01933nas a2200193   4500008004100000022001400041245010500055210006900160260007100229300001600300490000800316520117500324100001901499700002001518700002301538700003001561700002201591856012601613       2011                        eng d  a1932-744700aFunctionalization of SBA-15 mesoporous materials using ``thiol-ene click'' michael addition reaction0 aFunctionalization of SBA15 mesoporous materials using thiolene c  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcSEP  a17774-177810 v1153 a<p>Methacrylate-labeled SBA-15 has been successfully synthesized from calcined SBA-15 and commercially available 3-trichlorosilyl propylmethacrylate. This material undergoes efficient thiol-ene ``click reaction'' with a variety of both thiol and disulfide-containing substrates in aqueous and organic media. The products were thoroughly characterized by a variety of analytical techniques including multinuclear (C-13, Si-29) solid-state NMR, TG-DTA, and nitrogen adsorption desorption studies. Disulfide-containing substrates in which the TCEP-mediated reduction of the disulfide bond and its subsequent addition to the methacrylate group anchored in SBA-15 in one-pot were used to synthesize a silica-protein hybrid material composed of biotin-labeled SBA-15 and streptavidin. Electrochemically active material was synthesized from the reaction of ferrocene-containing thiol and the methacrylate-labeled SBA-15. The ease of synthesis for the methacrylate-labeled SBA-15 material together with its ability to undergo efficient chemoselective thiol-ene reaction would make it a very attractive platform for the development of covalently anchored enzymes and sensors.</p>1 aKumari, Sushma1 aMalvi, Bharmana1 aGanai, Anal, Kumar1 aPillai, Vijayamohanan, K.1 aGupta, Sayam, Sen  uhttps://library.ncl.res.in/content/functionalization-sba-15-mesoporous-materials-using-thiol-ene-click-michael-addition-001259nas a2200205   4500008004100000022001400041245011400055210006900169260011000238300001400348490000700362520041800369100002300787700001900810700002500829700002100854700002700875700002200902856012900924       2012                        eng d  a1359-734500aSynthesis of functional hybrid silica scaffolds with controllable hierarchical porosity by dynamic templating0 aSynthesis of functional hybrid silica scaffolds with controllabl  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcMAR  a5292-52940 v483 a<p>We report a facile one-pot synthesis of hierarchically porous scaffolds, with independent control over nanoparticle mesoporosity and scaffold macroporosity. Our technique combines the chemistry of mesoporous silica nanoparticles with the control afforded by dynamic templating of surfactant mesophases. These materials are readily functionalizable and allow controllable spatial variation in macroporosity.</p>1 aGanai, Anal, Kumar1 aKumari, Sushma1 aSharma, Kamendra, P.1 aPanda, Chakadola1 aKumaraswamy, Guruswamy1 aGupta, Sayam, Sen  uhttps://library.ncl.res.in/content/synthesis-functional-hybrid-silica-scaffolds-controllable-hierarchical-porosity-dynamic-002834nas a2200253   4500008004100000022001400041245007900055210006900134260007100203300001400274490000700288520198600295653001402281653002002295653001302315653000802328653002602336653001802362100001902380700001902399700002702418700002202445856011302467       2013                        eng d  a0897-475600aLarge centimeter-sized macroporous ferritin gels as versatile nanoreactors0 aLarge centimetersized macroporous ferritin gels as versatile nan  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcDEC  a4813-48190 v253 a<p>Organized assemblies of bionanoparticles such as ferritin provides templates that can be exploited for nanotechnological applications. Organization of ferritin into well-defined three-dimensional assemblies is challenging and has attracted considerable attention recently. We have synthesized, for the first time, large (centimeter-sized) self-standing macroporous scaffold monoliths from ferritin bionanoparticles, using dynamic templating of surfactant H-1 domains. These scaffolds comprise three-dimensionally connected strands of ferritin, organized as a porous gel with porosity similar to 55 mu m. The iron oxide inside the ferritin scaffold can be easily replaced with catalytically active monodisperse zerovalent transition metal nanoparticles using a very simple protocol. Since the ferritin is cross-linked in the scaffold, it is significantly robust with enhanced thermal stability and better tolerance toward several organic solvents in Comparison to the native ferritin bionanoparticle. In addition, the scaffold macropores facilitate substrate and reagent transport and hence the monoliths containing active Pd or iron oxide nanoparticles inside apo-ferritin bionanoparticles were used as a recyclable heterogeneous catalyst for the oxidation of 2,3,6-trimethyl phenol to 2,3,6-trimethyl-1,4-benzoquinone (precursor for Vitamin E synthesis) and for Suzuki-Miyaura cross-coupling reaction in both aqueous and organic solvents. The protein shell around the nanoparticles protects them from agglomeration, a phenomenon that otherwise plagues nanoparticles-based catalysis. The presence of macropores allow the ferritin scaffold to act as catalytic monolith for continuous flow reactions having rapid reaction rates, while offering a low pressure drop. Finally, the Pd@apo-ferritin scaffold was immobilized inside a steel cartridge and used for the continuous flow hydrogenation of alkenes to their corresponding alkanes for 15 cycles without any loss of activity.</p>10acatalysis10acontinuous flow10aferritin10agel10amacroporous materials10aSelf-assembly1 aKumari, Sushma1 aKulkarni, Amol1 aKumaraswamy, Guruswamy1 aGupta, Sayam, Sen  uhttps://library.ncl.res.in/content/large-centimeter-sized-macroporous-ferritin-gels-versatile-nanoreactors-003121nas a2200253   4500008004100000022001400041245011400055210006900169260007100238300001600309490000600325520221300331653002102544653001702565653000802582653002102590653002502611100001902636700002002655700002102675700002002696700002202716856012902738       2014                        eng d  a1944-824400aFe-TAML encapsulated inside mesoporous silica nanoparticles as peroxidase mimic: femtomolar protein detection0 aFeTAML encapsulated inside mesoporous silica nanoparticles as pe  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcAUG  a13866-138730 v63 a<p>Peroxidase, such as horseradish peroxidase (HRP), conjugated to antibodies are routinely used for the detection of proteins via an ELISA type assay in which a critical step is the catalytic signal amplification by the enzyme to generate a detectable signal. Synthesis of functional mimics of peroxidase enzyme that display catalytic activity which far exceeds the native enzyme is extremely important for the precise and accurate determination of very low quantities of proteins (fM and lower) that is necessary for early clinical diagnosis. Despite great advancements, analyzing proteins of very low abundance colorimetrically, a method that is most sought after since it requires no equipment for the analysis, still faces great challenges. Most reported HRP mimics that show catalytic activity greater than native enzyme (similar to 40-fold) are based on metal/metal-oxide nanoparticles such as Fe3O4. In this paper, we describe a second generation hybrid material developed by us in which approximately 25 000 alkyne tagged biuret modified Fetetraamido macrocyclic ligand (Fe-TAML), a very powerful small molecule synthetic HRP mimic, was covalently attached inside a 40 nm mesoporous silica nanopartide (MSN). Biuret-modified Fe-TAMLs represent one of the best small molecule functional mimics of the enzyme HRP with reaction rates in water close to the native enzyme and operational stability (pH, ionic strength) far exceeding the natural enzyme. The catalytic activity of this hybrid material is around 1000-fold higher than that of natural HRP and 100-fold higher than that of most metal/metal oxide nanoparticle based HRP mimics reported to date. We also show that using antibody conjugates of this hybrid material it is possible to detect and, most importantly, quantify femtomolar quantities of proteins colorimetrically in an ELISA type assay. This represents at least 10-fold higher sensitivity than other colorimetric protein assays that have been reported using metal/metal oxide nanoparticles as HRP mimic. Using a human IgG expressing cell line, we were able to demonstrate that the protein of interest human IgG could be detected from a mixture of interfering proteins in our assay.</p>10acolorimetrically10aimmuno assay10aMSN10aperoxidase mimic10asignal amplification1 aKumari, Sushma1 aDhar, Basab, B.1 aPanda, Chakadola1 aMeena, Abhishek1 aGupta, Sayam, Sen  uhttps://library.ncl.res.in/content/fe-taml-encapsulated-inside-mesoporous-silica-nanoparticles-peroxidase-mimic-femtomolar-001112nas a2200181   4500008004100000022001400041245011000055210006900165260011000234300001600344490000700360520034800367100001900715700002100734700002500755700002200780856012800802       2015                        eng d  a1359-734500aMolecular Fe-complex as a catalyst probe for in-gel visual detection of proteins via signal amplification0 aMolecular Fecomplex as a catalyst probe for ingel visual detecti  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcJUL  a15257-152600 v513 a<p>We report the use of a molecular peroxidase mimic biuret-Fe-TAML for chemoselective labeling of proteins and the subsequent visual detection (&lt;0.1 pmoles) of the conjugate in a polyacrylamide gel by catalytic signal amplification. Use of this probe in activity based protein profiling (ABPP) of serine proteases is also demonstrated.</p>1 aKumari, Sushma1 aPanda, Chakadola1 aMazumdar, Shyamalava1 aGupta, Sayam, Sen  uhttps://library.ncl.res.in/content/molecular-fe-complex-catalyst-probe-gel-visual-detection-proteins-signal-amplification-001796nas a2200217   4500008004100000022001400041245008100055210006900136260009000205300000900295490000600304520100700310100002401317700001801341700002501359700001901384700001801403700001901421700002001440856011801460       2015                        eng d  a2041-172300aSelf-templated chemically stable hollow spherical covalent organic framework0 aSelftemplated chemically stable hollow spherical covalent organi  aMACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLANDbNATURE PUBLISHING GROUPcAPR  a67860 v63 a<p>Covalent organic frameworks are a family of crystalline porous materials with promising applications. Although active research on the design and synthesis of covalent organic frameworks has been ongoing for almost a decade, the mechanisms of formation of covalent organic frameworks crystallites remain poorly understood. Here we report the synthesis of a hollow spherical covalent organic framework with mesoporous walls in a single-step template-free method. A detailed time-dependent study of hollow sphere formation reveals that an inside-out Ostwald ripening process is responsible for the hollow sphere formation. The synthesized covalent organic framework hollow spheres are highly porous (surface area similar to 1,500m(2) g(-1)), crystalline and chemically stable, due to the presence of strong intramolecular hydrogen bonding. These mesoporous hollow sphere covalent organic frameworks are used for a trypsin immobilization study, which shows an uptake of 15.5 mu mol g(-1) of trypsin.</p>1 aKandambeth, Sharath1 aVenkatesh, V.1 aShinde, Digambar, B.1 aKumari, Sushma1 aHalder, Arjun1 aVerma, Sandeep1 aBanerjee, Rahul  uhttps://library.ncl.res.in/content/self-templated-chemically-stable-hollow-spherical-covalent-organic-framework-101627nas a2200169   4500008004100000245008800041210006900129260000800198300001200206490000700218520102900225100001901254700002001273700002201293700002201315856012001337       2017                        eng d00aCatalytic macroporous biohydrogels made of ferritin-encapsulated gold nanoparticles0 aCatalytic macroporous biohydrogels made of ferritinencapsulated   cFEB  a225-2320 v823 aReported is a modular approach for the incorporation and stabilization of gold nanoparticles inside a three-dimensional macroporous hydrogel made of ferritin. The strategy, which involves the dynamic templating of surfactant H-1 domains, demineralization, and remineralization helps to overcome aggregation and degradation issues usually associated with bare-metal-based nanocatalysts. The catalytic activity of the so-synthesized bionanocomposite hydrogel was demonstrated in both nitroaldol (Henry) and nitroreduction model reactions in aqueous solution at room temperature. An interesting synergistic effect between basic residues of the protein and the gold nanoparticles was found in the nitroaldol reaction when carried out in water in the presence of a phase-transfer catalyst. Furthermore, the reduction of 4-nitrophenol and 4-nitroaniline catalyzed by the nanocomposite scaffold in the presence of NaBH4 proceeded significantly faster than that using other known Au- and Ag-based catalysts under similar conditions.1 aKumari, Sushma1 aHaring, Marleen1 aGupta, Sayam, Sen1 aDiaz, David, Diaz  uhttps://library.ncl.res.in/content/catalytic-macroporous-biohydrogels-made-ferritin-encapsulated-gold-nanoparticles