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Here, on ITO//Au patterned substrates SAMs of ferrocene (Fc) on the Au regions and of anthraquinone (AQ) on the ITO areas are prepared, exhibiting three stable redox states. Furthermore, by selectively oxidizing or reducing the Fc or AQ units, respectively, the surface properties are locally modified. As a proof-of-concept, such a confinement of the properties is exploited to locally form host–guest complexes with b-cyclodextrin on specific surface regions depending on the applied voltage., This work was funded by ERC StG 2012-306826 e-GAMES, ITN iSwitch 642196, Networking Research Center on Bioengineering, Biomaterials, and Nanomedicine (CIBER-BBN), the Generalitat de Catalunya (2017-SGR-918) and the Spanish Ministry of Economy and Competitiveness, through the FANCY CTQ2016-80030-R project and the ‘‘Severo Ochoa’’ Programme for Centers of Excellence in R&D (SEV-2015-0496). M. S. M. is enrolled in the Materials Science PhD Program of UAB. E. C. F. and B. J. R. are grateful for support by the Deutsche Forschungsgemeinschaft (SFB 858).

A highly appealing strategy to modulate a catalyst's activity and/or selectivity in a dynamic and noninvasive way is to incorporate a photoresponsive unit into a catalytically competent molecule. However, the description of the photoinduced conformational or structural changes that alter the catalyst's intrinsic reactivity is often reduced to a handful of intuitive static representations, which can struggle to capture the complexity of flexible organocatalysts. Here, we show how a comprehensive exploration of the free energy landscape of N-alkylated azobenzene-tethered piperidine catalysts is essential to unravel the conformational characteristics of each configurational state and explain the experimentally observed reactivity trends. Mapping the catalysts' conformational space highlights the existence of false ON or OFF states that lower their switching ability. Our findings expose the challenges associated with the realization of a reversible steric shielding for the photocontrol of Brønsted basicity of piperidine photoswitchable organocatalysts.

WOS: 000262560800010 beta-Cyclodextrin (beta-CD) is a cage-like molecule consisting of seven glucose units and have appropriate size to form inclusion complexes with many hormones, vitamins and drugs. Due to having very poor aqueous solubility, beta-cyclodextrin is modified chemically for various applications. Experiments were conducted to examine effects of pre-hemolytic concentration of beta-cyclodextrin and its modified derivatives, methyl-beta-cyclodextrin (M beta-CD) and dimethyl-beta-cyclodextrin (DM beta-CD), on the osmotic fragility of dog and goat erythrocytes. Blood samples collected from healthy 10 dogs and 10 goats were analyzed within 5 h of collection. Erythrocyte suspensions were mixed with various concentrations of beta-CD, M beta-CD and DM beta-CD. The mixtures were then incubated for 30 min at 37 degrees C and osmotic fragility of erythrocytes was measured. Incubation of all 3 Cyclo Dextrins (CDs) with erythrocyte suspensions of both species, dog and goat, induced a dose dependent increase in the erythrocyte osmotic fragility (pM beta-CD>beta-CD. Hemolytic doses of these CDs were lower for goat erythrocytes than those of the dog erythrocytes. When beta-CD and its methylated derivatives are even used in pre-hemolytic concentrations, they might also reduce life span of erythrocytes. Due to importance of scientific knowledge on the cellular activity of cyclodextrins and growing number of its potential applications on diagnosis food preparations, our results may help to deal with the hemolytic activity of CDs for in vivo studies.

Four- to 10-fold improvement of colour uniformity and minor changes of colour yield have been found upon dyeing Nylon 66 and microfiber Nylon 6 fabrics in the presence of cyclodextrin compared to dyeing without it. 1 H NMR data supported the role of cyclodextrin as dye complexing agent. Product quality, however, was also dependent on fabric nature, since for conventional Nylon 6, color uniformity was not improved by the presence of cyclodextrin systems.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:21:12Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:29:26Z : No. of bitstreams: 1 2-s2.0-19944363225.pdf: 461801 bytes, checksum: b3a3ff472d81282a625825bbbe66a790 (MD5) Made available in DSpace on 2014-05-27T11:21:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-12-01 GCTase production by a new strain of Bacillus alkalophillc CGII isolated from Brazilian wastewater of manioc flour industry was examined. The growth medium used was composed by 1.5% starch, 1.5% nitrogen and 1% Na 2CO3. Higher activity was obtained with starch, maltodextrin and galactose. When glucose was added to the medium, no enzyme production was observed. High enzyme activity and growth were reached when aeration was increased (88.6 U/mL). The enzyme characterization showed an optimum pH and temperature 8.0 and 55°C for starch hydrolyses, respectively. Mg+ and Ca++ showed small activation; however, Hg + and Cu+ showed a strong enzyme inhibition. Departamento de Bioquímica e Tecnologia Universidade Estadual Paulista Júlio Mesquita Filho, Araraquara, SP Departamento de Alimentos e Nutrição Faculdade De/FCF Universidade Estadual Paulista Júlio Mesquita Filho, Araraquara, SP Departamento de Bioquímica e Microbiologia Instituto de Biociências Universidade Estadual Paulista Júlio Mesquita Filho, Rio Claro, SP Instituto de Biociências de Rio Claro UNESP, Caixa Postal 199, 13506-900, Rio Claro, SP Departamento de Bioquímica e Tecnologia Universidade Estadual Paulista Júlio Mesquita Filho, Araraquara, SP Departamento de Alimentos e Nutrição Faculdade De/FCF Universidade Estadual Paulista Júlio Mesquita Filho, Araraquara, SP Departamento de Bioquímica e Microbiologia Instituto de Biociências Universidade Estadual Paulista Júlio Mesquita Filho, Rio Claro, SP Instituto de Biociências de Rio Claro UNESP, Caixa Postal 199, 13506-900, Rio Claro, SP

The separation of three pairs of enantiomeric herbicides has been successfully achieved by capillary electrophoresis at two different pH values in the presence of cyclodextrin derivatives previously synthesized in our laboratory. Two of these derivatives constitute a new class of receptor, the hemispherodextrins, in which a trehalose capping moiety is bonded to beta-cyclodextrin. Because of their peculiar structure hemispherodextrins have very promising characteristics and the low receptor concentration required to achieve separation deserves particular interest.

Oxidized (ONC) and hydrolyzed (HNC) nanocelluloses were prepared from high-grade pure cotton fibers (CFT), too short to be spun. They maintained the CFT crystallinity (IC=0.59). ONC and HNC were fully O-allylated affording ONC-ALL and HNC-ALL, respectively. ONC-ALL and HNC-ALL became completely amorphous. Bacterial nanocellulose (BNC) and ONC were graphted with glycidyl methacrylate (GMA) affording BNC-GMA and ONC-GMA, respectively. Substitution degree (DS=GMA residue versus glucose unit) range in BNC-GMA and ONC-GMA is 0.4-0.6. As GMA grafting forms a new C-C bond between cellulose and GMA and keeps OH cellulose groups unchanged, GMA nanocellulose maintains the cristallinity of the starting nanocellulose. The non polar allyl and GMA appendages decrease the hydrophilicity of cellulose. ONC-ALL and HNC-ALL were further functionalized by mono 6-[(mercaptotetramethylene) thiol]-_-cyclodextrin (CySH). GMA epoxide group was opened by water and by _-cyclodextrin (Cy) affording BNC-GMA-OH and BNC-GMA-Cy. GMA and allyl appendages induce nanocellulose capability to adsorb 2-naphthol (2N) and amoxicillin (A).