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ABSTRACT: Bovine serum albumin (BSA) protein adsorption on thin spun films of different metal octakishexylthiophthalocyanine [(C<sub>6</sub>S)<sub>8</sub>PcM, M=Cu, Ni] derivatives is investigated by using three independent spectroscopic measurements namely Raman spectroscopy, ellipsometry and surface plasmon resonance imaging. Thermally induced molecular self-reorganisations in the phthalocyanine films are found to have produced the changes in the surface energy which, in turn, control protein adsorption. The amount of BSA adsorption on [(C<sub>6</sub>S)<sub>8</sub>PcNi] is more limited than that on [(C<sub>6</sub>S)<sub>8</sub>PcCu] and this observation is consistent with the results on the surface wettability obtained from the contact angle measurements. The shift from the plasmonic resonance wavelength because of the BSA adsorption was significantly larger for the heat-treated [(C<sub>6</sub>S)<sub>8</sub>PcCu] than as-deposited film. Similar measurements on the [(C<sub>6</sub>S)<sub>8</sub>PcNi] films showed a limited BSA adsorption. The results of surface plasmon resonance experiments are consistent with those obtained from Raman spectroscopic and ellipsometric techniques.
IET Nanobiotechnology 04/2010; · 1.83 Impact Factor
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ABSTRACT: Bovine serum albumin (BSA) protein adsorption on thin spun films of different metal octakishexylthiophthalocyanine [(C(6)S)(8)PcM, M=Cu, Ni] derivatives is investigated by using three independent spectroscopic measurements namely Raman spectroscopy, ellipsometry and surface plasmon resonance imaging. Thermally induced molecular self-reorganisations in the phthalocyanine films are found to have produced the changes in the surface energy which, in turn, control protein adsorption. The amount of BSA adsorption on [(C(6)S)(8)PcNi] is more limited than that on [(C(6)S)(8)PcCu] and this observation is consistent with the results on the surface wettability obtained from the contact angle measurements. The shift from the plasmonic resonance wavelength because of the BSA adsorption was significantly larger for the heat-treated [(C(6)S)(8)PcCu] than as-deposited film. Similar measurements on the [(C(6)S)(8)PcNi] films showed a limited BSA adsorption. The results of surface plasmon resonance experiments are consistent with those obtained from Raman spectroscopic and ellipsometric techniques.
IET Nanobiotechnology 03/2010; 4(1):1-9. · 1.83 Impact Factor
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ABSTRACT: Surface plasmon resonance imaging (SPRI) is a useful tool for the study of surface biomolecular interactions allowing for label-free detection and elegant instrumentation. SPRI imaging system is described in this review with an emphasis on recent applications with examples of different biological interactions and high throughput analysis. Signal amplification in SPRI using nanoparticle and waveguide-based optical coupling is introduced. Finally the detection sensitivity of the SPRI system is examined in terms of other competitive methods.
IET Nanobiotechnology 10/2009; 3(3):71-80. · 1.83 Impact Factor
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ABSTRACT: Surface plasmon resonance imaging (SPRI) is a useful tool for the study of surface biomolecular interactions allowing for label-free detection and elegant instrumentation. SPRI imaging system is described in this review with an emphasis on recent applications with examples of different biological interactions and high throughput analysis. Signal amplification in SPRI using nanoparticle and waveguide-based optical coupling is introduced. Finally the detection sensitivity of the SPRI system is examined in terms of other competitive methods.
IET Nanobiotechnology 10/2009; · 1.83 Impact Factor
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ABSTRACT: Electrochromic properties of spun films of bis[octakis(hexylthio)phthalocyaninato] dysprosium(III) were investigated for determining nicotinamide adenine dinucleotide hydride (NADH) in water solutions. A spin-coated film deposited on indium tin oxide electrode displays only one redox couple (at E1/2=0.78V). The films of [(C6H13S)8Pc]2Dy were modified chemically or electrochemically for the detection of reduced NADH in water solution. The modified film in the oxidized ([(C6H13S)8Pc]2Dy)+ form is believed to be reduced to its neutral form on interaction with NADH.
Journal of The Royal Society Interface 08/2008; 5(24):801-6. · 4.40 Impact Factor
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ABSTRACT: Thin films of bis[4,5,4,5,4,5,4,5]-octakis(hexylthiophthalocyanine) of lutetium(III) were prepared by spin coating at different speeds in the range of 2000–6000 rpm. The films undergo phase transition on heat treatment at temperatures above 120 C and the formation of a mesophase. The Q-bands in the visible absorption spectra of the films are broader and become red shifted compared to ones obtained for molecules in chloroform solution. Heat treatment produces molecular ordering, which is believed to be due to the edge-to-edge interaction between neighboring Pc moieties. Reduced film thickness and changes in optical constants are also attributed to thermally induced molecular reorganization corresponding to the liquid crystalline phase. AFM and polarized microscopy images are consistent with the phase transformations.
Journal of Materials Science Materials in Electronics 01/2004; 15(9):623-628. · 1.08 Impact Factor
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ABSTRACT: Vapour sensing properties of spin-coated films of mesogenic octa-substituted phthalocyanine derivatives MPcR8, where M = Ni(II), R = –S(CH2)11CH3, –SCH(CH2OC12H25)2, –S(CH2CH2O)3CH3 were investigated using spectroscopic ellipsometry, Raman spectroscopy and surface plasmon resonance (SPR) technique. Solvent molecules with saturated CC bonds such as chloroform are found to have formed hydrogen bonds with alkyl chains of the substituents of phthalocyanine molecules. The sensor response to aromatic compounds such as benzene is, on the other hand, believed to be the consequence of their π–π interaction with the conjugated phthalocyanine ring.
Sensors and Actuators B: Chemical.
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ABSTRACT: In this work, the investigation of structural features, spectral and electrical properties of films of nickel phthalocyanine (NiPcR8) and lutetium bisphthalocyanine (Lu(PcR8)2), where R = SC6H13, is carried out. The differences in structural organization of the heated and unheated films were stated. These differences in structural organization in their turn are found to influence the electrical properties of the films.
Materials Chemistry and Physics.
