02651nas a2200241 4500008004100000022001400041245011100055210006900166260007100235300001400306490000800320520176800328100002202096700001802118700002502136700002002161700002402181700002402205700002602229700001802255700001702273856011902290 2015 eng d a1089-563900aTerahertz spectroscopy and solid-state density functional theory calculations of cyanobenzaldehyde isomers0 aTerahertz spectroscopy and solidstate density functional theory  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJUL a7991-79990 v1193 a

Spectral signatures in the terahertz (THz) frequency region are mainly due to bulk vibrations of the molecules. These resonances are highly sensitive to the relative position of atoms in a molecule as well as the crystal packing arrangement. To understand the variation of THz resonances, THz spectra (2-10 THz) of three structural isomers: 2-, 3-, and 4-cyanobenzaldehyde have been studied. THz spectra obtained from Fourier transform infrared (FTIR) spectrometry of these isomers show that the resonances are distinctly different especially below 5 THz. For understanding the intermolecular interactions due to hydrogen bonds, four molecule cluster simulations of each of the isomers have been carried out using the B3LYP density functional with the 6-31G(d,p) basis set in Gaussian09 software and the compliance constants are obtained. However, to understand the exact reason behind the observed resonances, simulation of each isomer considering the full crystal structure is essential. The crystal structure of each isomer has been determined using X-ray diffraction (XRD) analysis for carrying out crystal structure simulations. Density functional theory (DFT) simulations using CRYSTAL14 software, utilizing the hybrid density functional B3LYP, have been carried out to understand the vibrational modes. The bond lengths and bond angles from the optimized structures are compared with the XRD results in terms of root-mean-square-deviation (RMSD) values. Very low RMSD values confirm the overall accuracy of the results. The simulations are able to predict most of the spectral features exhibited by the isomers. The results show that low frequency modes (<3 THz) are mediated through hydrogen bonds and are dominated by intermolecular vibrations.

1 aDash, Jyotirmayee1 aRay, Shaurnik1 aNallappan, Kathirvel1 aKaware, Vaibhav1 aBasutkar, Nitin, B.1 aGonnade, Rajesh, G.1 aAmbade, Ashootosh, V.1 aJoshi, Kavita1 aPesala, Bala uhttps://library.ncl.res.in/content/terahertz-spectroscopy-and-solid-state-density-functional-theory-calculations-001033nas a2200157 4500008004100000245011300041210006900154260000800223300001600231490000700247520042000254100002400674700002400698700002600722856012700748 2015 eng d00aVisible light-triggered disruption of micelles of an amphiphilic block copolymer with BODIPY at the junction0 aVisible lighttriggered disruption of micelles of an amphiphilic  cOCT a17708-177110 v513 a

A visible light-cleavable polymer is synthesised to overcome the limitations of UV-sensitive polymers. Photocleavable BODIPY functionalized with an ATRP initiator and alkyne was used to obtain an amphiphilic block copolymer by conducting the click reaction and polymerization simultaneously. Micellar assembly of the polymer was disintegrated under visible light irradiation with controlled release of cargo.

1 aPatil, Naganath, G.1 aBasutkar, Nitin, B.1 aAmbade, Ashootosh, V. uhttps://library.ncl.res.in/content/visible-light-triggered-disruption-micelles-amphiphilic-block-copolymer-bodipy-junction02081nas a2200169 4500008004100000022001400041245017800055210006900233260011000302300001600412490000600428520128300434100002001717700002401737700002601761856012401787 2016 eng d a2046-206900aPhotoresponsive assemblies of linear-dendritic copolymers containing azobenzene in the dendron interior: the effect of the dendron structure on dye encapsulation and release0 aPhotoresponsive assemblies of lineardendritic copolymers contain aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcAPR a43163-431700 v63 a

Hydrophobic dendrons with different numbers and positions of azobenzenes as well as different groups benzyl and dodecyl, on the periphery were synthesised and attached to poly(ethylene glycol) using copper-catalysed azide-alkyne cycloaddition to obtain linear-dendritic copolymers. Self-assembly of the polymers in aqueous solution was characterised using dynamic light scattering (DLS), transmission electron microscopy (TEM) and critical micelle concentration (cmc). Formation of H-aggregates during micellisation was shown for polymers with a higher number of azobenzene units. Photoisomerisation of azobenzene in the assemblies was studied and the rate constant of thermal photoisomerisation was calculated. Release of hydrophobic dye Nile red upon photoisomerisation of azobenzene occurred without disruption of micellar aggregates. Dye release varied with the pathway - thermal or visible light irradiation, followed for cis-trans isomerisation. The encapsulation capacity of the micelles and extent of dye release in either pathway were found to be influenced by the dendron structure. A polymer with a lower number of azobenzenes and aliphatic periphery on the dendron showed significantly different behaviour than polymers with a larger number of aromatic units.

1 aKalva, Nagendra1 aBasutkar, Nitin, B.1 aAmbade, Ashootosh, V. uhttps://library.ncl.res.in/content/photoresponsive-assemblies-linear-dendritic-copolymers-containing-azobenzene-dendron01701nas a2200157 4500008004100000245012600041210006900167260000800236300001400244490000700258520107200265100002401337700002401361700002601385856013201411 2017 eng d00aCopper and silver nanoparticles stabilized by bistriazole-based dendritic amphiphile micelles for 4-nitrophenol reduction0 aCopper and silver nanoparticles stabilized by bistriazolebased d cJUN a4546-45540 v413 aCopper and silver nanoparticles were fabricated in aqueous solution using micellar assemblies of dendritic amphiphiles containing triazole rings. Dendritic amphiphiles displaying a bistriazole unit between a hydrophobic benzyl ether dendron and two oligo(ethylene glycol) (OEG) chains were synthesized using click chemistry. Micelles were characterized by DLS, TEM, CMC determination, and dye encapsulation. Micellar size was dependent on the dendron backbone structure and OEG chain length. Metal nanoparticles were characterized by TEM and UV-Vis spectroscopy. The Cu NPs had a smaller average particle diameter than the Ag NPs. The micelle-stabilized nanoparticles, at a concentration of 7.5 ppm, were shown to efficiently catalyze the reduction of 4-nitrophenol to 4-aminophenol in the presence of NaBH4 in aqueous solution without stirring, using up to 1 ppm of substrate. The reaction catalyzed by Cu NPs followed zero order kinetics (k = 3.48 x 10(-3) M s(-1)), while the Ag NP-catalyzed reaction followed pseudo-first order kinetics (k = 1.28 x 10(-3) s(-1)).1 aPatil, Naganath, G.1 aBasutkar, Nitin, B.1 aAmbade, Ashootosh, V. uhttps://library.ncl.res.in/content/copper-and-silver-nanoparticles-stabilized-bistriazole-based-dendritic-amphiphile-micelles-401982nas a2200241 4500008004100000022001400041245013900055210006900194260000900263300001200272490000700284520113000291653001101421653001901432653001301451653001801464653002901482100002401511700002901535700002101564700002601585856012901611 2024 eng d a1060-132500aVisible light and pH-responsive star copolymer and doxorubicin-polymer conjugate micelles for combination drug delivery and bioimaging0 aVisible light and pHresponsive star copolymer and doxorubicinpol cFEB  a105-1160 v613 a

Amphiphilic 3-arm star copolymer containing visible light-cleavable BODIPY group and pH-responsive imine bonds at the junction of hydrophilic poly(ethylene glycol) (PEG) and two poly(epsilon-caprolactone) (PCL) arms was synthesized by the combination of ring-opening polymerization (ROP) and click chemistry. The formation and stimuli-responsive disruption of micelles were analyzed using dynamic light scattering and transmission electron microscopy. Dual stimuli-responsive release of anticancer drugs Doxorubicin (Dox) and Camptothecin (CPT) from the micelles was studied. Micellar assemblies containing Dox conjugated to PEG-BODIPY through imine bonds were prepared and controlled release of Dox in response to visible light and pH was shown. CPT and Dox-loaded star copolymer micelles as well as CPT loaded Dox-conjugated micelles were used in cellular uptake studies on MDA-MB 231 cells, and the synergistic effect of the two stimuli on the release of the two drugs was demonstrated inside the cells. Micellar assemblies also showed excellent bioimaging properties in the cellular uptake studies. [GRAPHICS]

10aBODIPY10adrug conjugate10amicelles10apH-responsive10avisible light-responsive1 aBasutkar, Nitin, B.1 aSurapaneni, Sai, Geetika1 aAlam, Md., Shafi1 aAmbade, Ashootosh, V. uhttps://library.ncl.res.in/content/visible-light-and-ph-responsive-star-copolymer-and-doxorubicin-polymer-conjugate-micelles