041210006900127260000800196300001400204490000600218520074400224653009300968100002101061700002001082700003001102856011501132 2007 eng d00aControlled aggregation of gold nanoparticle networks induced by alkali metal ions0 aControlled aggregation of gold nanoparticle networks induced by  cAUG a2683-26890 v73 a

Gold nanoparticle networks were obtained by linking them with cysteine modified triethyleneglycols. The oligo-ether linker molecule initially having a linear structure probably adopts a crown ether type structure upon complexation with alkali metal ions that leads to a controlled aggregation of the network. The extent of aggregation depends on the degree of conformational change in the molecule upon complexation with the metal ion, which in turn is governed by the metal ion radius leading to a dependence of red shift of the surface plasmon resonance on the metal ion radius. Since this network is present in the organic solvent they also act as phase transferring agent for the alkali metal ions from aqueous to organic media.

10aAggregation; Alkali Metal Ions; Au Nanoparticles; Crown Ether; Surface Plasmon Resonance1 aTamang, Sudarsan1 aHotha, Srinivas1 aPrasad, Bhagavatula L. V. uhttps://library.ncl.res.in/content/controlled-aggregation-gold-nanoparticle-networks-induced-alkali-metal-ions01220nas a2200169 4500008004100000022001400041245013000055210006900185260011000254300001400364490000700378520045800385100002100843700002900864700003000893856012700923 2008 eng d a0959-942800aCarbon nano horn and bovine serum albumin hierarchical composite: towards bio-friendly superhydrophobic protein film surfaces0 aCarbon nano horn and bovine serum albumin hierarchical composite aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcJUN a3422-34250 v183 a

Highly hydrophilic glass substrates when coated with films of carbon nano horns dispersed in the ubiquitous protein bovine serum albumin display hydrophobic characteristics. Incidentally both the materials used to create the final hydrophobic surface are known to be highly bio-compatible. The features observed are accredited to the replication of the micro and nanoscale hierarchical structures of carbon nano horns in the final film composite.

1 aJadhav, Anil, D.1 aOgale, Satishchandra, B.1 aPrasad, Bhagavatula L. V. uhttps://library.ncl.res.in/content/carbon-nano-horn-and-bovine-serum-albumin-hierarchical-composite-towards-bio-friendly-001401nas a2200253 4500008004100000022001400041245009700055210006900152260010600221300001400327490000700341520044000348653001700788653002100805653002300826653002100849653002500870100001900895700002900914700002600943700002300969700003000992856012501022 2008 eng d a0040-403900aC-glycosides of dodecanoic acid: new capping/reducing agents for glyconanoparticle synthesis0 aCglycosides of dodecanoic acid new cappingreducing agents for gl aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcOCT a6227-62300 v493 a

A concise synthesis of 12-C-glycosylated dodecanoic acids employing an olefin cross-metathesis reaction is developed. Examination of these acids as capping agents for the synthesis of metal nanoparticles reveals that they do not cap the Co-metal nanoparticles synthesized in aqueous phase, but that two of them can reduce and cap the Ag nanoparticles in water without any aggregation. (C) 2008 Elsevier Ltd. All rights reserved.

10aC-Glycosides10aCross metathesis10aglyconanoparticles10aGrubbs' catalyst10asilver nanoparticles1 aRamana, C., V.1 aDurugkar, Kulbhushan, A.1 aPuranik, Vedavati, G.1 aNarute, Sachin, B.1 aPrasad, Bhagavatula L. V. uhttps://library.ncl.res.in/content/c-glycosides-dodecanoic-acid-new-cappingreducing-agents-glyconanoparticle-synthesis-001628nas a2200217 4500008004100000022001400041245022500055210006900280260011000349300001200459490000700471520064800478100002301126700001501149700001601164700002301180700002201203700002301225700003001248856013201278 2009 eng d a0959-942800aComposites of plasma treated poly(etherimide) films with gold nanoparticles and lysine through layer by layer assembly: a ``friendly-rough'' surface for cell adhesion and proliferation for tissue engineering applications0 aComposites of plasma treated polyetherimide films with gold nano aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcDEC a544-5500 v193 a

A composite film fabricated by plasma treated poly(etherimide) with subsequent deposition of gold nanoparticles and lysine using layer by layer assembly has been demonstrated to be good for cell attachment and proliferation making it an attractive strategy for tissue engineering applications. As compared to the other methods the decrease in contact angle obtained here does not depend much on the plasma treatment thus affecting the polymer structure minimally. A combination of surface roughness provided by the gold nanoparticles and the presence of amine groups of lysine is hypothesized to be the reason for the features observed.

1 aD'Britto, Virginia1 aTiwari, S.1 aPurohit, V.1 aWadgaonkar, P., P.1 aBhoraskar, S., V.1 aBhonde, Ramesh, R.1 aPrasad, Bhagavatula L. V. uhttps://library.ncl.res.in/content/composites-plasma-treated-polyetherimide-films-gold-nanoparticles-and-lysine-through-layer-001974nas a2200241 4500008004100000022001400041245011600055210006900171260007300240300001000313490000800323520107600331653001501407653002701422653002201449653001101471653002301482100002301505700002501528700003001553700002301583856012601606 2010 eng d a0921-510700aCitrate-capped quantum dots of CdSe for the selective photometric detection of silver ions in aqueous solutions0 aCitratecapped quantum dots of CdSe for the selective photometric aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcAPR a60-650 v1683 a

A simple strategy for the synthesis of water soluble, luminescent, citrate-capped CdSe quantum dots (Q-CdSe) and their applications to selective detection of silver ions are described. The steady state photoluminescence (PL) spectra show single, narrow emission band at ca. 554 nm without any contribution from the trap states. The effect of various ions including physiologically important metal ions (viz. K(+), Ca(2+), Fe(3+), Zn(2+), Mg(2+), Mn(2+), Cu(2+), Ag(+), Pb(2+) and Cd(2+)), on the PL intensity of citrate-capped Q-CdSe has been studied. Among these, selective luminescence quenching with Ag(+) ion was found to be predominant. Under the optimum conditions, the response was linear between 1.7 and 18 mu M. The quenching constant K(SV) was found to be ca. 3.4 x 10(5) M(-1). The mechanism of photoluminescence quenching of Q-CdSe by metal ions (Ag(+)) is also discussed. Based on these studies, the potential use of Q-CdSe as a luminescent probe for the selective detection of silver ion has been proposed. (C) 2009 Elsevier B.V. All rights reserved.

10aAg(+) ions10aLuminescence quenching10aLuminescent probe10aQ-CdSe10aTri-sodium citrate1 aIngole, Pravin, P.1 aAbhyankar, Rajiv, M.1 aPrasad, Bhagavatula L. V.1 aHaram, Santosh, K. uhttps://library.ncl.res.in/content/citrate-capped-quantum-dots-cdse-selective-photometric-detection-silver-ions-aqueous-001623nas a2200193 4500008004100000022001400041245014900055210006900204260011000273300001400383490000700397520078300404100002301187700001901210700002001229700002201249700003001271856012801301 2010 eng d a1144-054600aClicking molecular hooks on silica nanoparticles to immobilize catalytically important metal complexes: the case of gold catalyst immobilization0 aClicking molecular hooks on silica nanoparticles to immobilize c aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcAUG a2662-26700 v343 a

Gold mediated reactions have emerged as one of the best choices for affecting a variety of chemical transformations with a wide range of functional group tolerance. Application of such transformations to industrial processes necessitates immobilization of the Au ions into a matrix for easy separation of the catalyst after reaction. We report the synthesis and characterization of silica nanoparticles in which Au(III) has been immobilized through a 1,2,3-triazole linkage using an alkynalated picolinic acid exploiting ``click chemistry''. The Au( III) immobilized silica nanoparticle has been thoroughly characterized using FT-IR, C-13 CP MAS NMR and XPS. The utility of these particles as an easily separable catalyst for the Hashmi phenol synthesis is also reported.

1 aGanai, Anal, Kumar1 aBhardwaj, Rima1 aHotha, Srinivas1 aGupta, Sayam, Sen1 aPrasad, Bhagavatula L. V. uhttps://library.ncl.res.in/content/clicking-molecular-hooks-silica-nanoparticles-immobilize-catalytically-important-metal-001868nas a2200205 4500008004100000022001400041245010300055210006900158260011000227300001200337490000700349520105000356100002301406700002001429700002101449700001901470700003001489700002101519856012201540 2010 eng d a1463-926200aContinuous flow synthesis of functionalized silver nanoparticles using bifunctional biosurfactants0 aContinuous flow synthesis of functionalized silver nanoparticles aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcAPR a609-6150 v123 a

Silver nanoparticles were synthesized by continuous flow methods using biosurfactants, namely, oleic acid sophorolipid (OASL) and stearic acid sophorolipid (SASL). Both the sophorolipids can act as reducing and capping agents. The effect of temperature on the completion of nanoparticle formation and the particle growth dynamics (size) were studied in batch mode. While the completion of the reaction using oleic acid sophorolipid needed 20 min, only 5 min were required with the stearic acid sophorolipid as capping and reducing agent. Hence all the continuous flow experiments were carried out using the stearic acid sophorolipid. The continuous flow synthesis of silver nanoparticles was carried out in a stainless steel helical coil and also in a spiral polymeric minichannel reactor. The DLS results show that higher flow rate leads to the formation of bigger and polydisperse particles because of incomplete reactions. Higher residence time allowed the completion of reaction leading to spherical, small and monodisperse particles.

1 aKumar, D., V. Ravi1 aKasture, Manasi1 aPrabhune, Asmita1 aRamana, C., V.1 aPrasad, Bhagavatula L. V.1 aKulkarni, A., A. uhttps://library.ncl.res.in/content/continuous-flow-synthesis-functionalized-silver-nanoparticles-using-bifunctional-001597nas a2200205 4500008004100000022001400041245010300055210006900158260011000227300001200337490000700349520078500356100001801141700002301159700002101182700001901203700001701222700003001239856012201269 2010 eng d a1144-054600aCytotoxic and genotoxic assessment of glycolipid-reduced and -capped gold and silver nanoparticles0 aCytotoxic and genotoxic assessment of glycolipidreduced and capp aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcNOV a294-3010 v343 a

A systematic cytotoxic and genotoxic evaluation of glycolipid-conjugated silver and gold nanoparticles is carried out. These glycolipid nanoparticle conjugates are obtained by exploiting the reductive capability of a class of glycolipids called sophorolipids that play the role of capping agent as well. Further, when tested for their cytotoxicity and genotoxicity on HepG2 cells, these nanoparticles are found to be cytocompatible up to 100 mu M metal concentrations. Of the two metallic systems investigated, gold nanoparticles are found to be more cytocompatible than the same concentrations of silver nanoparticles. Similarly, it is also demonstrated that at 100 mu M, silver nanoparticles cause more DNA damage compared to gold nanoparticles of similar concentrations.

1 aSingh, Sanjay1 aD'Britto, Virginia1 aPrabhune, Asmita1 aRamana, C., V.1 aDhawan, Alok1 aPrasad, Bhagavatula L. V. uhttps://library.ncl.res.in/content/cytotoxic-and-genotoxic-assessment-glycolipid-reduced-and-capped-gold-and-silver-001712nas a2200205 4500008004100000022001400041245016800055210006900223260011000292300001200402490000600414520082600420100001801246700002101264700002101285700002201306700001901328700003001347856012901377 2011 eng d a2040-336400aCytotoxicity of sophorolipid-gellan gum-gold nanoparticle conjugates and their doxorubicin loaded derivatives towards human glioma and human glioma stem cell lines0 aCytotoxicity of sophorolipidgellan gumgold nanoparticle conjugat aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcJAN a575-5800 v33 a

Biocompatible gold nanoparticles were synthesized by using a naturally occurring gum-Gellan Gum-as a capping and reducing agent. These were further conjugated with sophorolipids which again were accessed through a biochemical transformation of a fatty acid. The cellular uptake of sophorolipid-conjugated gellan gum reduced gold nanoparticles and their cytotoxicity on human glioma cell line LN-229 and human glioma stem cell line HNGC-2 were investigated. Quite surprisingly even the simple sophorolipid-conjugated gellan gum reduced/capped gold nanoparticles showed greater efficacy in killing the glioma cell lines and, gratifyingly, the glioma stem cell lines also. The cytotoxic effects became more prominent once the anti cancer drug doxorubicin hydrochloride was also conjugated to these gold nanoparticles.

1 aDhar, Sheetal1 aReddy, Maheswara1 aPrabhune, Asmita1 aPokharkar, Varsha1 aShiras, Anjali1 aPrasad, Bhagavatula L. V. uhttps://library.ncl.res.in/content/cytotoxicity-sophorolipid-gellan-gum-gold-nanoparticle-conjugates-and-their-doxorubicin-0