WorldWideScience

Sample records for voltage-sensitive dye imaging

  1. Voltage-sensitive dye imaging of transcranial magnetic stimulation-induced intracortical dynamics.

    Science.gov (United States)

    Kozyrev, Vladislav; Eysel, Ulf T; Jancke, Dirk

    2014-09-16

    Transcranial magnetic stimulation (TMS) is widely used in clinical interventions and basic neuroscience. Additionally, it has become a powerful tool to drive plastic changes in neuronal networks. However, highly resolved recordings of the immediate TMS effects have remained scarce, because existing recording techniques are limited in spatial or temporal resolution or are interfered with by the strong TMS-induced electric field. To circumvent these constraints, we performed optical imaging with voltage-sensitive dye (VSD) in an animal experimental setting using anaesthetized cats. The dye signals reflect gradual changes in the cells' membrane potential across several square millimeters of cortical tissue, thus enabling direct visualization of TMS-induced neuronal population dynamics. After application of a single TMS pulse across visual cortex, brief focal activation was immediately followed by synchronous suppression of a large pool of neurons. With consecutive magnetic pulses (10 Hz), widespread activity within this "basin of suppression" increased stepwise to suprathreshold levels and spontaneous activity was enhanced. Visual stimulation after repetitive TMS revealed long-term potentiation of evoked activity. Furthermore, loss of the "deceleration-acceleration" notch during the rising phase of the response, as a signature of fast intracortical inhibition detectable with VSD imaging, indicated weakened inhibition as an important driving force of increasing cortical excitability. In summary, our data show that high-frequency TMS changes the balance between excitation and inhibition in favor of an excitatory cortical state. VSD imaging may thus be a promising technique to trace TMS-induced changes in excitability and resulting plastic processes across cortical maps with high spatial and temporal resolutions.

  2. Imaging Neuronal Seal Resistance on Silicon Chip using Fluorescent Voltage-Sensitive Dye

    Science.gov (United States)

    Braun, Dieter; Fromherz, Peter

    2004-01-01

    The electrical sheet resistance between living cells grown on planar electronic contacts of semiconductors or metals is a crucial parameter for bioelectronic devices. It determines the strength of electrical signal transduction from cells to chips and from chips to cells. We measured the sheet resistance by applying AC voltage to oxidized silicon chips and by imaging the voltage change across the attached cell membrane with a fluorescent voltage-sensitive dye. The phase map of voltage change was fitted with a planar core-coat conductor model using the sheet resistance as a free parameter. For nerve cells from rat brain on polylysine as well as for HEK293 cells and MDCK cells on fibronectin we find a similar sheet resistance of 10 MΩ. Taking into account the independently measured distance of 50 nm between chip and membrane for these cells, we obtain a specific resistance of 50 Ωcm that is indistinguishable from bulk electrolyte. On the other hand, the sheet resistance for erythrocytes on polylysine is far higher, at ∼1.5 GΩ. Considering the distance of 10 nm, the specific resistance in the narrow cleft is enhanced to 1500 Ωcm. We find this novel optical method to be a convenient tool to optimize the interface between cells and chips for bioelectronic devices. PMID:15298937

  3. Comparison of two voltage-sensitive dyes and their suitability for long-term imaging of neuronal activity.

    Directory of Open Access Journals (Sweden)

    Stephanie Preuss

    Full Text Available One of the key approaches for studying neural network function is the simultaneous measurement of the activity of many neurons. Voltage-sensitive dyes (VSDs simultaneously report the membrane potential of multiple neurons, but often have pharmacological and phototoxic effects on neuronal cells. Yet, to study the homeostatic processes that regulate neural network function long-term recordings of neuronal activities are required. This study aims to test the suitability of the VSDs RH795 and Di-4-ANEPPS for optically recording pattern generating neurons in the stomatogastric nervous system of crustaceans with an emphasis on long-term recordings of the pyloric central pattern generator. We demonstrate that both dyes stain pyloric neurons and determined an optimal concentration and light intensity for optical imaging. Although both dyes provided sufficient signal-to-noise ratio for measuring membrane potentials, Di-4-ANEPPS displayed a higher signal quality indicating an advantage of this dye over RH795 when small neuronal signals need to be recorded. For Di-4-ANEPPS, higher dye concentrations resulted in faster and brighter staining. Signal quality, however, only depended on excitation light strength, but not on dye concentration. RH795 showed weak and slowly developing phototoxic effects on the pyloric motor pattern as well as slow bleaching of the staining and is thus the better choice for long-term experiments. Low concentrations and low excitation intensities can be used as, in contrast to Di-4-ANEPPS, the signal-to-noise ratio was independent of excitation light strength. In summary, RH795 and Di-4-ANEPPS are suitable for optical imaging in the stomatogastric nervous system of crustaceans. They allow simultaneous recording of the membrane potential of multiple neurons with high signal quality. While Di-4-ANEPPS is better suited for short-term experiments that require high signal quality, RH795 is a better candidate for long-term experiments

  4. In Vivo Mesoscopic Voltage-Sensitive Dye Imaging of Brain Activation

    Science.gov (United States)

    Tang, Qinggong; Tsytsarev, Vassiliy; Frank, Aaron; Wu, Yalun; Chen, Chao-Wei; Erzurumlu, Reha S.; Chen, Yu

    2016-04-01

    Functional mapping of brain activity is important in elucidating how neural networks operate in the living brain. The whisker sensory system of rodents is an excellent model to study peripherally evoked neural activity in the central nervous system. Each facial whisker is represented by discrete modules of neurons all along the pathway leading to the neocortex. These modules are called “barrels” in layer 4 of the primary somatosensory cortex. Their location (approximately 300-500 μm below cortical surface) allows for convenient imaging of whisker-evoked neural activity in vivo. Fluorescence laminar optical tomography (FLOT) provides depth-resolved fluorescence molecular information with an imaging depth of a few millimeters. Angled illumination and detection configurations can improve both resolution and penetration depth. We applied angled FLOT (aFLOT) to record 3D neural activities evoked in the whisker system of mice by deflection of a single whisker in vivo. A 100 μm capillary and a pair of microelectrodes were inserted to the mouse brain to test the capability of the imaging system. The results show that it is possible to obtain 3D functional maps of the sensory periphery in the brain. This approach can be broadly applicable to functional imaging of other brain structures.

  5. Fast voltage-sensitive dye imaging of excitatory and inhibitory synaptic transmission in the rat granular retrosplenial cortex.

    Science.gov (United States)

    Nixima, Ken'ichi; Okanoya, Kazuo; Ichinohe, Noritaka; Kurotani, Tohru

    2017-09-01

    Rodent granular retrosplenial cortex (GRS) has dense connections between the anterior thalamic nuclei (ATN) and hippocampal formation. GRS superficial pyramidal neurons exhibit distinctive late spiking (LS) firing property and form patchy clusters with prominent apical dendritic bundles. The aim of this study was to investigate spatiotemporal dynamics of signal transduction in the GRS induced by ATN afferent stimulation by using fast voltage-sensitive dye imaging in rat brain slices. In coronal slices, layer 1a stimulation, which presumably activated thalamic fibers, evoked propagation of excitatory synaptic signals from layers 2-4 to layers 5-6 in a direction perpendicular to the layer axis, followed by transverse signal propagation within each layer. In the presence of ionotropic glutamate receptor antagonists, inhibitory responses were observed in superficial layers, induced by direct activation of inhibitory interneurons in layer 1. In horizontal slices, excitatory signals in deep layers propagated transversely mainly from posterior to anterior via superficial layers. Cortical inhibitory responses upon layer 1a stimulation in horizontal slices were weaker than those in the coronal slices. Observed differences between coronal and horizontal planes suggest anisotropy of the intracortical circuitry. In conclusion, ATN inputs are processed differently in coronal and horizontal planes of the GRS and then conveyed to other cortical areas. In both planes, GRS superficial layers play an important role in signal propagation, which suggests that superficial neuronal cascade is crucial in the integration of multiple information sources.NEW & NOTEWORTHY Superficial neurons in the rat granular retrosplenial cortex (GRS) show distinctive late-spiking (LS) firing property. However, little is known about spatiotemporal dynamics of signal transduction in the GRS. We demonstrated LS neuron network relaying thalamic inputs to deep layers and anisotropic distribution of inhibition

  6. Potassium Sensitive Optical Nanosensors Containing Voltage Sensitive Dyes.

    Science.gov (United States)

    Xie, Xiaojiang; Gutiérrez, Agustín; Trofimov, Valentin; Szilagyi, Istvan; Soldati, Thierry; Bakker, Eric

    2015-01-01

    lonophore-based ion-selective optical nanosensors have been explored for a number of years. Voltage sensitive dyes (VSDs) have been introduced into this type of sensors only very recently, forming a new class of analytical tools. Here, K(+)-sensitive nanospheres incorporating a lipophilic VSD were successfully fabricated and characterized. The nanosensors were readily delivered into the social amoeba Dictyostelium discoideum in a non-invasive manner, forming a promising new platform for intracellular ion quantification and imaging.

  7. Recording membrane potential changes through photoacoustic voltage sensitive dye

    DEFF Research Database (Denmark)

    Zhang, Haichong K.; Kang, Jeeun; Yan, Ping

    2017-01-01

    systems for external detection. In contrast, photoacoustic (PA) imaging, an emerging modality, is capable of deep tissue, noninvasive imaging by combining near infrared light excitation and ultrasound detection. In this work, we develop the theoretical concept whereby the voltage-dependent quenching......Monitoring of the membrane potential is possible using voltage sensitive dyes (VSD), where fluorescence intensity changes in response to neuronal electrical activity. However, fluorescence imaging is limited by depth of penetration and high scattering losses, which leads to low sensitivity in vivo...... the experimental PA intensity change depends on fluorescence and absorbance properties of the dye. These results not only demonstrate the voltage sensing capability of the dye, but also indicate the necessity of considering both fluorescence and absorbance spectral sensitivities in order to optimize...

  8. Palette of fluorinated voltage-sensitive hemicyanine dyes

    Science.gov (United States)

    Yan, Ping; Acker, Corey D.; Zhou, Wen-Liang; Lee, Peter; Bollensdorff, Christian; Negrean, Adrian; Lotti, Jacopo; Sacconi, Leonardo; Antic, Srdjan D.; Kohl, Peter; Mansvelder, Huibert D.; Pavone, Francesco S.; Loew, Leslie M.

    2012-01-01

    Optical recording of membrane potential permits spatially resolved measurement of electrical activity in subcellular regions of single cells, which would be inaccessible to electrodes, and imaging of spatiotemporal patterns of action potential propagation in excitable tissues, such as the brain or heart. However, the available voltage-sensitive dyes (VSDs) are not always spectrally compatible with newly available optical technologies for sensing or manipulating the physiological state of a system. Here, we describe a series of 19 fluorinated VSDs based on the hemicyanine class of chromophores. Strategic placement of the fluorine atoms on the chromophores can result in either blue or red shifts in the absorbance and emission spectra. The range of one-photon excitation wavelengths afforded by these new VSDs spans 440–670 nm; the two-photon excitation range is 900–1,340 nm. The emission of each VSD is shifted by at least 100 nm to the red of its one-photon excitation spectrum. The set of VSDs, thus, affords an extended toolkit for optical recording to match a broad range of experimental requirements. We show the sensitivity to voltage and the photostability of the new VSDs in a series of experimental preparations ranging in scale from single dendritic spines to whole heart. Among the advances shown in these applications are simultaneous recording of voltage and calcium in single dendritic spines and optical electrophysiology recordings using two-photon excitation above 1,100 nm. PMID:23169660

  9. 'Blue' voltage-sensitive dyes for studying spatiotemporal dynamics in the brain: visualizing cortical waves.

    Science.gov (United States)

    Geng, Xinling; Wu, Jian-Young

    2017-07-01

    Among many distinct contributions made by Amiram Grinvald's group, the "Blue dyes" is a special gift for visualizing cortical population neuronal activity. The excitation wavelength of blue dyes has minimal overlap with the absorption of hemoglobin, and hence has minimal pulsation artifacts. This advantage leads to high signal-to-noise ratio optical recordings of cortical activity, with sensitivity as good as that of local field potential recordings. High sensitivity imaging allows for recording of spontaneous and evoked activity in single trials without spatial or temporal averaging, and has benefitted many scientists in their research projects. Single trial recording is particularly important for studying the cortex, because spontaneous and ongoing activities interact with sensory evoked events, creating rich dynamics in the wave patterns. Signal averaging in space and time would diminish the dynamic components in the patterns. Here, we discuss how the blue dyes help to achieve high-sensitivity voltage-sensitive dye imaging of spontaneous and evoked cortical activities. Spontaneous cortical activity has a constantly changing spatial pattern and temporal frequency, making it impossible to average in space and time. Amiran Grinvald's invention of blue dyes made it possible to examine the spatiotemporal patterns of cortical dynamics, about 15 years before the first useful genetically coded voltage proteins became available.

  10. Spectral Properties and Orientation of Voltage-Sensitive Dyes in Lipid Membranes

    KAUST Repository

    Matson, Maria

    2012-07-24

    Voltage-sensitive dyes are frequently used for probing variations in the electric potential across cell membranes. The dyes respond by changing their spectral properties: measured as shifts of wavelength of absorption or emission maxima or as changes of absorption or fluorescence intensity. Although such probes have been studied and used for decades, the mechanism behind their voltage sensitivity is still obscure. We ask whether the voltage response is due to electrochromism as a result of direct field interaction on the chromophore or to solvatochromism, which is the focus of this study, as result of changed environment or molecular alignment in the membrane. The spectral properties of three styryl dyes, di-4-ANEPPS, di-8-ANEPPS, and RH421, were investigated in solvents of varying polarity and in model membranes using spectroscopy. Using quantum mechanical calculations, the spectral dependence of monomer and dimer ANEPPS on solvent properties was modeled. Also, the kinetics of binding to lipid membranes and the binding geometry of the probe molecules were found relevant to address. The spectral properties of all three probes were found to be highly sensitive to the local environment, and the probes are oriented nearly parallel with the membrane normal. Slow binding kinetics and scattering in absorption spectra indicate, especially for di-8-ANEPPS, involvement of aggregation. On the basis of the experimental spectra and time-dependent density functional theory calculations, we find that aggregate formation may contribute to the blue-shifts seen for the dyes in decanol and when bound to membrane models. In conclusion, solvatochromic and other intermolecular interactions effects also need to be included when considering electrochromic response voltage-sensitive dyes. © 2012 American Chemical Society.

  11. Voltage-sensitive styryl dyes as singlet oxygen targets on the surface of bilayer lipid membrane.

    Science.gov (United States)

    Sokolov, V S; Gavrilchik, A N; Kulagina, A O; Meshkov, I N; Pohl, P; Gorbunova, Yu G

    2016-08-01

    Photosensitizers are widely used as photodynamic therapeutic agents killing cancer cells by photooxidation of their components. Development of new effective photosensitive molecules requires profound knowledge of possible targets for reactive oxygen species, especially for its singlet form. Here we studied photooxidation of voltage-sensitive styryl dyes (di-4-ANEPPS, di-8-ANEPPS, RH-421 and RH-237) by singlet oxygen on the surface of bilayer lipid membranes commonly used as cell membrane models. Oxidation was induced by irradiation of a photosensitizer (aluminum phthalocyanine tetrasulfonate) and monitored by the change of dipole potential on the surface of the membrane. We studied the drop of the dipole potential both in the case when the dye molecules were adsorbed on the same side of the lipid bilayer as the photosensitizer (cis-configuration) and in the case when they were adsorbed on the opposite side (trans-configuration). Based on a simple model, we determined the rate of oxidation of the dyes from the kinetics of change of the potential during and after irradiation. This rate is proportional to steady-state concentration of singlet oxygen in the membrane under irradiation. Comparison of the oxidation rates of various dyes reveals that compounds of ANEPPS series are more sensitive to singlet oxygen than RH type dyes, indicating that naphthalene group is primarily responsible for their oxidation. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Transmembrane potential measurements on plant cells using the voltage-sensitive dye ANNINE-6.

    Science.gov (United States)

    Flickinger, Bianca; Berghöfer, Thomas; Hohenberger, Petra; Eing, Christian; Frey, Wolfgang

    2010-11-01

    The charging of the plasma membrane is a necessary condition for the generation of an electric-field-induced permeability increase of the plasmalemma, which is usually explained by the creation and the growth of aqueous pores. For cells suspended in physiological buffers, the time domain of membrane charging is in the submicrosecond range. Systematic measurements using Nicotiana tabacum L. cv. Bright Yellow 2 (BY-2) protoplasts stained with the fast voltage-sensitive fluorescence dye ANNINE-6 have been performed using a pulsed laser fluorescence microscopy setup with a time resolution of 5 ns. A clear saturation of the membrane voltage could be measured, caused by a strong membrane permeability increase, commonly explained by enhanced pore formation, which prevents further membrane charging by external electric field exposure. The field strength dependence of the protoplast's transmembrane potential V (M) shows strong asymmetric saturation characteristics due to the high resting potential of the plants plasmalemma. At the pole of the hyperpolarized hemisphere of the cell, saturation starts at an external field strength of 0.3 kV/cm, resulting in a measured transmembrane voltage shift of ∆V(M) = -150 mV, while on the cathodic (depolarized) cell pole, the threshold for enhanced pore formation is reached at a field strength of approximately 1.0 kV/cm and ∆V(M) = 450 mV, respectively. From this asymmetry of the measured maximum membrane voltage shifts, the resting potential of BY-2 protoplasts at the given experimental conditions can be determined to V(R) = -150 mV. Consequently, a strong membrane permeability increase occurs when the membrane voltage diverges |V(M)| = 300 mV from the resting potential of the protoplast. The largest membrane voltage change at a given external electric field occurs at the cell poles. The azimuthal dependence of the transmembrane potential, measured in angular intervals of 10° along the circumference of the cell, shows a flattening

  13. Optical properties of voltage sensitive hemicyanine dyes of variable hydrophobicity confined within surfactant micelles

    Science.gov (United States)

    Naeem, Kashif; Naseem, Bushra; Shah, S. S.; Shah, Syed W. H.

    2017-11-01

    The optical properties of amphiphilic hemicyanine dyes with variable hydrophobicity, confined within anionic micelles of sodium dodecylbenzenesulfonate (NaDDBS) have been studied by UV–visible absorption spectroscopy. The confinement constant, K conf has been determined for each entrapped dye. The ion-pair formation between dye and surfactant causes a decline in electronic transition energy (ΔE T) when dye alkyl chains are smaller due to stabilization of both the ground and excited state. ΔE T values gradually increase with increase in dye hydrophobicity that hampers the electrostatic interaction with dialkylammonium moiety and consequently excited state stabilization is compromised. The average number of dye molecules trapped in a single micelle was also determined. The negative values of Gibbs free energy indicate that the dye entrapment within micelles is energetically favored. These findings have significance for developing functional materials with peculiar luminescent properties, especially for more effective probing of complex biological systems.

  14. Spatio-temporal Distribution of Epileptiform Potentials in the Hippocampal Slice: Recordings with Voltage-sensitive Dyes.

    Science.gov (United States)

    Albowitz, Birgit; Kuhnt, Ulrich

    1991-06-01

    Voltage-sensitive dyes and fast optical recording techniques were used to monitor the spatio-temporal activity pattern of epileptiform potentials in hippocampal slices from guinea pigs. Epileptiform potentials were induced by adding 4-aminopyridine to the bath solution and applying single pulse stimulation either to the stratum pyramidale of area CA3 or to the stratum radiatum of area CA1. Optical activity as well as intra- or extracellular electrical activity were recorded from area CA1. There was a good correlation between optical and intracellular records from the same site. The spatio-temporal activity pattern of control and epileptiform potentials elicited by stimulation of CA1 was similar for the initial part of the potential. Then, epileptiform changes became apparent throughout the vertical extent of pyramidal neurons. Qualitative changes occurred in the stratum moleculare, reflecting activity of apical dendrites, such changes occurred even more strongly in the stratum oriens, reflecting activity of basal dendrites. The activity in the stratum oriens occurred relatively late, so that it cannot account for the initiation of epileptic discharges. It might, however, play an important role in the synchronization and spread of epileptiform potentials. The investigation of the horizontal distribution of potentials throughout the entire area CA1 indicates that different mechanisms are involved in the spread of epileptiform activity elicited by stimulation of CA1 and stimulation of CA3.

  15. In Vivo Voltage-Sensitive Dye Study of Lateral Spreading of Cortical Activity in Mouse Primary Visual Cortex Induced by a Current Impulse.

    Science.gov (United States)

    Fehérvári, Tamás Dávid; Okazaki, Yuka; Sawai, Hajime; Yagi, Tetsuya

    2015-01-01

    In the mammalian primary visual cortex (V1), lateral spreading of excitatory potentials is believed to be involved in spatial integrative functions, but the underlying cortical mechanism is not well understood. Visually-evoked population-level responses have been shown to propagate beyond the V1 initial activation site in mouse, similar to higher mammals. Visually-evoked responses are, however, affected by neuronal circuits prior to V1 (retina, LGN), making the separate analysis of V1 difficult. Intracortical stimulation eliminates these initial processing steps. We used in vivo RH1691 voltage-sensitive dye (VSD) imaging and intracortical microstimulation in adult C57BL/6 mice to elucidate the spatiotemporal properties of population-level signal spreading in V1 cortical circuits. The evoked response was qualitatively similar to that measured in single-cell electrophysiological experiments in rodents: a fast transient fluorescence peak followed by a fast and a slow decrease or hyperpolarization, similar to EPSP and fast and slow IPSPs in single cells. The early cortical response expanded at speeds commensurate with long horizontal projections (at 5% of the peak maximum, 0.08-0.15 m/s) however, the bulk of the VSD signal propagated slowly (at half-peak maximum, 0.05-0.08 m/s) suggesting an important role of regenerative multisynaptic transmission through short horizontal connections in V1 spatial integrative functions. We also found a tendency for a widespread and fast cortical response suppression in V1, which was eliminated by GABAA-antagonists gabazine and bicuculline methiodide. Our results help understand the neuronal circuitry involved in lateral spreading in V1.

  16. In Vivo Voltage-Sensitive Dye Study of Lateral Spreading of Cortical Activity in Mouse Primary Visual Cortex Induced by a Current Impulse.

    Directory of Open Access Journals (Sweden)

    Tamás Dávid Fehérvári

    Full Text Available In the mammalian primary visual cortex (V1, lateral spreading of excitatory potentials is believed to be involved in spatial integrative functions, but the underlying cortical mechanism is not well understood. Visually-evoked population-level responses have been shown to propagate beyond the V1 initial activation site in mouse, similar to higher mammals. Visually-evoked responses are, however, affected by neuronal circuits prior to V1 (retina, LGN, making the separate analysis of V1 difficult. Intracortical stimulation eliminates these initial processing steps. We used in vivo RH1691 voltage-sensitive dye (VSD imaging and intracortical microstimulation in adult C57BL/6 mice to elucidate the spatiotemporal properties of population-level signal spreading in V1 cortical circuits. The evoked response was qualitatively similar to that measured in single-cell electrophysiological experiments in rodents: a fast transient fluorescence peak followed by a fast and a slow decrease or hyperpolarization, similar to EPSP and fast and slow IPSPs in single cells. The early cortical response expanded at speeds commensurate with long horizontal projections (at 5% of the peak maximum, 0.08-0.15 m/s however, the bulk of the VSD signal propagated slowly (at half-peak maximum, 0.05-0.08 m/s suggesting an important role of regenerative multisynaptic transmission through short horizontal connections in V1 spatial integrative functions. We also found a tendency for a widespread and fast cortical response suppression in V1, which was eliminated by GABAA-antagonists gabazine and bicuculline methiodide. Our results help understand the neuronal circuitry involved in lateral spreading in V1.

  17. A near-infrared fluorescent voltage-sensitive dye allows for moderate-throughput electrophysiological analyses of human induced pluripotent stem cell-derived cardiomyocytes

    Science.gov (United States)

    Lopez-Izquierdo, Angelica; Warren, Mark; Riedel, Michael; Cho, Scott; Lai, Shuping; Lux, Robert L.; Spitzer, Kenneth W.; Benjamin, Ivor J.; Jou, Chuanchau J.

    2014-01-01

    Human induced pluripotent stem cell-derived cardiomyocyte (iPSC-CM)-based assays are emerging as a promising tool for the in vitro preclinical screening of QT interval-prolonging side effects of drugs in development. A major impediment to the widespread use of human iPSC-CM assays is the low throughput of the currently available electrophysiological tools. To test the precision and applicability of the near-infrared fluorescent voltage-sensitive dye 1-(4-sulfanatobutyl)-4-{β[2-(di-n-butylamino)-6-naphthyl]butadienyl}quinolinium betaine (di-4-ANBDQBS) for moderate-throughput electrophysiological analyses, we compared simultaneous transmembrane voltage and optical action potential (AP) recordings in human iPSC-CM loaded with di-4-ANBDQBS. Optical AP recordings tracked transmembrane voltage with high precision, generating nearly identical values for AP duration (AP durations at 10%, 50%, and 90% repolarization). Human iPSC-CMs tolerated repeated laser exposure, with stable optical AP parameters recorded over a 30-min study period. Optical AP recordings appropriately tracked changes in repolarization induced by pharmacological manipulation. Finally, di-4-ANBDQBS allowed for moderate-throughput analyses, increasing throughput >10-fold over the traditional patch-clamp technique. We conclude that the voltage-sensitive dye di-4-ANBDQBS allows for high-precision optical AP measurements that markedly increase the throughput for electrophysiological characterization of human iPSC-CMs. PMID:25172899

  18. Voltage-sensitive rhodol with enhanced two-photon brightness.

    Science.gov (United States)

    Kulkarni, Rishikesh U; Kramer, Daniel J; Pourmandi, Narges; Karbasi, Kaveh; Bateup, Helen S; Miller, Evan W

    2017-03-14

    We have designed, synthesized, and applied a rhodol-based chromophore to a molecular wire-based platform for voltage sensing to achieve fast, sensitive, and bright voltage sensing using two-photon (2P) illumination. Rhodol VoltageFluor-5 (RVF5) is a voltage-sensitive dye with improved 2P cross-section for use in thick tissue or brain samples. RVF5 features a dichlororhodol core with pyrrolidyl substitution at the nitrogen center. In mammalian cells under one-photon (1P) illumination, RVF5 demonstrates high voltage sensitivity (28% ΔF/F per 100 mV) and improved photostability relative to first-generation voltage sensors. This photostability enables multisite optical recordings from neurons lacking tuberous sclerosis complex 1, Tsc1, in a mouse model of genetic epilepsy. Using RVF5, we show that Tsc1 KO neurons exhibit increased activity relative to wild-type neurons and additionally show that the proportion of active neurons in the network increases with the loss of Tsc1. The high photostability and voltage sensitivity of RVF5 is recapitulated under 2P illumination. Finally, the ability to chemically tune the 2P absorption profile through the use of rhodol scaffolds affords the unique opportunity to image neuronal voltage changes in acutely prepared mouse brain slices using 2P illumination. Stimulation of the mouse hippocampus evoked spiking activity that was readily discerned with bath-applied RVF5, demonstrating the utility of RVF5 and molecular wire-based voltage sensors with 2P-optimized fluorophores for imaging voltage in intact brain tissue.

  19. Feasibility of using RH795 dye for photoacoustic imaging of neuro-electrical activity

    Science.gov (United States)

    Rasheed, Nashaat; Cressman, John R.; Chitnis, Parag V.

    2017-02-01

    Currently, the most researched noninvasive approach for monitoring neuro-electrical activity involves opticalfluorescence imaging, which suffers from limited imaging penetration. We propose an alternative approach, photoacoustic imaging (PAI) of biopotentials, that relies on transient absorption of light by voltage-sensitive probes and subsequent generation/detection of ultrasound. PAI-based voltage imaging approach can offer the same advantages as the fluorescence imaging in terms of sensitivity and molecular specificity, but it also can significantly extend the imaging depth. In this pilot study we are investigating the feasibility of photoacoustically visualizing biopotentials in rat pheochromocytoma (PC12) cells tagged with voltage-sensitive styrylpyridinium dye, RH795. A change in the intramembrane potential was induced in PC12 cells by adding tetraphenylborate (TPB) to the cell culture. A custommade absorption spectrophotometer was used to verify the change in optical absorption of RH795 dye as a result of TPBinduced electrical fields. Absorption spectra recorded before and after the addition of 100 μM TPB exhibited a wavelength shift of the absorption peak (approximately 510 nm to 550 nm) as well as an increase in the overall magnitude of absorption in the wavelength range of 500-1000 nm. The absorption spectral measurements indicated that RH795 is a good candidate as a voltage-sensitive dye for photoacoustically tracking changes in cell-membrane potential.

  20. The Use of Ratiometric Fluorescence Measurements of the Voltage Sensitive Dye Di-4-ANEPPS to Examine Action Potential Characteristics and Drug Effects on Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes.

    Science.gov (United States)

    Hortigon-Vinagre, M P; Zamora, V; Burton, F L; Green, J; Gintant, G A; Smith, G L

    2016-12-01

    Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM) and higher throughput platforms have emerged as potential tools to advance cardiac drug safety screening. This study evaluated the use of high bandwidth photometry applied to voltage-sensitive fluorescent dyes (VSDs) to assess drug-induced changes in action potential characteristics of spontaneously active hiPSC-CM. Human iPSC-CM from 2 commercial sources (Cor.4U and iCell Cardiomyocytes) were stained with the VSD di-4-ANEPPS and placed in a specialized photometry system that simultaneously monitors 2 wavebands of emitted fluorescence, allowing ratiometric measurement of membrane voltage. Signals were acquired at 10 kHz and analyzed using custom software. Action potential duration (APD) values were normally distributed in cardiomyocytes (CMC) from both sources though the mean and variance differed significantly (APD 90 : 229 ± 15 ms vs 427 ± 49 ms [mean ± SD, P < 0.01]; average spontaneous cycle length: 0.99 ± 0.02 s vs 1.47 ± 0.35 s [mean ± SD, P < 0.01], Cor.4U vs iCell CMC, respectively). The 10-90% rise time of the AP (T rise ) was ∼6 ms and was normally distributed when expressed as 1/[Formula: see text] in both cell preparations. Both cell types showed a rate dependence analogous to that of adult human cardiac cells. Furthermore, nifedipine, ranolazine, and E4031 had similar effects on cardiomyocyte electrophysiology in both cell types. However, ranolazine and E4031 induced early after depolarization-like events and high intrinsic firing rates at lower concentrations in iCell CMC. These data show that VSDs provide a minimally invasive, quantitative, and accurate method to assess hiPSC-CM electrophysiology and detect subtle drug-induced effects for drug safety screening while highlighting a need to standardize experimental protocols across preparations. © The Author 2016. Published by Oxford University Press on behalf of the Society of

  1. Image analysis of dye stained patterns in soils

    Science.gov (United States)

    Bogner, Christina; Trancón y Widemann, Baltasar; Lange, Holger

    2013-04-01

    Quality of surface water and groundwater is directly affected by flow processes in the unsaturated zone. In general, it is difficult to measure or model water flow. Indeed, parametrization of hydrological models is problematic and often no unique solution exists. To visualise flow patterns in soils directly dye tracer studies can be done. These experiments provide images of stained soil profiles and their evaluation demands knowledge in hydrology as well as in image analysis and statistics. First, these photographs are converted to binary images classifying the pixels in dye stained and non-stained ones. Then, some feature extraction is necessary to discern relevant hydrological information. In our study we propose to use several index functions to extract different (ideally complementary) features. We associate each image row with a feature vector (i.e. a certain number of image function values) and use these features to cluster the image rows to identify similar image areas. Because images of stained profiles might have different reasonable clusterings, we calculate multiple consensus clusterings. An expert can explore these different solutions and base his/her interpretation of predominant flow mechanisms on quantitative (objective) criteria. The complete workflow from reading-in binary images to final clusterings has been implemented in the free R system, a language and environment for statistical computing. The calculation of image indices is part of our own package Indigo, manipulation of binary images, clustering and visualization of results are done using either build-in facilities in R, additional R packages or the LATEX system.

  2. Voltage-Sensitive Ion Channels Biophysics of Molecular Excitability

    CERN Document Server

    Leuchtag, H. Richard

    2008-01-01

    Voltage-sensitive ion channels are macromolecules embedded in the membranes of nerve and muscle fibers of animals. Because of their physiological functions, biochemical structures and electrical switching properties, they are at an intersection of biology, chemistry and physics. Despite decades of intensive research under the traditional approach of gated structural pores, the relation between the structure of these molecules and their function remains enigmatic. This book critically examines physically oriented approaches not covered in other ion-channel books. It looks at optical and thermal as well as electrical data, and at studies in the frequency domain as well as in the time domain. Rather than presenting the reader with only an option of mechanistic models at an inappropriate pseudo-macroscopic scale, it emphasizes concepts established in organic chemistry and condensed state physics. The book’s approach to the understanding of these unique structures breaks with the unproven view of ion channels as...

  3. Storable, thermally activated, near-infrared chemiluminescent dyes and dye-stained microparticles for optical imaging

    Science.gov (United States)

    Baumes, Jeffrey M.; Gassensmith, Jeremiah J.; Giblin, Jay; Lee, Jung-Jae; White, Alexander G.; Culligan, William J.; Leevy, W. Matthew; Kuno, Masaru; Smith, Bradley D.

    2010-12-01

    Imaging techniques are a vital part of clinical diagnostics, biomedical research and nanotechnology. Optical molecular imaging makes use of relatively harmless, low-energy light and technically straightforward instrumentation. Self-illuminating, chemiluminescent systems are particularly attractive because they have inherently high signal contrast due to the lack of background emission. Currently, chemiluminescence imaging involves short-lived molecular species that are not stored but are instead generated in situ, and they typically emit visible light, which does not penetrate far through heterogeneous biological media. Here, we describe a new paradigm for optical molecular imaging using squaraine rotaxane endoperoxides, interlocked fluorescent and chemiluminescent dye molecules that have a squaraine chromophore encapsulated inside a macrocycle endoperoxide. Squaraine rotaxane endoperoxides can be stored indefinitely at temperatures below -20 °C, but upon warming to body temperature they undergo a unimolecular chemical reaction and emit near-infrared light that can pass through a living mouse.

  4. Recent Developments in VSD Imaging of Small Neuronal Networks

    Science.gov (United States)

    Hill, Evan S.; Bruno, Angela M.; Frost, William N.

    2014-01-01

    Voltage-sensitive dye (VSD) imaging is a powerful technique that can provide, in single experiments, a large-scale view of network activity unobtainable with traditional sharp electrode recording methods. Here we review recent work using VSDs to study small networks and highlight several results from this approach. Topics covered include circuit…

  5. The allosteric site regulates the voltage sensitivity of muscarinic receptors.

    Science.gov (United States)

    Hoppe, Anika; Marti-Solano, Maria; Drabek, Matthäus; Bünemann, Moritz; Kolb, Peter; Rinne, Andreas

    2018-01-01

    Muscarinic receptors (M-Rs) for acetylcholine (ACh) belong to the class A of G protein-coupled receptors. M-Rs are activated by orthosteric agonists that bind to a specific site buried in the M-R transmembrane helix bundle. In the active conformation, receptor function can be modulated either by allosteric modulators, which bind to the extracellular receptor surface or by the membrane potential via an unknown mechanism. Here, we compared the modulation of M 1 -Rs and M 3 -Rs induced by changes in voltage to their allosteric modulation by chemical compounds. We quantified changes in receptor signaling in single HEK 293 cells with a FRET biosensor for the G q protein cycle. In the presence of ACh, M 1 -R signaling was potentiated by voltage, similarly to positive allosteric modulation by benzyl quinolone carboxylic acid. Conversely, signaling of M 3 -R was attenuated by voltage or the negative allosteric modulator gallamine. Because the orthosteric site is highly conserved among M-Rs, but allosteric sites vary, we constructed "allosteric site" M 3 /M 1 -R chimeras and analyzed their voltage dependencies. Exchanging the entire allosteric sites eliminated the voltage sensitivity of ACh responses for both receptors, but did not affect their modulation by allosteric compounds. Furthermore, a point mutation in M 3 -Rs caused functional uncoupling of the allosteric and orthosteric sites and abolished voltage dependence. Molecular dynamics simulations of the receptor variants indicated a subtype-specific crosstalk between both sites, involving the conserved tyrosine lid structure of the orthosteric site. This molecular crosstalk leads to receptor subtype-specific voltage effects. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Modelling of microcracks image treated with fluorescent dye

    Science.gov (United States)

    Glebov, Victor; Lashmanov, Oleg U.

    2015-06-01

    The main reasons of catastrophes and accidents are high level of wear of equipment and violation of the production technology. The methods of nondestructive testing are designed to find out defects timely and to prevent break down of aggregates. These methods allow determining compliance of object parameters with technical requirements without destroying it. This work will discuss dye penetrant inspection or liquid penetrant inspection (DPI or LPI) methods and computer model of microcracks image treated with fluorescent dye. Usually cracks on image look like broken extended lines with small width (about 1 to 10 pixels) and ragged edges. The used method of inspection allows to detect microcracks with depth about 10 or more micrometers. During the work the mathematical model of image of randomly located microcracks treated with fluorescent dye was created in MATLAB environment. Background noises and distortions introduced by the optical systems are considered in the model. The factors that have influence on the image are listed below: 1. Background noise. Background noise is caused by the bright light from external sources and it reduces contrast on the objects edges. 2. Noises on the image sensor. Digital noise manifests itself in the form of randomly located points that are differing in their brightness and color. 3. Distortions caused by aberrations of optical system. After passing through the real optical system the homocentricity of the bundle of rays is violated or homocentricity remains but rays intersect at the point that doesn't coincide with the point of the ideal image. The stronger the influence of the above-listed factors, the worse the image quality and therefore the analysis of the image for control of the item finds difficulty. The mathematical model is created using the following algorithm: at the beginning the number of cracks that will be modeled is entered from keyboard. Then the point with random position is choosing on the matrix whose size is

  7. Evaluation of chemical fluorescent dyes as a protein conjugation partner for live cell imaging.

    Directory of Open Access Journals (Sweden)

    Yoko Hayashi-Takanaka

    Full Text Available To optimize live cell fluorescence imaging, the choice of fluorescent substrate is a critical factor. Although genetically encoded fluorescent proteins have been used widely, chemical fluorescent dyes are still useful when conjugated to proteins or ligands. However, little information is available for the suitability of different fluorescent dyes for live imaging. We here systematically analyzed the property of a number of commercial fluorescent dyes when conjugated with antigen-binding (Fab fragments directed against specific histone modifications, in particular, phosphorylated H3S28 (H3S28ph and acetylated H3K9 (H3K9ac. These Fab fragments were conjugated with a fluorescent dye and loaded into living HeLa cells. H3S28ph-specific Fab fragments were expected to be enriched in condensed chromosomes, as H3S28 is phosphorylated during mitosis. However, the degree of Fab fragment enrichment on mitotic chromosomes varied depending on the conjugated dye. In general, green fluorescent dyes showed higher enrichment, compared to red and far-red fluorescent dyes, even when dye:protein conjugation ratios were similar. These differences are partly explained by an altered affinity of Fab fragment after dye-conjugation; some dyes have less effect on the affinity, while others can affect it more. Moreover, red and far-red fluorescent dyes tended to form aggregates in the cytoplasm. Similar results were observed when H3K9ac-specific Fab fragments were used, suggesting that the properties of each dye affect different Fab fragments similarly. According to our analysis, conjugation with green fluorescent dyes, like Alexa Fluor 488 and Dylight 488, has the least effect on Fab affinity and is the best for live cell imaging, although these dyes are less photostable than red fluorescent dyes. When multicolor imaging is required, we recommend the following dye combinations for optimal results: Alexa Fluor 488 (green, Cy3 (red, and Cy5 or CF640 (far-red.

  8. Polyester Fabric's Fluorescent Dyeing in Supercritical Carbon Dioxide and its Fluorescence Imaging.

    Science.gov (United States)

    Xiong, Xiaoqing; Xu, Yanyan; Zheng, Laijiu; Yan, Jun; Zhao, Hongjuan; Zhang, Juan; Sun, Yanfeng

    2017-03-01

    As one of the most important coumarin-like dyes, disperse fluorescent Yellow 82 exhibits exceptionally large two-photon effects. Here, it was firstly introduced into the supercritical CO2 dyeing polyester fabrics in this work. Results of the present work showed that the dyeing parameters such as the dyeing time, pressure and temperature had remarkable influences on the color strength of fabrics. The optimized dyeing condition in supercritical CO2 dyeing has been proposed that the dyeing time was 60 min; the pressure was 25 MPa and the temperature was 120 °C. As a result, acceptable products were obtained with the wash and rub fastness rating at 5 or 4-5. The polyester fabrics dyed with fluorescent dyes can be satisfied for the requirement of manufacturing warning clothing. Importantly, the confocal microscopy imaging technology was successfully introduced into textile fields to observe the distribution and fluorescence intensity of disperse fluorescent Yellow 82 on polyester fabrics. As far as we know, this is the first report about supercritical CO2 dyeing polyester fabrics based on disperse fluorescent dyes. It will be very helpful for the further design of new fluorescent functional dyes suitable for supercritical CO2 dyeing technique.

  9. Multicolour single molecule imaging in cells with near infra-red dyes.

    Directory of Open Access Journals (Sweden)

    Christopher J Tynan

    Full Text Available The autofluorescence background of biological samples impedes the detection of single molecules when imaging. The most common method of reducing the background is to use evanescent field excitation, which is incompatible with imaging beyond the surface of biological samples. An alternative would be to use probes that can be excited in the near infra-red region of the spectrum, where autofluorescence is low. Such probes could also increase the number of labels that can be imaged in multicolour single molecule microscopes. Despite being widely used in ensemble imaging, there is a currently a shortage of information available for selecting appropriate commercial near infra-red dyes for single molecule work. It is therefore important to characterise available near infra-red dyes relevant to multicolour single molecule imaging.A range of commercially available near infra-red dyes compatible with multi-colour imaging was screened to find the brightest and most photostable candidates. Image series of immobilised samples of the brightest dyes (Alexa 700, IRDye 700DX, Alexa 790 and IRDye 800CW were analysed to obtain the mean intensity of single dye molecules, their photobleaching rates and long period blinking kinetics. Using the optimum dye pair, we have demonstrated for the first time widefield, multi-colour, near infra-red single molecule imaging using a supercontinuum light source in MCF-7 cells.We have demonstrated that near infra-red dyes can be used to avoid autofluorescence background in samples where restricting the illumination volume of visible light fails or is inappropriate. We have also shown that supercontinuum sources are suited to single molecule multicolour imaging throughout the 470-1000 nm range. Our measurements of near infra-red dye properties will enable others to select optimal dyes for single molecule imaging.

  10. Second and third generation voltage-sensitive fluorescent proteins for monitoring membrane potential

    Directory of Open Access Journals (Sweden)

    Amelie Perron

    2009-06-01

    Full Text Available Over the last decade, optical neuroimaging methods have been enriched by engineered biosensors derived from fluorescent protein (FP reporters fused to protein detectors that convert physiological signals into changes of intrinsic FP fluorescence. These FP-based indicators are genetically encoded, and hence targetable to specific cell populations within networks of heterologous cell types. Among this class of biosensors, the development of optical probes for membrane potential is both highly desirable and challenging. A suitable FP voltage sensor would indeed be a valuable tool for monitoring the activity of thousands of individual neurons simultaneously in a non-invasive manner. Previous prototypic genetically-encoded FP voltage indicators achieved a proof of principle but also highlighted several difficulties such as poor cell surface targeting and slow kinetics. Recently, we developed a new series of FRET-based Voltage-Sensitive Fluorescent Proteins (VSFPs, referred to as VSFP2s, with efficient targeting to the plasma membrane and high responsiveness to membrane potential signaling in excitable cells. In addition to these FRET-based voltage sensors, we also generated a third series of probes consisting of single FPs with response kinetics suitable for the optical imaging of fast neuronal signals. These newly available genetically-encoded reporters for membrane potential will be instrumental for future experimental approaches directed toward the understanding of neuronal network dynamics and information processing in the brain. Here, we review the development and current status of these novel fluorescent probes.

  11. Deep-red emissive crescent-shaped fluorescent dyes: substituent effect on live cell imaging.

    Science.gov (United States)

    Liu, Weimin; Zhou, Bingjiang; Niu, Guangle; Ge, Jiechao; Wu, Jiasheng; Zhang, Hongyan; Xu, Haitao; Wang, Pengfei

    2015-04-08

    A series of crescent-shaped fluorescent dyes (CP1-CP6) were synthesized by hybridizing coumarin and pyronin moieties with different amino substituents at both ends. The molecular structures and photophysical properties of these fluorescent dyes were investigated through X-ray diffraction, absorption spectroscopy, and fluorescence spectroscopy. Results show that the fluorescent dyes exhibited crescent-shaped structures, deep-red emissions (approximately 650 nm), and significant Stokes shifts. In live-cell-imaging experiments, CP1 stains mitochondria, whereas CP3 and CP6 stain the lysosomes in a cytoplasm and the RNA in nucleoli. The relationships between different amino substituent groups and the imaging properties of CP dyes were discussed as well. Additionally, findings from the cytotoxicity and photostability experiments on living cells indicated the favorable biocompatibility and high photostability of the CP dyes.

  12. Real-time histological imaging of kidneys stained with food dyes using multiphoton microscopy.

    Science.gov (United States)

    Nagao, Yasuaki; Kimura, Kazushi; Wang, Shujie; Fujiwara, Takeshi; Mizoguchi, Akira

    2015-10-01

    We have developed a real-time imaging technique for diagnosis of kidney diseases which is composed of two steps, staining renal cells safely with food dyes and optical sectioning of living renal tissue to obtain histological images by multiphoton microscopy (MPM). Here, we demonstrated that the MPM imaging with food dyes, including erythrosine and indigo carmine, could be used as fluorescent agents to visualize renal functions and structures such as glomerular bloodstreams, glomerular filtration, and morphology of glomeruli and renal tubules. We also showed that the kidneys of IgA nephropathy model-mice stained with the food dyes presented histopathological characteristics different from those observed in normal kidneys. The use of the food dyes enhances the quality of tissue images obtained by MPM and offers the potential to contribute to a clinical real-time diagnosis of kidney diseases. © 2015 Wiley Periodicals, Inc.

  13. Ex-vivo imaging of excised tissue using vital dyes and confocal microscopy

    Science.gov (United States)

    Johnson, Simon; Rabinovitch, Peter

    2012-01-01

    Vital dyes routinely used for staining cultured cells can also be used to stain and image live tissue slices ex-vivo. Staining tissue with vital dyes allows researchers to collect structural and functional data simultaneously and can be used for qualitative or quantitative fluorescent image collection. The protocols presented here are useful for structural and functional analysis of viable properties of cells in intact tissue slices, allowing for the collection of data in a structurally relevant environment. With these protocols, vital dyes can be applied as a research tool to disease processes and properties of tissue not amenable to cell culture based studies. PMID:22752953

  14. Locally Excited State-Charge Transfer State Coupled Dyes as Optically Responsive Neuron Firing Probes.

    Science.gov (United States)

    Sirbu, Dumitru; Butcher, John B; Waddell, Paul G; Andras, Peter; Benniston, Andrew C

    2017-10-17

    A selection of NIR-optically responsive neuron probes was produced comprising of a donor julolidyl group connected to a BODIPY core and several different styryl and vinylpyridinyl derived acceptor moieties. The strength of the donor-acceptor interaction was systematically modulated by altering the electron withdrawing nature of the aryl unit. The fluorescence quantum yield was observed to decrease as the electron withdrawing effect of the aryl subunit increased in line with changes of the Hammett parameter. The effectiveness of these fluorophores as optically responsive dyes for neuronal imaging was assessed by measuring the toxicity and signal-to-noise ratio (SNR) of each dye. A great improvement of SNR was obtained when compared to the first-generation BODIPY-based voltage sensitive dyes with concomitant toxicity decrease. The mechanism for the optical response is disparate from conventional cyanine-based dyes, opening up a new way to produce effective voltage sensitive dyes that respond well into the NIR region. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Spectral imaging of multi-color chromogenic dyes in pathological specimens.

    NARCIS (Netherlands)

    Macville, M.V.E.; Laak, J.A.W.M. van der; Speel, E.J.; Katzir, N.; Garini, Y.; Soenksen, D.; McNamara, G.; Wilde, P.C.M. de; Hanselaar, A.G.J.M.; Hopman, A.H.N.; Ried, T.

    2001-01-01

    We have investigated the use of spectral imaging for multi-color analysis of permanent cytochemical dyes and enzyme precipitates on cytopathological specimens. Spectral imaging is based on Fourier-transform spectroscopy and digital imaging. A pixel-by-pixel spectrum-based color classification is

  16. Nanoimprinted distributed feedback dye laser sensor for real-time imaging of small molecule diffusion

    DEFF Research Database (Denmark)

    Vannahme, Christoph; Dufva, Martin; Kristensen, Anders

    2014-01-01

    distributed feedback (DFB) dye laser sensor for real-time label-free imaging without any moving parts enabling a frame rate of 12 Hz is presented. The presence of molecules on the laser surface results in a wavelength shift which is used as sensor signal. The unique DFB laser structure comprises several areas...... molecules in water....

  17. Three native somatostatin isoforms differentially affect membrane voltage-sensitive ion currents in goldfish somatotrophs.

    Science.gov (United States)

    Yu, Y; Ali, D W; Chang, J P

    2011-01-01

    Message encoding for three isoforms of somatostatin (SS) peptides, SS-14, goldfish brain (gb)SS-28 and [Pro²]SS-14, are expressed in goldfish hypothalamus and pituitary tissues. All three native goldfish SSs are active in reducing basal and stimulated growth hormone (GH) responses in cultured goldfish pituitary cells, although with different potencies and efficacies. In the present study, we examined the effects of these three endogenous SSs on electrophysiological properties of goldfish somatotrophs and their physiological relevance. Voltage-sensitive K+ , Ca²+ and Na+ channels in identified goldfish somatotrophs in primary culture were isolated using whole-cell, amphotericin B-perforated patch-clamp techniques. None of the three SSs affected Na+ currents but all three SSs increased maximal K+ current magnitude, with SS-14 being the most effective. [Pro²]SS14 did not affect Ba²+ currents through voltage-sensitive Ca²+ channels but SS14 decreased the magnitude of early and late Ba²+ currents, whereas gbSS-28 reduced that of the late Ba²+ current. Under current-clamp conditions, SS14 and gbSS28 attenuated evoked action potential magnitudes by 34% and 18%, respectively, although [Pro²]SS14 had no effects. However, all three SSs decreased basal intracellular Ca²+ levels ([Ca²+ ](i)) and suppressed basal GH release. These data suggest that, although the ability of SS-14 and gbSS-28 to decrease basal [Ca²+](i) and GH release can be explained, at least in part, by their attenuating effects on cell excitability and current flow through voltage-sensitive Ca²+ channels, [Pro²]SS14-induced reduction in GH responses and [Ca²+](i) cannot be explained by changes in Ca²+ channel properties. © 2010 The Authors. Journal of Neuroendocrinology © 2010 Blackwell Publishing Ltd.

  18. Spectral Imaging of Multi-Color Chromogenic Dyes in Pathological Specimens

    Directory of Open Access Journals (Sweden)

    Merryn V. E. Macville

    2001-01-01

    Full Text Available We have investigated the use of spectral imaging for multi‐color analysis of permanent cytochemical dyes and enzyme precipitates on cytopathological specimens. Spectral imaging is based on Fourier‐transform spectroscopy and digital imaging. A pixel‐by‐pixel spectrum‐based color classification is presented of single‐, double‐, and triple‐color in situ hybridization for centromeric probes in T24 bladder cancer cells, and immunocytochemical staining of nuclear antigens Ki‐67 and TP53 in paraffin‐embedded cervical brush material (AgarCyto. The results demonstrate that spectral imaging unambiguously identifies three chromogenic dyes in a single bright‐field microscopic specimen. Serial microscopic fields from the same specimen can be analyzed using a spectral reference library. We conclude that spectral imaging of multi‐color chromogenic dyes is a reliable and robust method for pixel color recognition and classification. Our data further indicate that the use of spectral imaging (a may increase the number of parameters studied simultaneously in pathological diagnosis, (b may provide quantitative data (such as positive labeling indices more accurately, and (c may solve segmentation problems currently faced in automated screening of cell‐ and tissue specimens. Figures on http://www.esacp.org/acp/2001/22‐3/macville.htm.

  19. Micromolar-Affinity Benzodiazepine Receptors Regulate Voltage-Sensitive Calcium Channels in Nerve Terminal Preparations

    Science.gov (United States)

    Taft, William C.; Delorenzo, Robert J.

    1984-05-01

    Benzodiazepines in micromolar concentrations significantly inhibit depolarization-sensitive Ca2+ uptake in intact nerve-terminal preparations. Benzodiazepine inhibition of Ca2+ uptake is concentration dependent and stereospecific. Micromolar-affinity benzodiazepine receptors have been identified and characterized in brain membrane and shown to be distinct from nanomolar-affinity benzodiazepine receptors. Evidence is presented that micromolar, and not nanomolar, benzodiazepine binding sites mediate benzodiazepine inhibition of Ca2+ uptake. Irreversible binding to micromolar benzodiazepine binding sites also irreversibly blocked depolarization-dependent Ca2+ uptake in synaptosomes, indicating that these compounds may represent a useful marker for identifying the molecular components of Ca2+ channels in brain. Characterization of benzodiazepine inhibition of Ca2+ uptake demonstrates that these drugs function as Ca2+ channel antagonists, because benzodiazepines effectively blocked voltage-sensitive Ca2+ uptake inhibited by Mn2+, Co2+, verapamil, nitrendipine, and nimodipine. These results indicate that micromolar benzodiazepine binding sites regulate voltage-sensitive Ca2+ channels in brain membrane and suggest that some of the neuronal stabilizing effects of micromolar benzodiazepine receptors may be mediated by the regulation of Ca2+ conductance.

  20. Dyes removal using activated carbon from palm oil waste with digital image colorimetry quantification

    Science.gov (United States)

    Firdaus, M. Lutfi; Puspita, Melfi; Alwi, Wiwit; Ghufira, Nurhamidah, Elvia, Rina

    2017-11-01

    In the present study, activated carbon prepared from palm oil husk was used as adsorbent to remove synthetic dyes of Reactive Red 120 (RR) and Direct Green 26 (DG) from aqueous solution. The effects of solution pH, contact time, adsorbent weight, dyes concentration, and temperature on adsorption were evaluated based on batch experiments along with determination of the adsorption isotherms, kinetics, and thermodynamics parameters. Visible spectrophotometry was used for the quantification of dyes concentration, in conjunction with digital image colorimetry as a novel quantification method. Compared to visible spectrophotometry, the results of digital image colorimetry were accurate. In addition, improved sensitivity was achieved using this new colorimetry method. At equilibrium, dyes adsorption onto activated carbon followed Freundlich model, with adsorption capacities for RR and DG were 32 and 27 mg/g, respectively. The adsorption kinetics study showed a pseudo-second-order model with thermodynamic parameters of ΔG°, ΔH°, and ΔS° were -1.8 to -3.8 kJ/mol, -13.5 to -24.38 kJ/mol, and 0.001 J/mol, respectively. Therefore, the process of adsorption was exothermic and spontaneous with an increase in the disorder or entropy of the system.

  1. Quantification of dye-mediated photodamage during single-molecule DNA imaging.

    Science.gov (United States)

    Tycon, Michael A; Dial, Catherine F; Faison, Keia; Melvin, Whitney; Fecko, Christopher J

    2012-07-01

    Single-molecule fluorescence imaging of DNA-binding proteins has enabled detailed investigations of their interactions. However, the intercalating dyes used to visually locate DNA molecules have the undesirable effect of photochemically damaging the DNA through radical intermediaries. Unfortunately, this damage occurs as single-strand breaks (SSBs), which are visually undetectable but can heavily influence protein behavior. We investigated the formation of SSBs on DNA molecules by the dye YOYO-1 using complementary single-molecule imaging and gel electrophoresis-based damage assays. The single-molecule assay imaged hydrodynamically elongated lambda DNA, enabling the real-time detection of double-strand breaks (DSBs). The gel assay, which used supercoiled plasmid DNA, was sensitive to both SSBs and DSBs. This enabled the quantification of SSBs that precede DSB formation. Using the parameters determined from the gel damage assay, we applied a model of stochastic DNA damage to the time-resolved DNA breakage data, extracting the rates of single-strand breakage at two dye staining ratios and measuring the damage reduction from the radical scavengers ascorbic acid and β-mercaptoethanol. These results enable the estimation of the number of SSBs that occur during imaging and are scalable over a wide range of laser intensities used in fluorescence microscopy. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Superresolution imaging of single DNA molecules using stochastic photoblinking of minor groove and intercalating dyes.

    Science.gov (United States)

    Miller, Helen; Zhou, Zhaokun; Wollman, Adam J M; Leake, Mark C

    2015-10-15

    As proof-of-principle for generating superresolution structural information from DNA we applied a method of localization microscopy utilizing photoblinking comparing intercalating dye YOYO-1 against minor groove binding dye SYTO-13, using a bespoke multicolor single-molecule fluorescence microscope. We used a full-length ∼49 kbp λ DNA construct possessing oligo inserts at either terminus allowing conjugation of digoxigenin and biotin at opposite ends for tethering to a glass coverslip surface and paramagnetic microsphere respectively. We observed stochastic DNA-bound dye photoactivity consistent with dye photoblinking as opposed to binding/unbinding events, evidenced through both discrete simulations and continuum kinetics analysis. We analyzed dye photoblinking images of immobilized DNA molecules using superresolution reconstruction software from two existing packages, rainSTORM and QuickPALM, and compared the results against our own novel home-written software called ADEMS code. ADEMS code generated lateral localization precision values of 30-40 nm and 60-70 nm for YOYO-1 and SYTO-13 respectively at video-rate sampling, similar to rainSTORM, running more slowly than rainSTORM and QuickPALM algorithms but having a complementary capability over both in generating automated centroid distribution and cluster analyses. Our imaging system allows us to observe dynamic topological changes to single molecules of DNA in real-time, such as rapid molecular snapping events. This will facilitate visualization of fluorescently-labeled DNA molecules conjugated to a magnetic bead in future experiments involving newly developed magneto-optical tweezers combined with superresolution microscopy. Copyright © 2015. Published by Elsevier Inc.

  3. Synthesis, surface modification and biological imaging of aggregation-induced emission (AIE) dye doped silica nanoparticles

    Science.gov (United States)

    Mao, Liucheng; Liu, Meiying; Xu, Dazhuang; Wan, Qing; Huang, Qiang; Jiang, Ruming; Shi, Yingge; Deng, Fengjie; Zhang, Xiaoyong; Wei, Yen

    2017-05-01

    Fluorescent silica nanoparticles (FSNPs) have been extensively investigated for various biomedical applications in recently years. However, the aggregation of organic dyes in silica nanoparticles also leads the significant fluorescence quenching owing to the aggregation caused quenching effects of organic dyes. Herein, we developed a rather facile strategy to fabricate FSNPs with desirable fluorescent properties through non-covalent incorporation of fluorophores with aggregation-induced emission (AIE) feature into silica nanoparticles, which were subsequently modified with functional polymers. The resultant FSNPs polymer nanocomposites (named as FSNPs-poly(IA-co-PEGMA)) exhibited uniform spherical morphology, high water dispersiity, and bright red fluorescence. Cytotoxicity results indicate that FSNPs-poly(IA-co-PEGMA) possess excellent biocompatibility. Cell uptake behavior suggests FSNPs-poly(IA-co-PEGMA) are of great potential for biological imaging applications. Taken together, we have reported a facile method for the fabrication of FSNPs through non-covalent encapsulation using an AIE-active dye. These FSNPs can be further functionalized with functional polymers through ring-opening reaction and the resultant FSNPs-poly(IA-co-PEGMA) showed great potential for biological imaging. More importantly, we believe that many other functional components could also be integrated into these FSNPs through the facile ring-opening reaction. Therefore, this method should be a facile and general tool for fabrication of polymer functionalized AIE-active FSNPs.

  4. High frame rate multi-resonance imaging refractometry with distributed feedback dye laser sensor

    DEFF Research Database (Denmark)

    Vannahme, Christoph; Dufva, Martin; Kristensen, Anders

    2015-01-01

    High frame rate and highly sensitive imaging of refractive index changes on a surface is very promising for studying the dynamics of dissolution, mixing and biological processes without the need for labeling. Here, a highly sensitive distributed feedback (DFB) dye laser sensor for high frame rate...... by analyzing laser light from all areas in parallel with an imaging spectrometer. With this multi-resonance imaging refractometry method, the spatial position in one direction is identified from the horizontal, i.e., spectral position of the multiple laser lines which is obtained from the spectrometer charged...... coupled device (CCD) array. The orthogonal spatial position is obtained from the vertical spatial position on the spectrometer CCD array as in established spatially resolved spectroscopy. Here, the imaging technique is demonstrated by monitoring the motion of small sucrose molecules upon dissolution...

  5. New Conotoxin SO-3 Targeting N-type Voltage-Sensitive Calcium Channels

    Directory of Open Access Journals (Sweden)

    Lei Wen

    2006-04-01

    Full Text Available Selective blockers of the N-type voltage-sensitive calcium (CaV channels are useful in the management of severe chronic pain. Here, the structure and function characteristics of a novel N-type CaV channel blocker, SO-3, are reviewed. SO-3 is a 25-amino acid conopeptide originally derived from the venom of Conus striatus, and contains the same 4-loop, 6-cysteine framework (C-C-CC-C-C as O-superfamily conotoxins. The synthetic SO-3 has high analgesic activity similar to ω-conotoxin MVIIA (MVIIA, a selective N-type CaV channel blocker approved in the USA and Europe for the alleviation of persistent pain states. In electrophysiological studies, SO-3 shows more selectivity towards the N-type CaV channels than MVIIA. The dissimilarity between SO-3 and MVIIA in the primary and tertiary structures is further discussed in an attempt to illustrate the difference in selectivity of SO-3 and MVIIA towards N-type CaV channels.

  6. Combining aminocyanine dyes with polyamide dendrons: a promising strategy for imaging in the near-infrared region.

    Science.gov (United States)

    Ornelas, Cátia; Lodescar, Rachelle; Durandin, Alexander; Canary, James W; Pennell, Ryan; Liebes, Leonard F; Weck, Marcus

    2011-03-21

    Cyanine dyes are known for their fluorescence in the near-IR (NIR) region, which is desirable for biological applications. We report the synthesis of a series of aminocyanine dyes containing terminal functional groups such as acid, azide, and cyclooctyne groups for further functionalization through, for example, click chemistry. These aminocyanine dyes can be attached to polyfunctional dendrons by copper-catalyzed azide alkyne cycloaddition (CuAAC), strain-promoted azide alkyne cycloaddition (SPAAC), peptide coupling, or direct S(NR)1 reactions. The resulting dendron-dye conjugates were obtained in high yields and displayed high chemical stability and photostability. The optical properties of the new compounds were studied by UV/Vis and fluorescence spectroscopy. All compounds show large Stokes shifts and strong fluorescence in the NIR region with high quantum yields, which are optimal properties for in vivo optical imaging. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Resolution of multiple GFP color variants and dyes using two-photon microscopy and imaging spectroscopy

    Science.gov (United States)

    Lansford, Rusty; Bearman, Gregory H.; Fraser, Scott E.

    2001-07-01

    The imaging of living cells and tissues using laser-scanning microscopy is offering dramatic insights into the spatial and temporal controls of biological processes. The availability of genetically encoded labels such as green fluorescent protein (GFP) offers unique opportunities by which to trace cell movements, cell signaling or gene expression dynamically in developing embryos. Two-photon laser scanning microscopy (TPLSM) is ideally suited to imaging cells in vivo due to its deeper tissue penetration and reduced phototoxicity; however, in TPLSM the excitation and emission spectra of GFP and its color variants [e.g., CyanFP (CFP); yellowFP (YFP)] are insufficiently distinct to be uniquely imaged by conventional means. To surmount such difficulties, we have combined the technologies of TPLSM and imaging spectroscopy to unambiguously identify CFP, GFP, YFP, and redFP (RFP) as well as conventional dyes, and have tested the approach in cell lines. In our approach, a liquid crystal tunable filter was used to collect the emission spectrum of each pixel within the TPLSM image. Based on the fluorescent emission spectra, supervised classification and linear unmixing analysis algorithms were used to identify the nature and relative amounts of the fluorescent proteins expressed in the cells. In a most extreme case, we have used the approach to separate GFP and fluorescein, separated by only 7 nm, and appear somewhat indistinguishable by conventional techniques. This approach offers the needed ability to concurrently image multiple colored, spectrally overlapping marker proteins within living cells.

  8. Synthesis and evaluation of carbocyanine dyes as PRMT inhibitors and imaging agents.

    Science.gov (United States)

    Sinha, Sarmistha Halder; Owens, Eric A; Feng, You; Yang, Yutao; Xie, Yan; Tu, Yaping; Henary, Maged; Zheng, Yujun George

    2012-08-01

    Protein arginine methylation regulates multiple biological processes. Deregulation of protein arginine methyltransferase (PRMT) activities has been observed in many disease phenotypes. Small molecule probes that target PRMTs with strong affinity and selectivity can be used as valuable tools to dissect biological mechanisms of arginine methylation and establish the role of PRMT proteins in a disease process. In this work, we report synthesis and evaluation of a class of carbocyanine compounds containing indolium, benz[e]indolium or benz[c,d]indolium heterocyclic moieties that bind to the predominant arginine methyltransferase PRMT1 and inhibit its methyltransferase activity at low micromolar potencies. In particular, the developed molecules have long wavelength colorimetric and fluorometric photoactivities, which can be used for optical and near-infrared fluorescence imaging in cells or biological tissues. Together, these new chemical probes have potential application in PRMT studies both as enzyme inhibitors and as fluorescent dyes for microscope imaging. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  9. Simultaneous determination of some common food dyes in commercial products by digital image analysis

    Directory of Open Access Journals (Sweden)

    Mohammad-Hossein Sorouraddin

    2015-09-01

    Full Text Available A simple and relatively fast image-analysis method using digital images, obtained with a flatbed scanner, has been described. The method was used for the simultaneous determination of four common food dyes, namely, carmoisine, brilliant blue, sunset yellow, and quinoline yellow, in binary mixtures in commercial products without a need for any prior separation steps. The results obtained were validated against a standard high-performance liquid chromatography method and a good agreement was obtained. The parameters affecting the experimental results were optimized. Under the optimal conditions, the method provided acceptable linear ranges (20–250 mg/L with correlation coefficients higher than 0.998, suitable precision (relative standard deviation ≤ 4.5%, and limits of detection between 4.82 and 8.05 mg/L.

  10. PLGA nanoparticles from nano-emulsion templating as imaging agents: Versatile technology to obtain nanoparticles loaded with fluorescent dyes.

    Science.gov (United States)

    Fornaguera, C; Feiner-Gracia, N; Calderó, G; García-Celma, M J; Solans, C

    2016-11-01

    The interest in polymeric nanoparticles as imaging systems for biomedical applications has increased notably in the last decades. In this work, PLGA nanoparticles, prepared from nano-emulsion templating, have been used to prepare novel fluorescent imaging agents. Two model fluorescent dyes were chosen and dissolved in the oil phase of the nano-emulsions together with PLGA. Nano-emulsions were prepared by the phase inversion composition (PIC) low-energy method. Fluorescent dye-loaded nanoparticles were obtained by solvent evaporation of nano-emulsion templates. PLGA nanoparticles loaded with the fluorescent dyes showed hydrodynamic radii lower than 40nm; markedly lower than those reported in previous studies. The small nanoparticle size was attributed to the nano-emulsification strategy used. PLGA nanoparticles showed negative surface charge and enough stability to be used for biomedical imaging purposes. Encapsulation efficiencies were higher than 99%, which was also attributed to the nano-emulsification approach as well as to the low solubility of the dyes in the aqueous component. Release kinetics of both fluorescent dyes from the nanoparticle dispersions was pH-independent and sustained. These results indicate that the dyes could remain encapsulated enough time to reach any organ and that the decrease of the pH produced during cell internalization by the endocytic route would not affect their release. Therefore, it can be assumed that these nanoparticles are appropriate as systemic imaging agents. In addition, in vitro toxicity tests showed that nanoparticles are non-cytotoxic. Consequently, it can be concluded that the preparation of PLGA nanoparticles from nano-emulsion templating represents a very versatile technology that enables obtaining biocompatible, biodegradable and safe imaging agents suitable for biomedical purposes. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Estrogen receptor-targeted optical imaging of breast cancer cells with near-infrared fluorescent dye

    Science.gov (United States)

    Jose, Iven; Deodhar, Kodand; Chiplunkar, Shuba V.; Patkar, Meena

    2010-02-01

    Molecular imaging provides the in vivo characterization of cellular molecular events involved in normal and pathologic processes. With the advent of optical molecular imaging, specific molecules, proteins and genes may be tagged with a luminescent reporter and visualized in small animals. This powerful new tool has pushed in vivo optical imaging to the forefront as it allows for direct determination of drug bio-distribution and uptake kinetics as well as an indicator of biochemical activity and drug efficacy. Although optical imaging encompasses diverse techniques and makes use of various wavelengths of light, a great deal of excitement in molecular research lies in the use of tomographic and fluorescence techniques to image living tissues with near-infrared (NIR) light. Nonionizing, noninvasive near-infrared optical imaging has great potential to become promising alternative for breast cancer detection. Fluorescence spectroscopy studies of human tissue suggest that a variety of lesions show distinct fluorescence spectra compared to those of normal tissue. It has also been shown that exogenous dyes exhibit selective uptake in neoplastic lesions and may offer the best contrast for optical imaging. Use of exogenous agents would provide fluorescent markers, which could serve to detect embedded tumors in the breast. In particular, the ability to monitor the fluorescent yield and lifetime may also enable biochemical specificity if the fluorophore is sensitive to a specific metabolite, such as oxygen. As a first step, we have synthesized and characterized one such NIR fluorescent dye conjugate, which could potentially be used to detect estrogen receptors (ER)[2] . The conjugate was synthesized by ester formation between 17-β estradiol and a hydrophilic derivative of indocyanine green (ICG) cyanine dye, bis-1, 1-(4-sulfobutyl) indotricarbocyanine-5- carboxylic acid, sodium salt. The ester formed was found to have an extra binding ability with the receptor cites as

  12. Quantification of pressure sensitive adhesive, residual ink, and other colored process contaminants using dye and color image analysis

    Science.gov (United States)

    Roy R. Rosenberger; Carl J. Houtman

    2000-01-01

    The USPS Image Analysis (IA) protocol recommends the use of hydrophobic dyes to develop contrast between pressure sensitive adhesive (PSA) particles and cellulosic fibers before using a dirt counter to detect all contaminants that have contrast with the handsheet background. Unless the sample contains no contaminants other than those of interest, two measurement steps...

  13. Magnified endoscopic observation of small depressed gastric lesions using linked color imaging with indigo carmine dye.

    Science.gov (United States)

    Kitagawa, Yoshiyasu; Hara, Taro; Ikebe, Dai; Nankinzan, Rino; Takashiro, Hideyuki; Kobayashi, Ryosuke; Nakamura, Kazuyoshi; Yamaguchi, Taketo; Suzuki, Takuto

    2018-02-01

     Magnifying linked color imaging with indigo carmine dye (M-Chromo-LCI) enables sterically enhanced and color image-magnified observation of the superficial gastric mucosa. This study investigated the usefulness of M-Chromo-LCI for the differential diagnosis of gastric lesions.  100 consecutive small depressed lesions were examined with conventional white-light imaging (C-WLI), magnifying blue-laser imaging (M-BLI), and M-Chromo-LCI. Endoscopic images were reviewed by three experts and three non-experts. Diagnostic accuracy and interobserver agreement were compared among the modalities.  For experts, M-BLI showed a significantly higher diagnostic accuracy than C-WLI (82.7 % vs. 67.0 %; P < 0.001). The diagnostic accuracy of M-Chromo-LCI was not different from M-BLI (87.7 % vs. 82.7 %; P = 0.31). For non-experts, M-BLI showed a significantly higher diagnostic accuracy than C-WLI (69.3 % vs. 52.3 %; P < 0.001). M-Chromo-LCI additionally showed a significantly higher diagnostic accuracy than M-BLI (79.7 % vs. 69.3 %; P = 0.005). M-Chromo-LCI had the highest interobserver agreement for each group. M-Chromo-LCI is expected to become a useful modality for the accurate diagnosis of gastric lesions. © Georg Thieme Verlag KG Stuttgart · New York.

  14. FACILITATING IMAGE-ANALYSIS OF GLYCOLMETHACRYLATE EMBEDDED TISSUES WITH TISSUE-SELECTIVE AND RESIN-SELECTIVE DYES, CHOSEN BY A NUMERICAL STRUCTURE-STAINING RELATIONSHIP MODEL

    NARCIS (Netherlands)

    GERRITS, PO; HOROBIN, RW; STOKROOS, [No Value

    A method facilitating recording of macroscopic images from glycolmethacrylate (GMA) embedded tissues and tissue-free sections is described. This method used dyes that selectively stain only tissue, only resin, or both, but in contrasting colors. The dyes were selected on the basis of simple

  15. Evans blue dye-enhanced imaging of the brain microvessels using spectral focusing coherent anti-Stokes Raman scattering microscopy.

    Directory of Open Access Journals (Sweden)

    Bo-Ram Lee

    Full Text Available We performed dye-enhanced imaging of mouse brain microvessels using spectral focusing coherent anti-Stokes Raman scattering (SF-CARS microscopy. The resonant signals from C-H stretching in forward CARS usually show high background intensity in tissues, which makes CARS imaging of microvessels difficult. In this study, epi-detection of back-scattered SF-CARS signals showed a negligible background, but the overall intensity of resonant CARS signals was too low to observe the network of brain microvessels. Therefore, Evans blue (EB dye was used as contrasting agent to enhance the back-scattered SF-CARS signals. Breakdown of brain microvessels by inducing hemorrhage in a mouse was clearly visualized using backward SF-CARS signals, following intravenous injection of EB. The improved visualization of brain microvessels with EB enhanced the sensitivity of SF-CARS, detecting not only the blood vessels themselves but their integrity as well in the brain vasculature.

  16. Hydrophobic cyanine dye-doped micelles for optical in vivo imaging of plasma leakage and vascular disruption

    Science.gov (United States)

    Botz, Bálint; Bölcskei, Kata; Kemény, Ágnes; Sándor, Zoltán; Tékus, Valéria; Sétáló, György, Jr.; Csepregi, Janka; Mócsai, Attila; Pintér, Erika; Kollár, László; Helyes, Zsuzsanna

    2015-01-01

    Vascular leakage is an important feature of various disease conditions. In vivo optical imaging provides a great opportunity for the evaluation of this phenomenon. In the present study, we focus on the development and validation of a near-infrared (NIR) imaging formula to allow reliable, cost-efficient evaluation of vascular leakage in diverse species using the existing small-animal fluorescence imaging technology. IR-676, a moderately hydrophobic NIR cyanine dye, was doped into self-assembling aqueous micelles using a widely employed and safe nonionic emulsifier (Kolliphor HS 15), and was tested in several acute and chronic inflammatory disease models in both mice and rats. The imaging formula is stable and exerts no acute toxic effects in vitro. It accumulated specifically in the inflamed regions in all models, which could be demonstrated by both conventional epifluorescence imaging, and fluorescence tomography both as a standalone technique and also by merging it with computed tomography scans. Ex vivo verification of dye accumulation by confocal fluorescence microscopy was also possible. The present formula allows sensitive and specific detection of inflammatory plasma leakage in diverse models. Its potential for imaging larger animals was also demonstrated. IR-676-doped micelles offer an excellent opportunity to image inflammatory vascular leakage in various models and species.

  17. Plasmonic enhancement of cyanine dyes for near-infrared light-triggered photodynamic/photothermal therapy and fluorescent imaging

    Science.gov (United States)

    Lu, Mindan; Kang, Ning; Chen, Chuan; Yang, Liuqing; Li, Yang; Hong, Minghui; Luo, Xiangang; Ren, Lei; Wang, Xiumin

    2017-11-01

    Near-infrared (NIR) triggered cyanine dyes have attracted considerable attention in multimodal tumor theranostics. However, NIR cyanine dyes used in tumor treatment often suffer from low fluorescence intensity and weak singlet oxygen generation efficiency, resulting in inadequate diagnostic and therapy efficacy for tumors. It is still a great challenge to improve both the photodynamic therapy (PDT) and fluorescent imaging (FLI) efficacy of cyanine dyes in tumor applications. Herein, a novel multifunctional nanoagent AuNRs@SiO2-IR795 was developed to realize the integrated photothermal/photodynamic therapy (PTT/PDT) and FLI at a very low dosage of IR795 (0.4 μM) based on metal-enhanced fluorescence (MEF) effects. In our design, both the fluorescence intensity and reactive oxygen species of AuNRs@SiO2-IR795 nanocomposites were significantly enhanced up to 51.7 and 6.3 folds compared with free IR795, owing to the localized surface plasmon resonance band of AuNRs overlapping with the absorption or fluorescence emission band of the IR795 dye. Under NIR laser irradiation, the cancer cell inhibition efficiency in vitro with synergetic PDT/PTT was up to 82.3%, compared with 10.3% for free IR795. Moreover, the enhanced fluorescence intensity of our designed nanocomposites was helpful to track their behavior in tumor cells. Therefore, our designed nanoagents highlight the applications of multimodal diagnostics and therapy in tumors based on MEF.

  18. Near-infrared fluorescent aza-BODIPY dye-loaded biodegradable polymeric nanoparticles for optical cancer imaging

    Energy Technology Data Exchange (ETDEWEB)

    Hamon, Casey L.; Dorsey, Christopher L. [Texas State University, Department of Chemistry and Biochemistry (United States); Özel, Tuğba [Texas State University, Materials Science, Engineering, and Commercialization Program (United States); Barnes, Eugenia M.; Hudnall, Todd W.; Betancourt, Tania, E-mail: tb26@txstate.edu [Texas State University, Department of Chemistry and Biochemistry (United States)

    2016-07-15

    Nanoparticles are being readily investigated as carriers for the delivery of imaging and therapeutic agents for the detection, monitoring, and treatment of cancer and other diseases. In the present work, the preparation of biodegradable polymeric nanoparticles loaded with a near-infrared fluorescent aza-boron dipyrromethene (NIR-BODIPY) derivative, and their use as contrast agents for optical imaging in cancer are described. Nanoparticles were prepared by nanoprecipitation of amphiphilic block copolymers of poly(lactic acid) and poly(ethylene glycol). The size, morphology, dye loading, spectral properties, quantum yield, cytocompatibility, and in vitro NIR imaging potential of the nanoparticles in breast and ovarian cancer cells were evaluated. Spherical nanoparticles of 30–70 nm in diameter were loaded with 0.73 w/w% BODIPY derivative. At this loading, the dye presented a fluorescence quantum yield in the same order of magnitude as in solution. Nanoparticle suspensions at concentrations up to 580 μg/mL were cytocompatible to breast (MDA-MB-231) and ovarian (SKOV-3 and Caov-3) cancer cells after a four-hour incubation period. Fluorescence microscopy images demonstrated the ability of the nanoparticles to act as imaging agents in all three cell lines in as little as 1 hour. The results shown indicate the potential of these NIR-BODIPY-loaded nanoparticles as contrast agents for near-infrared optical imaging in cancer.Graphical abstract.

  19. Dye Tracer Technique and Color Image Analysis For Describing Saturation State and 3d Axi-symmetrical Flow Pattern

    Science.gov (United States)

    Abriak, N. E.; Gandola, F.; Haverkamp, R.

    Dye tracer techniques have been widely used for visualising water flow pattern in soils and particularly, for determining the volumetric water content in a one dimensional and two dimensional laboratory experiments. The present study deals a 3 dimensional laboratory experiment (axi-symmetrical condition) using color visualisation technique and the image analysis technique for determining the spatial distribution of the water content. The infiltration of a dye (fluorescein) mixed with water is achieved under ax- isymmetrical condition in a Plexiglas tank (50t'50t'60cm) filled with a low saturated sand. Both infiltration and drainage processes are visualised under blue light condi- tion and recorded on videotape. The image analysis technique used for determining the saturation state is based on the use of a limited colors palette which allows to quan- tify the evolution of the saturation state in the sand. Simultaneously, nine tensiometers connected to a data acquisition system, are used to determine the negative water pres- sure in the sand. The measurement of the succion values confirms the existence of a second water wetting front (after the dye flow) due to the initial mobile water content in the sand.

  20. Electromagnetic fields (UHF) increase voltage sensitivity of membrane ion channels; possible indication of cell phone effect on living cells.

    Science.gov (United States)

    Ketabi, N; Mobasheri, H; Faraji-Dana, R

    2015-03-01

    The effects of ultra high frequency (UHF) nonionizing electromagnetic fields (EMF) on the channel activities of nanopore forming protein, OmpF porin, were investigated. The voltage clamp technique was used to study the single channel activity of the pore in an artificial bilayer in the presence and absence of the electromagnetic fields at 910 to 990 MHz in real time. Channel activity patterns were used to address the effect of EMF on the dynamic, arrangement and dielectric properties of water molecules, as well as on the hydration state and arrangements of side chains lining the channel barrel. Based on the varied voltage sensitivity of the channel at different temperatures in the presence and absence of EMF, the amount of energy transferred to nano-environments of accessible groups was estimated to address the possible thermal effects of EMF. Our results show that the effects of EMF on channel activities are frequency dependent, with a maximum effect at 930 MHz. The frequency of channel gating and the voltage sensitivity is increased when the channel is exposed to EMF, while its conductance remains unchanged at all frequencies applied. We have not identified any changes in the capacitance and permeability of membrane in the presence of EMF. The effect of the EMF irradiated by cell phones is measured by Specific Absorption Rate (SAR) in artificial model of human head, Phantom. Thus, current approach applied to biological molecules and electrolytes might be considered as complement to evaluate safety of irradiating sources on biological matter at molecular level.

  1. AHR-16303B, a novel antagonist of 5-HT2 receptors and voltage-sensitive calcium channels

    Energy Technology Data Exchange (ETDEWEB)

    Barrett, R.J.; Appell, K.C.; Kilpatrick, B.F.; Proakis, A.G.; Nolan, J.C.; Walsh, D.A. (A. H. Robins Research Labs., Richmond, VA (USA))

    1991-01-01

    In vivo and in vitro methods were used to characterize AHR-16303B, a novel compound with antagonistic action at 5-HT2 receptors and voltage-sensitive calcium channels. The 5-HT2 receptor-antagonistic properties of AHR-16303B were demonstrated by inhibition of (a) (3H)ketanserin binding to rat cerebral cortical membranes (IC50 = 165 nM); (b) 5-hydroxytryptamine (5-HT)-induced foot edema in rats (minimum effective dose, (MED) = 0.32 mg/kg orally, p.o.); (c) 5-HT-induced vasopressor responses in spontaneously hypertensive rats (SHR) (ID50 = 0.18 mg/kg intravenously (i.v.), 1.8 mg/kg p.o.), (d) 5-HT-induced antidiuresis in rats (MED = 1 mg/kg p.o.), and (e) platelet aggregation induced by 5-HT + ADP (IC50 = 1.5 mM). The calcium antagonist properties of AHR-16303B were demonstrated by inhibition of (a) (3H)nimodipine binding to voltage-sensitive calcium channels on rabbit skeletal muscle membranes (IC50 = 15 nM), (b) KCl-stimulated calcium flux into cultured PC12 cells (IC50 = 81 nM), and (c) CaCl2-induced contractions of rabbit thoracic aortic strips (pA2 = 8.84). AHR-16303B had little or no effect on binding of radioligands to dopamine2 (DA2) alpha 1, alpha 2, H1, 5-HT1 alpha, beta 2, muscarinic M1, or sigma opioid receptors; had no effect on 5-HT3 receptor-mediated vagal bradycardia; and had only minor negative inotropic, chronotropic, and dromotropic effects on isolated guinea pig atria. In conscious SHR, 30 mg/kg p.o. AHR-16303B completely prevented the vasopressor responses to i.v. 5-HT, and decreased blood pressure (BP) by 24% 3 h after dosing.

  2. Evaluation of ¹⁸F-labeled BODIPY dye as potential PET agents for myocardial perfusion imaging.

    Science.gov (United States)

    Liu, Shuanglong; Li, Dan; Shan, Hong; Gabbaï, Francois P; Li, Zibo; Conti, Peter S

    2014-01-01

    Despite the great potential of positron emission tomography/computed tomography (PET/CT) in cardiovascular disease imaging, one of the major limitations is the availability of PET probes with desirable half-lives and reasonable cost. In this report, we hypothesized that lipophilic cationic BODIPY dye could be selectively accumulated in cardiac muscle, possibly for the development of novel PET myocardial perfusion imaging (MPI) probes. A (18)F-labeled BODIPY dye ([(18)F]1) was synthesized efficiently through a fluoride exchange reaction catalyzed by the Lewis acid tin chloride (SnCl₄). The compound was first evaluated by a cellular uptake assay in vitro, followed by biodistribution and microPET imaging studies in vivo. [(18)F]1 was obtained in more than 90% labeling yield, with >98% radiochemical purity. The HEK-293 cellular uptake assay showed that the preferential uptake of [(18)F]1 could be related to the cell membrane potential. The biodistribution data demonstrated high levels of [(18)F]1 accumulation in the heart. In the biodistribution study in mice, the radioactivity uptake in the heart, blood, liver and lung was 3.01 ± 0.44, 0.39 ± 0.09, 0.69 ± 0.07, 1.71 ± 0.27%ID/g, respectively, at 3h post-injection (p.i.). The heart-to-lung and heart-to-liver ratios are 1.76 ± 0.14 and 4.37 ± 0.51 at 3h p.i., respectively. Volume-of-interest analysis of the microPET images correlated well with the biodistribution studies in mice. The heart was clearly visualized in normal rats, with 0.72 ± 0.18, 0.69 ± 0.18, 0.67 ± 0.20 and 0.59 ± 0.17%ID/g uptake at 0.5, 1, 2 and 4h p.i., respectively. (18)F-labeled BODIPY dye showed good heart uptake and heart-to-blood and heart-to-lung contrast. A (18)F-labeled BODIPY dyes may represent a new category of cationic PET agents for myocardial perfusion imaging. © 2013.

  3. Hole Burning Imaging Studies of Cancerous and Analogous Normal Ovarian Tissues Utilizing Organelle Specific Dyes

    Energy Technology Data Exchange (ETDEWEB)

    Matsuzaki, Satoshi [Iowa State Univ., Ames, IA (United States)

    2004-01-01

    Presented in this dissertation is the successful demonstration that nonphotochemical hole burning (NPWB) imaging can be used to study in vitro tissue cellular systems for discerning differences in cellular ultrastructures due to cancer development. This has been accomplished with the surgically removed cancerous ovarian and analogous normal peritoneal tissues from the same patient and the application of a fluorescent mitochondrion specific dye, Molecular Probe MitoFluor Far Red 680 (MF680), commonly known as rhodamine 800, that has been proven to exhibit efficient NPHB. From the results presented in Chapters 4 and 5 , and Appendix B, the following conclusions were made: (1) fluorescence excitation spectra of MF680 and confocal microscopy images of thin sliced tissues incubated with MF680 confirm the site-specificity of the probe molecules in the cellular systems. (2) Tunneling parameters, {lambda}{sub 0} and σΛ, as well as the standard hole burning parameters (namely, γ and S), have been determined for the tissue samples by hole growth kinetics (HGK) analyses. Unlike the preliminary cultured cell studies, these parameters have not shown the ability to distinguish tissue cellular matrices surrounding the chromophores. (3) Effects of an external electric (Stark) field on the nonphotochemical holes have been used to determine the changes in permanent dipole moment (fΔμ) for MF680 in tissue samples when burn laser polarization is parallel to the Stark field. Differences are detected between fΔμs in the two tissue samples, with the cancerous tissue exhibiting a more pronounced change (1.35-fold increase) in permanent dipole moment change relative to the normal analogs. It is speculated that the difference may be related to differences in mitochondrial membrane potentials in these tissue samples. (4) In the HGK mode, hole burning imaging (HBI) of cells adhered to coverslips and cooled to liquid helium temperatures in the complete absence of

  4. Identification and use of fluorescent dyes for plant cell wall imaging using high-throughput screening.

    Science.gov (United States)

    Anderson, Charles T; Carroll, Andrew

    2014-01-01

    Plant cell walls define cell shape during development and are composed of interlaced carbohydrate and protein networks. Fluorescent dyes have long been used to label plant cell walls, enabling optical microscopy-based interrogation of cell wall structure and composition. However, the specific cell wall components to which these dyes bind are often poorly defined. The availability of fluorescent compound libraries provides the potential to screen for and identify new fluorescent compounds that interact with specific plant cell wall components, enabling the study of cell wall architecture in intact, living tissues. Here, we describe a technique for screening fluorescent compound libraries for enhanced fluorescence upon interaction with plant cell walls, a secondary screening method to identify which cell wall components interact with a given dye, and a protocol for staining and observing Arabidopsis seedlings using a fluorescent cell wall-labeling dye. These methods have the potential to be applied to screening for differences in cell wall structure and composition among genetically diverse plant varieties or species.

  5. Inhibition of veratridine-induced delayed inactivation of the voltage-sensitive sodium channel by synthetic analogs of crambescin B.

    Science.gov (United States)

    Tsukamoto, Tadaaki; Chiba, Yukie; Nakazaki, Atsuo; Ishikawa, Yuki; Nakane, Yoshiki; Cho, Yuko; Yotsu-Yamashita, Mari; Nishikawa, Toshio; Wakamori, Minoru; Konoki, Keiichi

    2017-03-01

    Crambescin B carboxylic acid, a synthetic analog of crambescin B, was recently found to inhibit the voltage-sensitive sodium channels (VSSC) in a cell-based assay using neuroblastoma Neuro 2A cells. In the present study, whole-cell patch-clamp recordings were conducted with three heterologously expressed VSSC subtypes, Na v 1.2, Na v 1.6 and Na v 1.7, in a human embryonic kidney cell line HEK293T to further characterize the inhibition of VSSC by crambescin B carboxylic acid. Contrary to the previous observation, crambescin B carboxylic acid did not inhibit peak current evoked by depolarization from the holding potential of -100mV to the test potential of -10mV in the absence or presence of veratridine (VTD). In the presence of VTD, however, crambescin B carboxylic acid diminished VTD-induced sustained and tail currents through the three VSSC subtypes in a dose-dependent manner, whereas TTX inhibited both the peak current and the VTD-induced sustained and tail currents through all subtypes of VSSC tested. We thus concluded that crambescin B carboxylic acid does not block VSSC in a similar manner to TTX but modulate the action of VTD, thereby causing an apparent block of VSSC in the cell-based assay. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Far-red and near infrared BODIPY dyes: synthesis and applications for fluorescent pH probes and bio-imaging.

    Science.gov (United States)

    Ni, Yong; Wu, Jishan

    2014-06-21

    Far-red and near infrared (NIR) emissive dyes have advantages in the development of fluorescent probes and labelling for bio-imaging in living systems since fluorescence in the long-wavelength region would generate minimum photo-toxicity to biological components, deep tissue penetration and minimal background from auto-fluorescence by bio-molecules. BODIPY dyes are attractive due to their excellent photo-physical properties and potential for fluorescence-based sensing and bio-imaging applications. Thus, numerous research papers have emerged to develop BODIPY-based dyes with absorption and emission in the long-wavelength spectral region (650-900 nm). This review summarizes the general strategies to obtain far-red and NIR BODIPYs. Moreover, their applications for fluorescent pH probes and imaging or labelling in living systems are highlighted.

  7. Imaging membrane intercalating near infrared dyes to track multiple cell populations.

    Science.gov (United States)

    Roy, Edward J; Sivaguru, Mayandi; Fried, Glenn; Gray, Brian D; Kranz, David M

    2009-08-31

    Given the increasing interest in understanding in vivo migration of different cell types, it would be useful to have a simple method for tracking multiple cell populations in animals. Here we evaluated near infrared (NIR) dyes that intercalate into cell membranes as cell tracking labels, using both high-throughput and high-resolution methods. We tracked cells in tissues containing significant autofluorescence. CellVue Burgundy (ex 683/em 707) and CellVue NIR815 (ex 786/em 814) are especially useful because their spectral properties match the laser and detectors of the LI-COR laser scanner. After labeling cells ex vivo and injecting them into tumor-bearing mice, the distribution of cells in tumor and organs could be quantified in tissue sections with high throughput by scanning many slides at once. For example, we compared brain tumor infiltration and organ distribution of naïve and activated lymphocytes in single animals. High-resolution microscopic examination of the same tissues could be done by a relatively inexpensive modification of an epifluorescence microscope using a custom designed diode laser light source. Light emitting diodes that emit 685 nm and 780 nm light allowed microscopic visualization of the NIR labeled cells in tissues. The NIR dye-labeled cells were visualized with a greater signal/noise ratio compared to visible wavelength dyes such as CFSE, because of the low levels of autofluorescence in the NIR range. We also describe a simple modification of immunohistochemical procedures that allows combined visualization of the hydrophobic NIR dyes and antibody probes of cell markers in unfixed tissue. In combination these techniques will facilitate cell tracking in vivo.

  8. Photoacoustic imaging with an acoustic lens detects prostate cancer cells labeled with PSMA-targeting near-infrared dye-conjugates

    Science.gov (United States)

    Dogra, Vikram; Chinni, Bhargava; Singh, Shalini; Schmitthenner, Hans; Rao, Navalgund; Krolewski, John J.; Nastiuk, Kent L.

    2016-06-01

    There is an urgent need for sensitive and specific tools to accurately image early stage, organ-confined human prostate cancers to facilitate active surveillance and reduce unnecessary treatment. Recently, we developed an acoustic lens that enhances the sensitivity of photoacoustic imaging. Here, we report the use of this device in conjunction with two molecular imaging agents that specifically target the prostate-specific membrane antigen (PSMA) expressed on the tumor cell surface of most prostate cancers. We demonstrate successful imaging of phantoms containing cancer cells labeled with either of two different PSMA-targeting agents, the ribonucleic acid aptamer A10-3.2 and a urea-based peptidomimetic inhibitor, each linked to the near-infrared dye IRDye800CW. By specifically targeting cells with these agents linked to a dye chosen for optimal signal, we are able to discriminate prostate cancer cells that express PSMA.

  9. Imaging of Single Dye-Labeled Chemotaxis Proteins in Live Bacteria Using Electroporation.

    Science.gov (United States)

    Di Paolo, Diana; Berry, Richard M

    2018-01-01

    For the last 2 decades, the use of genetically fused fluorescent proteins (FPs) has greatly contributed to the study of chemotactic signaling in E. coli, including the activation of the response regulator protein CheY and its interaction with the flagellar motor. However, this approach suffers from a number of limitations, both biological and biophysical. For example, not all fusions are fully functional when fused to a bulky FP, which can have a similar molecular weight to its fused counterpart. FPs may interfere with the native interactions of the protein, and their chromophores have low brightness and photostability, and fast photobleaching rates. Electroporation allows for internalization of purified CheY proteins labeled with organic dyes into E. coli cells in controllable concentrations. Using fluorescence video microscopy, it is possible to observe single CheY molecules diffusing within cells and interacting with the sensory clusters and the flagellar motors in real time.

  10. Point mutation of a conserved aspartate, D69, in the muscarinic M2 receptor does not modify voltage-sensitive agonist potency.

    Science.gov (United States)

    Ågren, Richard; Sahlholm, Kristoffer; Nilsson, Johanna; Århem, Peter

    2018-01-29

    The muscarinic M 2 receptor (M 2 R) has been shown to display voltage-sensitive agonist binding, based on G protein-activated inward rectifier potassium channel (GIRK) opening and radioligand binding at different membrane voltages. A conserved aspartate in transmembrane segment (TM) II of M 2 R, D69, has been proposed as the voltage sensor. While a recent paper instead presented evidence of tyrosines in TMs III, VI, and VII acting as voltage sensors, these authors were not able to record GIRK channel activation by a D69N mutant M 2 R. In the present study, we succeeded in recording ACh-induced GIRK channel activation by this mutant at -80 and 0 mV. The acetylcholine EC 50 was about 2.5-fold higher at 0 mV, a potency shift very similar to that observed at wild-type M 2 R, indicating that voltage sensitivity persists at the D69N mutant. Thus, our present observations corroborate the notion that D69 is not responsible for voltage sensitivity of the M 2 R. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Linear and non-linear fluorescence imaging of neuronal activity

    Science.gov (United States)

    Fisher, Jonathan A. N.

    Optical imaging of neuronal activity offers new possibilities for understanding brain physiology. The predominant methods in neuroscience for measuring electrical activity require electrodes inserted into the tissue. Such methods, however, provide limited spatial information and are invasive. Optical methods are less physically invasive and offer the possibility for simultaneously imaging the activity of many neurons. In this thesis one- and two-photon fluorescence microscopy techniques were applied to several in vivo and in vitro mammalian preparations. Using one-photon absorption fluorescence microscopy and gradient index (GRIN) lens optics, cortical electrical activity in response to electric stimulation was resolved in three-dimensions at high-speed in the primary somatosensory cortex of the mouse in vivo using voltage-sensitive dyes. Imaging at depths up to 150 mum below the cortex surface, it was possible to resolve depth-dependent patterns of neuronal activity in response to cortical and thalamic electric stimulation. The patterns of activity were consistent with known cortical cellular architecture. In a qualitatively different set of experiments, one-photon fluorescence microscopy via voltage-sensitive dyes was successfully employed to image an in vitro preparation of the perfused rat brainstem during the process of respiratory rhythmogenesis. Imaging results yielded insights into the spatial organization of the central respiratory rhythm generation region in the ventrolateral medulla. A multifocal two-photon scanning microscope was constructed, and design and operation principles are described. Utilizing the novel device, anatomical and functional two-photon imaging via potentiometric dyes and calcium dyes is described, and the results of in vivo versus in vitro imaging are compared. Anatomical imaging results used either functional probe background fluorescence or green fluorescent protein (GFP) expression. Spectroscopic experiments measuring the two

  12. OPTIMIZATION OF DYEING PARAMETERS TO DYE COTTON WITH CARROT EXTRACTION

    Directory of Open Access Journals (Sweden)

    MIRALLES Verónica

    2017-05-01

    Full Text Available Natural dyes derived from flora and fauna are believed to be safe because of non-toxic, non-carcinogenic and biodegradable nature. Furthermore, natural dyes do not cause pollution and waste water problems. Natural dyes as well as synthetic dyes need the optimum parameters to get a good dyeing. On some occasions, It is necessary the use of mordants to increase the affinity between cellulose fiber and natural dye, but there are other conditions to optimize in the dyeing process, like time, temperature, auxiliary porducts, etc. In addition, the optimum conditions are different depends on the type of dye and the fiber nature. The aim of this work is the use of carrot extract to dye cotton fabric by exhaustion at diverse dyeing conditions. Diffferent dyeing processes were carried out to study the effect of pH condition and the temperature, using 7, 6 and 4 pH values and 95 ºC and 130ºC for an hour. As a result some images of dyed samples are shown. Moreover, to evaluate the colour of each sample CIELAB parameters are analysed obtained by reflexion spectrophotometre. The results showed that the temperature used has an important influence on the colour of the dyed sample.

  13. Voltage imaging to understand connections and functions of neuronal circuits

    Science.gov (United States)

    Antic, Srdjan D.; Empson, Ruth M.

    2016-01-01

    Understanding of the cellular mechanisms underlying brain functions such as cognition and emotions requires monitoring of membrane voltage at the cellular, circuit, and system levels. Seminal voltage-sensitive dye and calcium-sensitive dye imaging studies have demonstrated parallel detection of electrical activity across populations of interconnected neurons in a variety of preparations. A game-changing advance made in recent years has been the conceptualization and development of optogenetic tools, including genetically encoded indicators of voltage (GEVIs) or calcium (GECIs) and genetically encoded light-gated ion channels (actuators, e.g., channelrhodopsin2). Compared with low-molecular-weight calcium and voltage indicators (dyes), the optogenetic imaging approaches are 1) cell type specific, 2) less invasive, 3) able to relate activity and anatomy, and 4) facilitate long-term recordings of individual cells' activities over weeks, thereby allowing direct monitoring of the emergence of learned behaviors and underlying circuit mechanisms. We highlight the potential of novel approaches based on GEVIs and compare those to calcium imaging approaches. We also discuss how novel approaches based on GEVIs (and GECIs) coupled with genetically encoded actuators will promote progress in our knowledge of brain circuits and systems. PMID:27075539

  14. Green and Red Fluorescent Dyes for Translational Applications in Imaging and Sensing Analytes: A Dual-Color Flag.

    Science.gov (United States)

    Oliveira, Elisabete; Bértolo, Emilia; Núñez, Cristina; Pilla, Viviane; Santos, Hugo M; Fernández-Lodeiro, Javier; Fernández-Lodeiro, Adrian; Djafari, Jamila; Capelo, José Luis; Lodeiro, Carlos

    2018-01-01

    Red and green are two of the most-preferred colors from the entire chromatic spectrum, and red and green dyes are widely used in biochemistry, immunohistochemistry, immune-staining, and nanochemistry applications. Selective dyes with green and red excitable chromophores can be used in biological environments, such as tissues and cells, and can be irradiated with visible light without cell damage. This critical review, covering a period of five years, provides an overview of the most-relevant results on the use of red and green fluorescent dyes in the fields of bio-, chemo- and nanoscience. The review focuses on fluorescent dyes containing chromophores such as fluorescein, rhodamine, cyanine, boron-dipyrromethene (BODIPY), 7-nitobenz-2-oxa-1,3-diazole-4-yl, naphthalimide, acridine orange, perylene diimides, coumarins, rosamine, Nile red, naphthalene diimide, distyrylpyridinium, benzophosphole P-oxide, benzoresorufins, and tetrapyrrolic macrocycles. Metal complexes and nanomaterials with these dyes are also discussed.

  15. Voltage sensitivity based reactive power control on VSC-HVDC in a wind farm connected hybrid multi-infeed HVDC system

    DEFF Research Database (Denmark)

    Liu, Yan; Chen, Zhe

    2013-01-01

    With increasing application of both Line Commutated Converter based High Voltage Direct Current (LCC-HVDC) systems and Voltage Source Converter based HVDC (VSC-HVDC) links, a new type of system structure named Hybrid Multi-Infeed HVDC (HMIDC) system is formed in the modern power systems. This paper...... presents the operation and control method of the wind farm connected HMIDC system. The wind power fluctuation takes large influence to the system voltages. In order to reduce the voltage fluctuation of LCC-HVDC infeed bus caused by the wind power variation, a voltage sensitivity-based reactive power...

  16. Synthesis of fluorescent dye-doped silica nanoparticles for target-cell-specific delivery and intracellular microRNA imaging.

    Science.gov (United States)

    Li, Henan; Mu, Yawen; Qian, Shanshan; Lu, Jusheng; Wan, Yakun; Fu, Guodong; Liu, Songqin

    2015-01-21

    MicroRNA (miRNA) is found to be up-regulated in many kinds of cancer and therefore is classified as an oncomiR. Herein, we design a multifunctional fluorescent nanoprobe (FSiNP-AS/MB) with the AS1411 aptamer and a molecular beacon (MB) co-immobilized on the surface of the fluorescent dye-doped silica nanoparticles (FSiNPs) for target-cell-specific delivery and intracellular miRNA imaging. The FSiNPs were prepared by a facile reverse microemulsion method from tetraethoxysilane and silane derivatized coumarin that was previously synthesized by click chemistry. The as-prepared FSiNPs possess uniform size distribution, good optical stability and biocompatibility. In addition, there is a remarkable affinity interaction between the AS1411 aptamer and the nucleolin protein on the cancer cell surface. Thus, a target-cell-specific delivery system by the FSiNP-AS/MB is proposed for effectively transferring a MB into the cancer cells to recognize the target miRNA. Using miRNA-21 in MCF-7 cells (a human breast cancer cell line) as a model, the proposed multifunctional nanosystems not only allow target-cell-specific delivery with the binding affinity of AS1411, but also can track simultaneously the transfected cells and detect intracellular miRNA in situ. The proposed multifunctional nanosystems are a promising platform for a highly sensitive luminescent nonviral vector in biomedical and clinical research.

  17. Nanoimprinted distributed feedback dye laser sensors for high frame rate refractometric imaging of dissolution and fluid flow

    DEFF Research Database (Denmark)

    Vannahme, Christoph; Sørensen, Kristian Tølbøl; Gade, Carsten

    2015-01-01

    High frame rate refractometric dissolution and fluid flow monitoring in one and two dimensions of space with distributed feedback dye laser sensors is presented. The sensors provide both low detection limits and high spatial resolution. © 2015 OSA.......High frame rate refractometric dissolution and fluid flow monitoring in one and two dimensions of space with distributed feedback dye laser sensors is presented. The sensors provide both low detection limits and high spatial resolution. © 2015 OSA....

  18. Dye lasers

    Energy Technology Data Exchange (ETDEWEB)

    Kuder, J.E.; McGinnis, J.L.; Goldberg, H.A.; Hart, T.R.; Che, T.M.

    1989-10-31

    This patent describes a dye laser. It consists of a composite composition of an inorganic oxide glass monolith with a microporous structure containing an incorporated solution comprising a solvent component and a lasable dye component. Wherein the glass monolith has sealed outer surfaces.

  19. Surface grafting of zwitterionic polymers onto dye doped AIE-active luminescent silica nanoparticles through surface-initiated ATRP for biological imaging applications

    Science.gov (United States)

    Mao, Liucheng; Liu, Xinhua; Liu, Meiying; Huang, Long; Xu, Dazhuang; Jiang, Ruming; Huang, Qiang; Wen, Yuanqing; Zhang, Xiaoyong; Wei, Yen

    2017-10-01

    Aggregation-induced emission (AIE) dyes have recently been intensively explored for biological imaging applications owing to their outstanding optical feature as compared with conventional organic dyes. The AIE-active luminescent silica nanoparticles (LSNPs) are expected to combine the advantages both of silica nanoparticles and AIE-active dyes. Although the AIE-active LSNPs have been prepared previously, surface modification of these AIE-active LSNPs with functional polymers has not been reported thus far. In this work, we reported a rather facile and general strategy for preparation of polymers functionalized AIE-active LSNPs through the surface-initiated atom transfer radical polymerization (ATRP). The AIE-active LSNPs were fabricated via direct encapsulation of AIE-active dye into silica nanoparticles through a non-covalent modified Stöber method. The ATRP initiator was subsequently immobilized onto these AIE-active LSNPs through amidation reaction between 3-aminopropyl-triethoxy-silane and 2-bromoisobutyryl bromide. Finally, the zwitterionic 2-(methacryloyloxy)ethyl phosphorylcholine (MPC) was selected as model monomer and grafted onto MSNs through ATRP. The characterization results suggested that LSNPs can be successfully modified with poly(MPC) through surface-initiated ATRP. The biological evaluation results demonstrated that the final SNPs-AIE-pMPC composites possess low cytotoxicity, desirable optical properties and great potential for biological imaging. Taken together, we demonstrated that AIE-active LSNPs can be fabricated and surface modified with functional polymers to endow novel functions and better performance for biomedical applications. More importantly, this strategy developed in this work could also be extended for fabrication of many other LSNPs polymer composites owing to the good monomer adoptability of ATRP.

  20. In vivo magnetic resonance and fluorescence dual imaging of tumor sites by using dye-doped silica-coated iron oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Haeyun; Lee, Chaedong [Seoul National University, Program in Nano Science and Technology, Graduate School of Convergence Science and Technology (Korea, Republic of); Nam, Gi-Eun [University of Ulsan College of Medicine, Department of Radiology, Asan Medical Center (Korea, Republic of); Quan, Bo [Seoul National University, Program in Nano Science and Technology, Graduate School of Convergence Science and Technology (Korea, Republic of); Choi, Hyuck Jae [University of Ulsan College of Medicine, Department of Radiology, Asan Medical Center (Korea, Republic of); Yoo, Jung Sun [Seoul National University, Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Smart Humanity Convergence Center (Korea, Republic of); Piao, Yuanzhe, E-mail: parkat9@snu.ac.kr [Seoul National University, Program in Nano Science and Technology, Graduate School of Convergence Science and Technology (Korea, Republic of)

    2016-02-15

    The difficulty in delineating tumor is a major obstacle for better outcomes in cancer treatment of patients. The use of single-imaging modality is often limited by inadequate sensitivity and resolution. Here, we present the synthesis and the use of monodisperse iron oxide nanoparticles coated with fluorescent silica nano-shells for fluorescence and magnetic resonance dual imaging of tumor. The as-synthesized core–shell nanoparticles were designed to improve the accuracy of diagnosis via simultaneous tumor imaging with dual imaging modalities by a single injection of contrast agent. The iron oxide nanocrystals (∼11 nm) were coated with Rhodamine B isothiocyanate-doped silica shells via reverse microemulsion method. Then, the core–shell nanoparticles (∼54 nm) were analyzed to confirm their size distribution by transmission electron microscopy and dynamic laser scattering. Photoluminescence spectroscopy was used to characterize the fluorescent property of the dye-doped silica shell-coated nanoparticles. The cellular compatibility of the as-prepared nanoparticles was confirmed by a trypan blue dye exclusion assay and the potential as a dual-imaging contrast agent was verified by in vivo fluorescence and magnetic resonance imaging. The experimental results show that the uniform-sized core–shell nanoparticles are highly water dispersible and the cellular toxicity of the nanoparticles is negligible. In vivo fluorescence imaging demonstrates the capability of the developed nanoparticles to selectively target tumors by the enhanced permeability and retention effects and ex vivo tissue analysis was corroborated this. Through in vitro phantom test, the core/shell nanoparticles showed a T2 relaxation time comparable to Feridex{sup ®} with smaller size, indicating that the as-made nanoparticles are suitable for imaging tumor. This new dual-modality-nanoparticle approach has promised for enabling more accurate tumor imaging.

  1. Experimental and DFT Studies: Novel Structural Modifications Greatly Enhance the Solvent Sensitivity of Live Cell Imaging Dyes

    Science.gov (United States)

    Toutchkine, Alexei; Han, Wen-Ge; Ullmann, Matthias; Liu, Tiqing; Bashford, Donald; Noodleman, Louis; Hahn, Klaus M.

    2013-01-01

    Structural modifications of previously reported merocyanine dyes (J. Am. Chem. Soc. 2003, 125, 4132–4145) were found to greatly enhance the solvent dependence of their absorbance and fluorescence emission maxima. Density functional theory (DFT) calculations have been performed to understand the differences in optical properties between the new and previously synthesized dyes. Absorption and emission energies were calculated for several new dyes using DFT vertical self-consistent reaction field methods (VSCRF). Geometries of ground and excited states were optimized with a Conductor-like screening model (COSMO) and self-consistent-field (SCF) methods. The new dyes have enhanced zwitterionic character in the ground state, and much lower polarity in the excited state, as shown by the DFT-VSCRF calculations. Consistently, the position of the absorption bands are strongly blue-shifted in more polar solvent (methanol compared to benzene) as predicted by the DFT spectral calculations. Inclusion of explicit H-bonding solvent molecules within the quantum model further enhances the predicted shifts, and is consistent with the observed spectral broadening. Smaller, but significant spectral shifts in polar versus nonpolar solvent are predicted and observed for emission bands. The new dyes show large fluorescence quantum yields in polar hydrogen bonding solvents; qualitatively, the longest bonds along the conjugated chain at the excited S1 state minimum are shorter in the more polar solvent, inhibiting photoisomerization. The loss of photostability of the dyes is a consequence of the reaction with and electron transfer to singlet oxygen, starting oxidative dye cleavage. The calculated vertical ionization potentials of three dyes I-SO, AI-SO(4), and AI-BA(4) in benzene and methanol are consistent with their relative photobleaching rates; the charge distributions along the conjugated chains for the three dyes are similarly predictive of higher reaction rates for AI-SO(4) and AI

  2. Green and Red Fluorescent Dyes for Translational Applications in Imaging and Sensing Analytes: A Dual‐Color Flag

    Science.gov (United States)

    Oliveira, Elisabete; Bértolo, Emilia; Núñez, Cristina; Pilla, Viviane; Santos, Hugo M.; Fernández‐Lodeiro, Javier; Fernández‐Lodeiro, Adrian; Djafari, Jamila; Capelo, José Luis

    2017-01-01

    Abstract Red and green are two of the most‐preferred colors from the entire chromatic spectrum, and red and green dyes are widely used in biochemistry, immunohistochemistry, immune‐staining, and nanochemistry applications. Selective dyes with green and red excitable chromophores can be used in biological environments, such as tissues and cells, and can be irradiated with visible light without cell damage. This critical review, covering a period of five years, provides an overview of the most‐relevant results on the use of red and green fluorescent dyes in the fields of bio‐, chemo‐ and nanoscience. The review focuses on fluorescent dyes containing chromophores such as fluorescein, rhodamine, cyanine, boron–dipyrromethene (BODIPY), 7‐nitobenz‐2‐oxa‐1,3‐diazole‐4‐yl, naphthalimide, acridine orange, perylene diimides, coumarins, rosamine, Nile red, naphthalene diimide, distyrylpyridinium, benzophosphole P‐oxide, benzoresorufins, and tetrapyrrolic macrocycles. Metal complexes and nanomaterials with these dyes are also discussed. PMID:29318095

  3. A high content imaging flow cytometry approach to study mitochondria in T cells: MitoTracker Green FM dye concentration optimization.

    Science.gov (United States)

    Gautam, Namrata; Sankaran, Shvetha; Yason, John A; Tan, Kevin S W; Gascoigne, Nicholas R J

    2018-02-01

    Mitochondria, the powerhouse of the cell, are known to remodel their membrane structures through the process of fusion or fission. Studies have indicated that T cells adopt different energy metabolic phenotypes, namely oxidative phosphorylation and glycolysis depending on whether they are naïve, effector and memory T cells. It has recently been shown that changes in mitochondrial morphology dictate T cell fate via regulation of their metabolism. Our keen interest in T cell function and metabolism led us to explore and establish a method to study mitochondria in live T cells through a novel high content approach called Imaging Flow Cytometry (IFC). The focus of our current study was on developing a protocol to standardize the concentration of MitoTracker Green FM dye to observe mitochondria in live T cells using IFC. We began the study by using widefield microscopy to confirm the localisation of MitoTracker Green FM labelled mitochondria in live T cells. This was followed by testing various concentrations of the dye to achieve a similar labelling pattern using IFC while eliminating false positive or negative staining. The optimization of the method used to label the mitochondria by IFC for analysis included standardisation of a number of important parameters such as dye concentration, voltage, fluorescence intensity values for acquisition and processing. IFC could potentially be a powerful method to study T cells in a relatively high throughput manner. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Textile dyes

    OpenAIRE

    Guaratini, Cláudia C. I. [UNESP; Zanoni, Maria Valnice Boldrin [UNESP

    2000-01-01

    A dye is a colored substance used to impart permanent color to other substances. Its most important use is in coloring textile fibers and fabrics. The removal of colour from dyehouse waste waters is currently a major problem in the textile sector. This paper provides an overview of the treatment technologies that can currently be used by the textile processor and the developments over the past decade with respect to the toxicological and ecotoxicological properties of synthetic organic dyes.

  5. Nonphotochemical Hole-Burning Imaging Studies of In Vitro Carcinoma and Normal Cells Utilizing a Mitochondrial Specific Dye

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, Richard Joseph [Iowa State Univ., Ames, IA (United States)

    2002-01-01

    Low temperature Nonphotochemical Hole Burning (NPHB) Spectroscopy of the dye rhodamine 800 (MF680) was applied for the purpose of discerning differences between cultured normal and carcinoma ovarian surface epithelial (OSE) cells. Both the cell lines were developed and characterized at the Mayo Clinic (Rochester, MN), with the normal cell line having been transfected with a strain of temperature sensitive Simian Virus 40 Large T Antigen (SV40) for the purpose of extending the life of the cell culture without inducing permanent changes in the characteristics of the cell line. The cationic lipophilic fluorophore rhodamine 800 preferentially locates in in situ mitochondria due to the high lipid composition of mitochondria and the generation of a large negative membrane potential (relative to the cellular cytoplasm) for oxidative phosphorylation. Results presented for NPHB of MF680 located in the cells show significant differences between the two cell lines. The results are interpreted on the basis of the NPHB mechanism and characteristic interactions between the host (cellular mitochondrial) and the guest (MF680) in the burning of spectral holes, thus providing an image of the cellular ultrastructure. Hole growth kinetics (HGK) were found to differ markedly between the two cell lines, with the carcinoma cell line burning at a faster average rate for the same exposure fluence. Theoretical fits to the data suggest a lower degree of structural heterogeneity in the carcinoma cell line relative to the normal cell line. Measurement of changes in the permanent dipole moment (fΔμ)were accomplished by measurement of changes in hole width in response to the application of an external electric field (the Stark effect), and found that Δμ values for the carcinoma line were 1.5x greater than those of the SV40 antigen-free normal analogs. These findings are interpreted in terms of effects from the mitochondrial membrane potential. Results for HGK on the scale of single cells is

  6. Nonphotochemical Hole-Burning Imaging Studies of in vitro Carcinoma and Normal Cells Utilizing a Mitochondrial Specific Dye

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, Richard Joseph [Iowa State Univ., Ames, IA (United States)

    2002-01-01

    Low temperature Nonphotochemical Hole Burning (NPHB) Spectroscopy of the dye rhodamine 800 (MF680) was applied for the purpose of discerning differences between cultured normal and carcinoma ovarian surface epithelial (OSE) cells. Both the cell lines were developed and characterized at the Mayo Clinic (Rochester, MN), with the normal cell line having been transfected with a strain of temperature sensitive Simian Virus 40 Large T Antigen (SV40) for the purpose of extending the life of the cell culture without inducing permanent changes in the characteristics of the cell line. The cationic lipophilic fluorophore rhodamine 800 preferentially locates in in situ mitochondria due to the high lipid composition of mitochondria and the generation of a large negative membrane potential (relative to the cellular cytoplasm) for oxidative phosphorylation. Results presented for NPHB of MF680 located in the cells show significant differences between the two cell lines. The results are interpreted on the basis of the NPHB mechanism and characteristic interactions between the host (cellular mitochondrial) and the guest (MF680) in the burning of spectral holes, thus providing an image of the cellular ultrastructure. Hole growth kinetics (HGK) were found to differ markedly between the two cell lines, with the carcinoma cell line burning at a faster average rate for the same exposure fluence. Theoretical fits to the data suggest a lower degree of structural heterogeneity in the carcinoma cell line relative to the normal cell line. Measurement of changes in the permanent dipole moment (fΔμ) were accomplished by measurement of changes in hole width in response to the application of an external electric field (the Stark effect), and found that Δμ values for the carcinoma line were 1.5x greater than those of the SV40 antigen-free normal analogs. These findings are interpreted in terms of effects from the mitochondrial membrane potential. Results for HGK on the scale of single cells is

  7. Comparative tumor imaging and PDT Efficacy of HPPH conjugated in the mono- and di-forms to various polymethine cyanine dyes: part - 2.

    Science.gov (United States)

    James, Nadine S; Ohulchanskyy, Tymish Y; Chen, Yihui; Joshi, Penny; Zheng, Xiang; Goswami, Lalit N; Pandey, Ravindra K

    2013-01-01

    Previous reports from our laboratory have shown that a bifunctional agent obtained by conjugating a photosensitizer (HPPH) to a cyanine dye (CD) can be used for fluorescence image-guided treatment of tumor by photodynamic therapy (PDT). However, the resulting HPPH-CD conjugate showed a significant difference between the tumor-imaging and therapeutic doses. It was demonstrated that the singlet oxygen ( (1) O 2 (*), a key cytotoxic agent in PDT) produced by the conjugate upon excitation of the HPPH moiety was partially quenched by the CD-moiety; this resulted in a reduced PDT response when compared to HPPH-PDT under similar treatment parameters. To improve the therapeutic potential of the conjugate, we synthesized a series of dual functional agents in which one or two HPPH moieties were separately conjugated to three different dyes (Cypate, modified IR820 or modified IR783). The newly synthesized conjugates were compared with our lead compound HPPH-CD in terms of photophysical properties, in vitro and in vivo PDT efficacy, tumor uptake and imaging potential. Among the analogs investigated, the conjugate, in which two HPPH moieties were linked to the modified IR820 produced enhanced tumor uptake and tumor contrast in both Colon 26 (a murine Colon carcinoma) and U87 (a human glioblastoma) cell lines. The long-term PDT efficacy (cure) of this conjugate in BALB/c mice, bearing Colon 26 tumors was also enhanced; however, its efficacy in Nude mice bearing U87 tumors was slightly reduced. It was also found that in all the conjugates the singlet oxygen generation and, consequently, PDT efficacy were compromised by a competing pathway, whereby an electronic excitation of HPPH, the energy donor, is deactivated through an electronic excitation energy transfer (Forster Resonance Energy Transfer, FRET) to the CD fluorophore, the energy acceptor, resulting in overall reduction of the singlet oxygen production. Conjugates with increased FRET showed reduced singlet oxygen production

  8. Hair Dye

    African Journals Online (AJOL)

    cosmetics, temporary tattoos, photographic development and lithography plates, photocopying and printing inks, black rubber, oils, greases and gasoline [2]. PPD is the most common constituent of hair dye formulations. It is often the key ingredient but can also be used for color enhancement. PPD is commonly used.

  9. Laser Dyes

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 9. Laser Dyes. G S Shankarling K J Jarag. General Article Volume 15 Issue 9 September ... Author Affiliations. G S Shankarling1 K J Jarag1. Dyestuff Technology, Department Institute of Chemical Technology, Matunga Mumbai 400 019, India.

  10. Reduced voltage sensitivity of activation of P/Q-type Ca2+ channels is associated with the ataxic mouse mutation rolling Nagoya (tg(rol)).

    Science.gov (United States)

    Mori, Y; Wakamori, M; Oda, S; Fletcher, C F; Sekiguchi, N; Mori, E; Copeland, N G; Jenkins, N A; Matsushita, K; Matsuyama, Z; Imoto, K

    2000-08-01

    Recent genetic analyses have revealed an important association of the gene encoding the P/Q-type voltage-dependent Ca(2+) channel alpha(1A) subunit with hereditary neurological disorders. We have identified the ataxic mouse mutation, rolling Nagoya (tg(rol)), in the alpha(1A) gene that leads to a charge-neutralizing arginine-to-glycine substitution at position 1262 in the voltage sensor-forming segment S4 in repeat III. Ca(2+) channel currents in acutely dissociated Purkinje cells, where P-type is the dominant type, showed a marked decrease in slope and a depolarizing shift by 8 mV of the conductance-voltage curve and reduction in current density in tg(rol) mouse cerebella, compared with those in wild-type. Compatible functional change was induced by the tg(rol) mutation in the recombinant alpha(1A) channel, indicating that a defect in voltage sensor of P/Q-type Ca(2+) channels is the direct consequence of the tg(rol) mutation. Furthermore, somatic whole-cell recording of mutant Purkinje cells displayed only abortive Na(+) burst activity and hardly exhibited Ca(2+) spike activity in cerebellar slices. Thus, in tg(rol) mice, reduced voltage sensitivity, which may derive from a gating charge defect, and diminished activity of the P-type alpha(1A) Ca(2+) channel significantly impair integrative properties of Purkinje neurons, presumably resulting in locomotor deficits.

  11. Waterless Textile Dyeing

    OpenAIRE

    ODABAŞOĞLU, Hakkı Yasin; AVİNÇ, Osman Ozan; YAVAŞ, Arzu

    2013-01-01

    Supercritical carbon dioxide (scCO), having liquid-like densities, hereby provides hydrophobic dyes an advantage on dissolving. Their gas-like low viscosities and diffusion properties can lead to shorter dyeing durations compared to conventional water dyeing process. Supercritical carbon dioxide dyeing, a novel dyeing process, is an anhydrous dyeing and this process involves the use of less energy and chemicals than conventional water dyeing processes resulting in a potential of up to 50% low...

  12. Interactions of phosphatase and tensin homologue (PTEN) proteins with phosphatidylinositol phosphates: insights from molecular dynamics simulations of PTEN and voltage sensitive phosphatase.

    Science.gov (United States)

    Kalli, Antreas C; Devaney, Isabel; Sansom, Mark S P

    2014-03-25

    The phosphatase and tensin homologue (PTEN) and the Ciona intestinalis voltage sensitive phosphatase (Ci-VSP) are both phosphatidylinositol phosphate (PIP) phosphatases that contain a C2 domain. PTEN is a tumor suppressor protein that acts as a phosphatase on PIP3 in mammalian cell membranes. It contains two principal domains: a phosphatase domain (PD) and a C2 domain. Despite detailed structural and functional characterization, less is known about its mechanism of interaction with PIP-containing lipid bilayers. Ci-VSP consists of an N-terminal transmembrane voltage sensor domain and a C-terminal PTEN domain, which in turn contains a PD and a C2 domain. The nature of the interaction of the PTEN domain of Ci-VSP with membranes has not been well established. We have used multiscale molecular dynamics simulations to define the interaction mechanisms of PTEN and of the Ci-VSP PTEN domains with PIP-containing lipid bilayers. Our results suggest a novel mechanism of association of the PTEN with such bilayers, in which an initial electrostatics-driven encounter of the protein and bilayer is followed by reorientation of the protein to optimize its interactions with PIP molecules in the membrane. Although a PIP3 molecule binds close to the active site of PTEN, our simulations suggest a further conformational change of the protein may be required for catalytically productive binding to occur. Ci-VSP interacted with membranes in an orientation comparable to that of PTEN but bound directly to PIP-containing membranes without a subsequent reorientation step. Again, PIP3 bound close to the active site of the Ci-VSP PD, but not in a catalytically productive manner. Interactions of Ci-VSP with the bilayer induced clustering of PIP molecules around the protein.

  13. Nano-dyeing

    Directory of Open Access Journals (Sweden)

    Ning Cui-Juan

    2016-01-01

    Full Text Available Dyeing nanofibers is a frontier of both modern textile engineering and nanotechnology. This paper suggest a feasible method for dyeing nanofibers with a natural red (Roselle Calyx by bubble electrospinning. Reactive dye (Red S3B and acid dye (Red 2B were also used in the experiment for comparison. The dyeing process was finished during the spinning process.

  14. Radioiodinated (aminostyryl)pyridinium (ASP) dyes: New cell membrane probes for labeling mixed leukocytes and lymphocytes for diagnostic imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, Carol; Mease, Ronnie C.; Avren, Lee; Le, Truc; Sabet, Hassan; McAfee, John G

    1996-05-01

    We prepared [({sup 125}I({sup 131}I))]iodo-(aminostyryl)pyridinium dyes from tributylstannyl precursors. ASP 7a and 7b labeled leukocytes ex vivo (70-94%) using saline with or without washing plasma from cells. Viability of peripheral blood lymphocytes (PBLs) (dogs, rats) and splenic lymphocytes (rats) labeled with 7a and 7b (71-82%) was unchanged after labeling ({>=}88%). Canine 7b-leukocytes showed higher uptake in inflammatory lesions than did {sup 111}In-oxine leukocytes. At 3 h, aspirates contained more radioiodine than {sup 111}In (1.65:1 to 22:1) and radioiodine was cell bound. ROI measurements (3 h) gave abscess to contralateral knee ratios of 12.3 and 10.6 for {sup 131}I-7b vs. 4.8 and 2.3 for {sup 111}In-oxine.

  15. Hair dye poisoning

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/002703.htm Hair dye poisoning To use the sharing features on this page, please enable JavaScript. Hair dye poisoning occurs when someone swallows dye or tint ...

  16. Thiophene-based dyes for probing membranes.

    Science.gov (United States)

    López-Duarte, Ismael; Chairatana, Phoom; Wu, Yilei; Pérez-Moreno, Javier; Bennett, Philip M; Reeve, James E; Boczarow, Igor; Kaluza, Wojciech; Hosny, Neveen A; Stranks, Samuel D; Nicholas, Robin J; Clays, Koen; Kuimova, Marina K; Anderson, Harry L

    2015-03-28

    We report the synthesis of four new cationic dipolar push–pull dyes, together with an evaluation of their photophysical and photobiological characteristics pertinent to imaging membranes by fluorescence and second harmonic generation (SHG). All four dyes consist of an N,N-diethylaniline electron-donor conjugated to a pyridinium electron-acceptor via a thiophene bridge, with either vinylene (–CH=CH–) or ethynylene (–C≡C–) linking groups, and with either singly-charged or doubly-charged pyridinium terminals. The absorption and fluorescence behavior of these dyes were compared to a commercially available fluorescent membrane stain, the styryl dye FM4-64. The hyperpolarizabilities of all dyes were compared using hyper-Rayleigh scattering at 800 nm. Cellular uptake, localization, toxicity and phototoxicity were evaluated using tissue cell cultures (HeLa, SK-OV-3 and MDA-231). Replacing the central alkene bridge of FM4-64 with a thiophene does not substantially change the absorption, fluorescence or hyperpolarizability, whereas changing the vinylene-links to ethynylenes shifts the absorption and fluorescence to shorter wavelengths, and reduces the hyperpolarizability by about a factor of two. SHG and fluorescence imaging experiments in live cells showed that the doubly-charged thiophene dyes localize in plasma membranes, and exhibit lower internalization rates compared to FM4-64, resulting in less signal from the cell cytosol. At a typical imaging concentration of 1 μM, the doubly-charged dyes showed no significant light or dark toxicity, whereas the singly-charged dyes are phototoxic even at 0.5 μM. The doubly-charged dyes showed phototoxicity at concentrations greater than 10 μM, although they do not generate singlet oxygen, indicating that the phototoxicity is type I rather than type II. The doubly-charged thiophene dyes are more effective than FM4-64 as SHG dyes for live cells.

  17. Dyeing of hydrophobic fabrics with disperse dyes

    Directory of Open Access Journals (Sweden)

    VITHAL SOMA PATEL

    2001-06-01

    Full Text Available A series of disperse dyes has been synthesized by diazotisation of 2,6-dibromo-4-nitroaniline and coupled with various N-arylmaleimides. The dyes were characterized by IR spectral studies, visible absorption spectroscopy and elemental analysis. All the dyes were applied as disperse dyes on nylon, cellulose triacetate and polyester fabrics. These dyeswere found to give yellowish orange to deep brown shades with very good depth, levelness and brightness on different fabrics. The percentage dye bath exhaustion and fixation on fabrics were found to be very good. The light, washing, rubbing, perspiration and sublimation fastness properties of the dyed fabrics were found to be good to excellent.

  18. Interaction of Sensitizing Dyes with Nanostructured TiO2 Film in Dye-Sensitized Solar Cells Using Terahertz Spectroscopy.

    Science.gov (United States)

    Ghann, William; Rahman, Aunik; Rahman, Anis; Uddin, Jamal

    2016-07-22

    The objective of this investigation was to shed light on the nature of interaction of different organic dyes and an inorganic dye, Ruthenium (II) polypyridine complex, with TiO2 nanoparticles. TiO2 is commonly deployed as an efficient energy transfer electrode in dye sensitized solar cells. The efficiency of dye sensitized solar cells is a function of the interaction of a dye with the electrode material such as TiO2. To the best of our knowledge the present study is the first effort in the determination of terahertz absorbance signals, investigation of real-time dye permeation kinetics, and the surface profiling and 3D imaging of dye sensitized TiO2 films. Herein, we report that the terahertz spectra of the natural dye sensitized TiO2 films were distinctively different from that of the inorganic dye with prominent absorption of natural dyes occurring at approximately the same wavelength. It was observed that the permeation of the natural dyes were more uniform through the layers of the mesoporous TiO2 compared to the inorganic dye. Finally, defects and flaws on TiO2 film were easily recognized via surface profiling and 3D imaging of the films. The findings thus offer a new approach in characterization of dye sensitized solar cells.

  19. Local Delivery of Fluorescent Dye For Fiber-Optics Confocal Microscopy of the Living Heart

    Directory of Open Access Journals (Sweden)

    Chao eHuang

    2014-09-01

    Full Text Available Fiber-optics confocal microscopy (FCM is an emerging imaging technology with various applications in basic research and clinical diagnosis. FCM allows for real-time in situ microscopy of tissue at sub-cellular scale. Recently FCM has been investigated for cardiac imaging, in particular, for discrimination of cardiac tissue during pediatric open-heart surgery. FCM relies on fluorescent dyes. The current clinical approach of dye delivery is based on systemic injection, which is associated with high dye consumption and adverse clinical events. In this study, we investigated approaches for local dye delivery during FCM imaging based on dye carriers attached to the imaging probe. Using three-dimensional confocal microscopy, automated bench tests, and FCM imaging we quantitatively characterized dye release of carriers composed of open-pore foam only and foam loaded with agarose hydrogel. In addition, we compared local dye delivery with a model of systemic dye delivery in the isolated perfused rodent heart. We measured the signal-to-noise ratio of images acquired in various regions of the heart. Our evaluations showed that foam-agarose dye carriers exhibited a prolonged dye release versus foam-only carriers. Foam-agarose dye carriers allowed reliable imaging of 5-9 lines, which is comparable to 4-8 min of continuous dye release. Our study in the living heart revealed that the SNR of FCM images using local and systemic dye delivery is not different. However, we observed differences in the imaged tissue microstructure with the two approaches. Structural features characteristic of microvasculature were solely observed for systemic dye delivery. Our findings suggest that local dye delivery approach for FCM imaging constitutes an important alternative to systemic dye delivery. We suggest that the approach for local dye delivery will facilitate clinical translation of FCM, for instance, for FCM imaging during pediatric heart surgery.

  20. Local delivery of fluorescent dye for fiber-optics confocal microscopy of the living heart.

    Science.gov (United States)

    Huang, Chao; Kaza, Aditya K; Hitchcock, Robert W; Sachse, Frank B

    2014-01-01

    Fiber-optics confocal microscopy (FCM) is an emerging imaging technology with various applications in basic research and clinical diagnosis. FCM allows for real-time in situ microscopy of tissue at sub-cellular scale. Recently FCM has been investigated for cardiac imaging, in particular, for discrimination of cardiac tissue during pediatric open-heart surgery. FCM relies on fluorescent dyes. The current clinical approach of dye delivery is based on systemic injection, which is associated with high dye consumption, and adverse clinical events. In this study, we investigated approaches for local dye delivery during FCM imaging based on dye carriers attached to the imaging probe. Using three-dimensional confocal microscopy, automated bench tests, and FCM imaging we quantitatively characterized dye release of carriers composed of open-pore foam only and foam loaded with agarose hydrogel. In addition, we compared local dye delivery with a model of systemic dye delivery in the isolated perfused rodent heart. We measured the signal-to-noise ratio (SNR) of images acquired in various regions of the heart. Our evaluations showed that foam-agarose dye carriers exhibited a prolonged dye release vs. foam-only carriers. Foam-agarose dye carriers allowed reliable imaging of 5-9 lines, which is comparable to 4-8 min of continuous dye release. Our study in the living heart revealed that the SNR of FCM images using local and systemic dye delivery is not different. However, we observed differences in the imaged tissue microstructure with the two approaches. Structural features characteristic of microvasculature were solely observed for systemic dye delivery. Our findings suggest that local dye delivery approach for FCM imaging constitutes an important alternative to systemic dye delivery. We suggest that the approach for local dye delivery will facilitate clinical translation of FCM, for instance, for FCM imaging during pediatric heart surgery.

  1. Functional brain fluorescence plurimetry in rat by implantable concatenated CMOS imaging system.

    Science.gov (United States)

    Kobayashi, Takuma; Masuda, Hiroyuki; Kitsumoto, Chikara; Haruta, Makito; Motoyama, Mayumi; Ohta, Yasumi; Noda, Toshihiko; Sasagawa, Kiyotaka; Tokuda, Takashi; Shiosaka, Sadao; Ohta, Jun

    2014-03-15

    Measurement of brain activity in multiple areas simultaneously by minimally invasive methods contributes to the study of neuroscience and development of brain machine interfaces. However, this requires compact wearable instruments that do not inhibit natural movements. Application of optical potentiometry with voltage-sensitive fluorescent dye using an implantable image sensor is also useful. However, the increasing number of leads required for the multiple wired sensors to measure larger domains inhibits natural behavior. For imaging broad areas by numerous sensors without excessive wiring, a web-like sensor that can wrap the brain was developed. Kaleidoscopic potentiometry is possible using the imaging system with concatenated sensors by changing the alignment of the sensors. This paper describes organization of the system, evaluation of the system by a fluorescence imaging, and finally, functional brain fluorescence plurimetry by the sensor. The recorded data in rat somatosensory cortex using the developed multiple-area imaging system compared well with electrophysiology results. © 2013 Elsevier B.V. All rights reserved.

  2. Unveiling NIR Aza-Boron-Dipyrromethene (BODIPY) Dyes as Raman Probes: Surface-Enhanced Raman Scattering (SERS)-Guided Selective Detection and Imaging of Human Cancer Cells.

    Science.gov (United States)

    Adarsh, Nagappanpillai; Ramya, Adukkadan N; Maiti, Kaustabh Kumar; Ramaiah, Danaboyina

    2017-10-12

    The development of new Raman reporters has attracted immense attention in diagnostic research based on surface enhanced Raman scattering (SERS) techniques, which is a well established method for ultrasensitive detection through molecular fingerprinting and imaging. Herein, for the first time, we report the unique and efficient Raman active features of the selected aza-BODIPY dyes 1-6. These distinctive attributes could be extended at the molecular level to allow detection through SERS upon adsorption onto nano-roughened gold surface. Among the newly revealed Raman reporters, the amino substituted derivative 4 showed high signal intensity at very low concentrations (ca. 0.4 μm for 4-Au). Interestingly, an efficient nanoprobe has been constructed by using gold nanoparticles as SERS substrate, and 4 as the Raman reporter (4-Au@PEG), which unexpectedly showed efficient recognition of three human cancer cells (lung: A549, cervical: HeLa, Fibrosarcoma: HT-1080) without any specific surface marker. We observed well reflected and resolved Raman mapping and characteristic signature peaks whereas, such recognition was not observed in normal fibroblast (3T3L1) cells. To confirm these findings, a SERS nanoprobe was conjugated with a specific tumour targeting marker, EGFR (Epidermal Growth Factor Receptor), a well known targeted agent for Human Fibrosarcoma (HT1080). This nanoprobe efficiently targeted the surface marker of HT1080 cells, threreby demonstrating its use as an ultrasensitive Raman probe for detection and targeted imaging, leaving normal cells unaffected. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Functional cardiac imaging by random access microscopy

    Directory of Open Access Journals (Sweden)

    Claudia eCrocini

    2014-10-01

    Full Text Available Advances in the development of voltage sensitive dyes and Ca2+ sensors in combination with innovative microscopy techniques allowed researchers to perform functional measurements with an unprecedented spatial and temporal resolution. At the moment, one of the shortcomings of available technologies is their incapability of imaging multiple fast phenomena while controlling the biological determinants involved. In the near future, ultrafast deflectors can be used to rapidly scan laser beams across the sample, performing optical measurements of action potential and Ca2+ release from multiple sites within cardiac cells and tissues. The same scanning modality could also be used to control local Ca2+ release and membrane electrical activity by activation of caged compounds and light-gated ion channels. With this approach, local Ca2+ or voltage perturbations could be induced, simulating arrhythmogenic events, and their impact on physiological cell activity could be explored. The development of this optical methodology will provide fundamental insights in cardiac disease, boosting new therapeutic strategies, and, more generally, it will represent a new approach for the investigation of the physiology of excitable cells.

  4. Dye-conjugated single-walled carbon nanotubes induce photothermal therapy under the guidance of near-infrared imaging.

    Science.gov (United States)

    Liang, Xiaoyuan; Shang, Wenting; Chi, Chongwei; Zeng, Chaoting; Wang, Kun; Fang, Chihua; Chen, Qingshan; Liu, Huiyu; Fan, Yingfang; Tian, Jie

    2016-12-28

    Recently, photothermal therapy (PTT) has become viewed as an ideal auxiliary therapeutic treatment for cancers. However, the development of safe, convenient, and highly effective photothermal agents remains a great challenge. In this study, we prepared single-walled carbon nanotubes (SWNTs) for PTT against breast tumors under the guidance of infrared fluorescent cyanines. Tumors were accurately located using near-infrared imaging (NIR) and then exposed to laser irradiation. Both the in vivo and in vitro results showed that the SWNTs have high stability and low cytotoxicity. Introducing polyethylene glycol into our nanoparticles increased the blood-circulation time. Our in vivo results further showed that Cy5.5-conjugated SWNTs mediated PTT, resulting in efficient tumor suppression in mice under the guidance of near-infrared imaging. Due to the small amount of absorption at 808-nm, Cy5.5 increased the efficiency of PTT. Breast tumors significantly shrunk after irradiation under the 808-nm near-infrared laser. The treated mice developed scabs, but otherwise recovered after 15 days, and their physical conditions restored gradually. These data indicate that our unique photothermal-responsive SWNT-Cy5.5-based theranostic agent can serve as a promising candidate for PTT. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  5. Tunable Microfluidic Dye Laser

    DEFF Research Database (Denmark)

    Olsen, Brian Bilenberg; Helbo, Bjarne; Kutter, Jörg Peter

    2003-01-01

    We present a tunable microfluidic dye laser fabricated in SU-8. The tunability is enabled by integrating a microfluidic diffusion mixer with an existing microfluidic dye laser design by Helbo et al. By controlling the relative flows in the mixer between a dye solution and a solvent......, the concentration of dye in the laser cavity can be adjusted, allowing the wavelength to be tuned. Wavelength tuning controlled by the dye concentration was demonstrated with macroscopic dye lasers already in 1971, but this principle only becomes practically applicable by the use of microfluidic mixing...

  6. Benzidine Dyes Action Plan

    Science.gov (United States)

    This Action Plan addresses the use of benzidine-based dyes and benzidine congener-based dyes, both metalized and non-metalized, in products that would result in consumer exposure, such as for use to color textiles.

  7. A novel water-soluble fluorescent polymer based on perylene bisimides dyes: one-pot preparation and its bio-imaging.

    Science.gov (United States)

    Tan, Haijian; Liu, Hongmei; Liu, Yaojun; Duan, Wenfeng; Yi, Xuegang; Wu, Yonggang; Zhao, Hongchi; Bai, Libin

    2016-01-01

    Perylene bisimides dye-based water-soluble fluorescent polymer P3, N,N'-bis(3-amyl)-1-bromo-7-{4'-[3''-(S-poly(N-acryloyl ethylene diamine hydrochloride)-2'''-methyl propionic acid)propionyloxy hexyloxy]phenyl} perylene-3,4:9,10-tetracarboxylic bisimides, was synthesized with polyelectrolyte modification via one-pot reaction (the reduction reaction of trithioester and click reaction between the thiol group and carbon-carbon double bond were simultaneously conducted in one pot with high conversion). One-pot method can overcome the limitation that usual click reaction between thiol and other groups has low conversion because thiol group is subject to rapid oxidation during purification and storage. Chemical, structural, and optical properties of P3 and intermediate products were fully characterized by nuclear magnetic resonance spectroscopy, Fourier transform infrared, gel permeation chromatograph, UV-vis spectra, and fluorescence spectra, respectively. The results revealed that P3 displayed excellent water solubility and not only exhibited red strong fluorescence emission band in water but also had the similar photoluminescent spectra to those of intermediate products (M4 and P2) in chloroform. Allowing for the potential application in biological detection field, cell viability and live cell imaging with the presence of P3 were further investigated with Hela cells. The results showed that P3 had low cytotoxicity with strong intracellular fluorescence entry. Meanwhile, with the augment of concentration of P3 (0-0.500 mg mL(-1)), the cell uptake and accumulation of P3 increased and thereby result in enhancement of the intracellular fluorescence. These experiment results suggested that P3 had enormous potential as a fluorescence probe to be an important component in biological detection field.

  8. Chemistry of Natural Dyes

    Indian Academy of Sciences (India)

    animals have been identified as potentially rich in natural dye contents, and some of them have been used for natural dyeing for quite some time. Various parts of plants like roots, stems, barks, leaves, fruits and seeds may contain colouring matter which can be exploited. Normally natural dyes are extracted from the roots ...

  9. Extraction of dye

    African Journals Online (AJOL)

    The study investigated the effects of different methods of application of selected mordants on dyeing woven cotton with natural dyes from the leaves of ... INTRODUCTION. In Uganda, plants have traditionally been utilized as a source of colorants for dyeing mats, ropes and other home based materials for a long time.

  10. Novel implantable imaging system for enabling simultaneous multiplanar and multipoint analysis for fluorescence potentiometry in the visual cortex.

    Science.gov (United States)

    Kobayashi, Takuma; Motoyama, Mayumi; Masuda, Hiroyuki; Ohta, Yasumi; Haruta, Makito; Noda, Toshihiko; Sasagawa, Kiyotaka; Tokuda, Takashi; Tamura, Hideki; Ishikawa, Yasuyuki; Shiosaka, Sadao; Ohta, Jun

    2012-01-01

    Techniques for fast, noninvasive measurement of neuronal excitability within a broad area will be of major importance for analyzing and understanding neuronal networks and animal behavior in neuroscience field. In this research, a novel implantable imaging system for fluorescence potentiometry was developed using a complementary metal-oxide semiconductor (CMOS) technology, and its application to the analysis of cultured brain slices and the brain of a living mouse is described. A CMOS image sensor, small enough to be implanted into the brain, with light-emitting diodes and an absorbing filter was developed to enable real-time fluorescence imaging. The sensor, in conjunction with a voltage-sensitive dye, was certainly able to visualize the potential statuses of neurons and obtain physiological responses in both right and left visual cortex simultaneously by using multiple sensors for the first time. This accomplished multiplanar and multipoint measurement provides multidimensional information from different aspects. The light microsensors do not disturb the animal behavior. This implies that the imaging system can combine functional fluorescence imaging in the brain with behavioral experiments in a freely moving animal. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Investigation of hair dye deposition, hair color loss, and hair damage during multiple oxidative dyeing and shampooing cycles.

    Science.gov (United States)

    Zhang, Guojin; McMullen, Roger L; Kulcsar, Lidia

    2016-01-01

    Color fastness is a major concern for consumers and manufacturers of oxidative hair dye products. Hair dye loss results from multiple wash cycles in which the hair dye is dissolved by water and leaches from the hair shaft. In this study, we carried out a series of measurements to help us better understand the kinetics of the leaching process and pathways associated with its escape from the fiber. Hair dye leaching kinetics was measured by suspending hair in a dissolution apparatus and monitoring the dye concentration in solution (leached dye) with an ultraviolet-visible spectrophotometer. The physical state of dye deposited in hair fibers was evaluated by a reflectance light microscopy technique, based on image stacking, allowing enhanced depth of field imaging. The dye distribution within the fiber was monitored by infrared spectroscopic imaging of hair fiber cross sections. Damage to the ultrafine structure of the hair cuticle (surface, endocuticle, and cell membrane complex) and cortex (cell membrane complex) was determined in hair cross sections and on the hair fiber surface with atomic force microscopy. Using differential scanning calorimetry, we investigated how consecutive coloring and leaching processes affect the internal proteins of hair. Further, to probe the surface properties of hair we utilized contact angle measurements. This study was conducted on both pigmented and nonpigmented hair to gain insight into the influence of melanin on the hair dye deposition and leaching processes. Both types of hair were colored utilizing a commercial oxidative hair dye product based on pyrazole chemistry.

  12. Toxicology of food dyes.

    Science.gov (United States)

    Kobylewski, Sarah; Jacobson, Michael F

    2012-01-01

    Food dyes, synthesized originally from coal tar and now petroleum, have long been controversial because of safety concerns. Many dyes have been banned because of their adverse effects on laboratory animals or inadequate testing. This review finds that all of the nine currently US-approved dyes raise health concerns of varying degrees. Red 3 causes cancer in animals, and there is evidence that several other dyes also are carcinogenic. Three dyes (Red 40, Yellow 5, and Yellow 6) have been found to be contaminated with benzidine or other carcinogens. At least four dyes (Blue 1, Red 40, Yellow 5, and Yellow 6) cause hypersensitivity reactions. Numerous microbiological and rodent studies of Yellow 5 were positive for genotoxicity. Toxicity tests on two dyes (Citrus Red 2 and Orange B) also suggest safety concerns, but Citrus Red 2 is used at low levels and only on some Florida oranges and Orange B has not been used for several years. The inadequacy of much of the testing and the evidence for carcinogenicity, genotoxicity, and hypersensitivity, coupled with the fact that dyes do not improve the safety or nutritional quality of foods, indicates that all of the currently used dyes should be removed from the food supply and replaced, if at all, by safer colorings. It is recommended that regulatory authorities require better and independent toxicity testing, exercise greater caution regarding continued approval of these dyes, and in the future approve only well-tested, safe dyes.

  13. Hair dye contact allergy

    DEFF Research Database (Denmark)

    Søsted, Heidi; Rastogi, Suresh Chandra; Andersen, Klaus Ejner

    2004-01-01

    Colouring of hair can cause severe allergic contact dermatitis. The most frequently reported hair dye allergens are p-phenylenediamine (PPD) and toluene-2,5-diamine, which are included in, respectively, the patch test standard series and the hairdressers series. The aim of the present study...... was to identify dye precursors and couplers in hair dyeing products causing clinical hair dye dermatitis and to compare the data with the contents of these compounds in a randomly selected set of similar products. The patient material comprised 9 cases of characteristic clinical allergic hair dye reaction, where...... exposure history and patch testing had identified a specific hair dye product as the cause of the reaction. The 9 products used by the patients were subjected to chemical analysis. 8 hair dye products contained toluene-2,5-diamine (0.18 to 0.98%). PPD (0.27%) was found in 1 product, and m-aminophenol (0...

  14. Treatment of dyeing wastewater including reactive dyes (Reactive ...

    African Journals Online (AJOL)

    2013-08-15

    Aug 15, 2013 ... Treatment of dyeing wastewater including reactive dyes. (Reactive Red RB, Reactive Black B, ... Keywords: Rhizopus arrhizus, wastewater treatment, decolourisation, textile dye. INTRODUCTION. Dyeing effluents ... as bacteria, yeasts, algae and fungi, are able to remove differ- ent classes of dyes (Fu and ...

  15. Identification of small-scale low and high permeability layers using single well forced-gradient tracer tests: fluorescent dye imaging and modelling at the laboratory-scale.

    Science.gov (United States)

    Barns, Gareth L; Thornton, Steven F; Wilson, Ryan D

    2015-01-01

    Heterogeneity in aquifer permeability, which creates paths of varying mass flux and spatially complex contaminant plumes, can complicate the interpretation of contaminant fate and transport in groundwater. Identifying the location of high mass flux paths is critical for the reliable estimation of solute transport parameters and design of groundwater remediation schemes. Dipole flow tracer tests (DFTTs) and push-pull tests (PPTs) are single well forced-gradient tests which have been used at field-scale to estimate aquifer hydraulic and transport properties. In this study, the potential for PPTs and DFTTs to resolve the location of layered high- and low-permeability layers in granular porous media was investigated with a pseudo 2-D bench-scale aquifer model. Finite element fate and transport modelling was also undertaken to identify appropriate set-ups for in situ tests to determine the type, magnitude, location and extent of such layered permeability contrasts at the field-scale. The characteristics of flow patterns created during experiments were evaluated using fluorescent dye imaging and compared with the breakthrough behaviour of an inorganic conservative tracer. The experimental results show that tracer breakthrough during PPTs is not sensitive to minor permeability contrasts for conditions where there is no hydraulic gradient. In contrast, DFTTs are sensitive to the type and location of permeability contrasts in the host media and could potentially be used to establish the presence and location of high or low mass flux paths. Numerical modelling shows that the tracer peak breakthrough time and concentration in a DFTT is sensitive to the magnitude of the permeability contrast (defined as the permeability of the layer over the permeability of the bulk media) between values of 0.01-20. DFTTs are shown to be more sensitive to deducing variations in the contrast, location and size of aquifer layered permeability contrasts when a shorter central packer is used

  16. Effects of Single and Blended Coating Pigments on the Inkjet Image Quality of Dye Sublimation Transfer Printed Paper: SiO2, CaCO3, Talc, and Sericite

    Directory of Open Access Journals (Sweden)

    Chi-Ching Lin

    2016-01-01

    Full Text Available In this study, we investigated the effects on the image quality of CaCO3, SiO2, talc, and sericite on coated inkjet paper. The papers serve as dye sublimation transfer paper for printing on fabrics. The brightness, smoothness, and contact angle of the coated papers were evaluated. The papers were then printed with a textile color image evaluation test form, and the imprinted images were evaluated with respect to six criteria of the solid ink density, tone value increase, print contrast, ink trapping, grayness, and hue error. The overall printed image quality was correlated with the smoothness and brightness of the coated paper but showed no correlation with the contact angle. For single-pigment-coated papers, CaCO3 produced paper with the best color difference performance and could be substituted for silica. On the other hand, SiO2 was found to be suitable for blending with talc, calcium carbonate, and sericite, and its combination with these materials generally produced better image qualities than silica alone. Talc and sericite, when blended with silica as composite coating pigments, produced better printed image qualities than those as single-pigment-coated papers. The overall image quality ranking suggests that the best performance was achieved with CaCO3-, SiO2/talc-, CaCO3/SiO2-, SiO2/sericite-, and SiO2-coated papers.

  17. WATERLESS DYEING [REVIEW

    Directory of Open Access Journals (Sweden)

    DEVRENT Nalan

    2015-05-01

    Full Text Available The textile industry is believed to be one of the biggest consumers of water. Water consumption and exhaustion in dyeing textile materials in conventional methods is an important environmental problem. The cost of waste water treatment will cause a prominent problem in the future as it does today. Increasing consideration of ecologic consequences of industrial processes as well as legislation enforcing the avoidance of environmental problems have caused a reorientation of thinking and promoted projects for replacement of conventional technologies. One of these new technologies is dyeing in supercritical fluids. Dyeing with supercritical carbon dioxide is a favourable concept considering the value of water as a natural resource and the cost of waste water treatment. This dyeing method offers many advantages over conventional aqueous dyeing: During this dyeing process no water is used, therefore there is no waste water problem, no other chemicals are required; the carbon dioxide can be recycled; the dystuff which is not adsorbed on the substrate can be collected and reused; The necessary energy consumption in this process is relatively lower than is needed to heat water in conventional methods of dyeing. Due to unnecessary of drying process, it helps to save both energy and time; and dyeing cycle is shorter compared with traditional methods. In addition carbon dioxide is non-toxic and non-flammable. Supercritical fluid, supercritical dyeing, disperse dyestuffs, solid-fluid equilibrium

  18. Standardization of size, shape and internal structure of spinal cord images: comparison of three transformation methods.

    Directory of Open Access Journals (Sweden)

    Yasuhisa Fujiki

    Full Text Available Functional fluorescence imaging has been widely applied to analyze spatio-temporal patterns of cellular dynamics in the brain and spinal cord. However, it is difficult to integrate spatial information obtained from imaging data in specific regions of interest across multiple samples, due to large variability in the size, shape and internal structure of samples. To solve this problem, we attempted to standardize transversely sectioned spinal cord images focusing on the laminar structure in the gray matter. We employed three standardization methods, the affine transformation (AT, the angle-dependent transformation (ADT and the combination of these two methods (AT+ADT. The ADT is a novel non-linear transformation method developed in this study to adjust an individual image onto the template image in the polar coordinate system. We next compared the accuracy of these three standardization methods. We evaluated two indices, i.e., the spatial distribution of pixels that are not categorized to any layer and the error ratio by the leave-one-out cross validation method. In this study, we used neuron-specific marker (NeuN-stained histological images of transversely sectioned cervical spinal cord slices (21 images obtained from 4 rats to create the standard atlas and also to serve for benchmark tests. We found that the AT+ADT outperformed other two methods, though the accuracy of each method varied depending on the layer. This novel image standardization technique would be applicable to optical recording such as voltage-sensitive dye imaging, and will enable statistical evaluations of neural activation across multiple samples.

  19. Oxazine laser dyes

    Science.gov (United States)

    Hammond, Peter R.; Field, George F.

    1992-01-01

    New oxazine compounds useful as dye laser media in solution, are superiior to prior art materials. The oxazine dyes useful when pumped by the 578.2 nm copper line to operate in the 700-800 nm range are described by formula I ##STR1##

  20. Anaerobic azo dye reduction

    NARCIS (Netherlands)

    Zee, van der F.P.

    2002-01-01

    Azo dyes, aromatic moieties linked together by azo (-N=N-) chromophores, represent the largest class of dyes used in textile-processing and other industries. The release of these compounds into the environment is undesirable, not only because of their colour, but also

  1. Novel fluorescent dyes for single DNA molecule techniques.

    Science.gov (United States)

    Zarkov, Alexander; Vasilev, Aleksey; Deligeorgiev, Todor; Stoynov, Stoyno; Nedelcheva-Veleva, Marina

    2013-01-01

    To answer the demands of scientific and medical imaging issues, the family of nucleic acid fluorescent dyes is constantly enlarging. Most of the developed dyes reveal high qualities in bulk solution assays but are inefficient to produce a strong and sufficiently stable signal to enable the application of single-molecule techniques. Therefore, we tested 12 novel monomeric and homodimeric cyanine dyes for potential single DNA molecule imaging. Although their qualities in bulk solutions have already been described, nothing was known about their behavior on a single-molecule level. All 12 dyes demonstrated strong emission when intercalated into single DNA molecules and stretched on a silanized surface, which makes them the perfect choice for fluorescent microscopy imaging. A comparison of their fluorescence intensity and photostability with the most applicable dyes in single-molecule techniques, fluorescent dyes YOYO-1 and POPO-3, was carried out. They all exhibited a strong signal, comparable to that of YOYO-1. However, in contrast to YOYO-1, which is visualized under a green filter only, their emission permits red filter visualization. As their photostability highly exceeds that of similar spectrum POPO-3 dye, the studied dyes stand out as the best choice for a broad range of solid surface single-molecule applications when yellow to red DNA backbone fluorescence is needed.

  2. Novel Fluorescent Dyes for Single DNA Molecule Techniques

    Directory of Open Access Journals (Sweden)

    Alexander Zarkov

    2013-03-01

    Full Text Available To answer the demands of scientific and medical imaging issues, the family of nucleic acid fluorescent dyes is constantly enlarging. Most of the developed dyes reveal high qualities in bulk solution assays but are inefficient to produce a strong and sufficiently stable signal to enable the application of single-molecule techniques. Therefore, we tested 12 novel monomeric and homodimeric cyanine dyes for potential single DNA molecule imaging. Although their qualities in bulk solutions have already been described, nothing was known about their behavior on a single-molecule level. All 12 dyes demonstrated strong emission when intercalated into single DNA molecules and stretched on a silanized surface, which makes them the perfect choice for fluorescent microscopy imaging. A comparison of their fluorescence intensity and photostability with the most applicable dyes in single-molecule techniques, fluorescent dyes YOYO-1 and POPO-3, was carried out. They all exhibited a strong signal, comparable to that of YOYO-1. However, in contrast to YOYO-1, which is visualized under a green filter only, their emission permits red filter visualization. As their photostability highly exceeds that of similar spectrum POPO-3 dye, the studied dyes stand out as the best choice for a broad range of solid surface single-molecule applications when yellow to red DNA backbone fluorescence is needed.

  3. Unsymmetrical Heptamethine Dyes for NIR Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Thomas Geiger

    2014-01-01

    Full Text Available Seven unsymmetrical heptamethine dyes with carboxylic acid functionality were synthesized and characterized. These near-infrared dyes exhibit outstanding photophysical properties depending on their heterocyclic moieties and molecular structure. As proof of principle, the dyes were used as photosensitizers in dye-sensitized solar cells. Using the most promising dye, an overall conversion efficiency of 1.22% and an almost colorless solar cell were achieved.

  4. Dyeing of Polyester with Disperse Dyes: Part 2. Synthesis and Dyeing Characteristics of Some Azo Disperse Dyes for Polyester Fabrics

    Directory of Open Access Journals (Sweden)

    Alya M. Al-Etaibi

    2016-06-01

    Full Text Available The goal of this study was to utilize carrier for accelerating the rate of dyeing not only to enhance dyeing of polyester fabrics dyed with disperse dyes 3a,b, but also to save energy. Both the color strength expressed as dye uptake and the fastness properties of the dyed fabrics were evaluated.

  5. Dyeing of Polyester with Disperse Dyes: Part 2. Synthesis and Dyeing Characteristics of Some Azo Disperse Dyes for Polyester Fabrics.

    Science.gov (United States)

    Al-Etaibi, Alya M; Alnassar, Huda S; El-Apasery, Morsy Ahmed

    2016-06-29

    The goal of this study was to utilize carrier for accelerating the rate of dyeing not only to enhance dyeing of polyester fabrics dyed with disperse dyes 3a,b, but also to save energy. Both the color strength expressed as dye uptake and the fastness properties of the dyed fabrics were evaluated.

  6. Plasmonic Dye-Sensitized Solar Cells

    KAUST Repository

    Ding, I-Kang

    2010-12-14

    This image presents a scanning electron microscopy image of solid state dye-sensitized solar cell with a plasmonic back reflector, overlaid with simulated field intensity plots when monochromatic light is incident on the device. Plasmonic back reflectors, which consist of 2D arrays of silver nanodomes, can enhance absorption through excitation of plasmonic modes and increased light scattering, as reported by Michael D. McGehee, Yi Cui, and co-workers.

  7. Spectrally resolved visualization of fluorescent dyes permeating into skin

    Science.gov (United States)

    Maeder, Ulf; Bergmann, Thorsten; Beer, Sebastian; Burg, Jan Michael; Schmidts, Thomas; Runkel, Frank; Fiebich, Martin

    2012-03-01

    We present a spectrally resolved confocal imaging approach to qualitatively asses the overall uptake and the penetration depth of fluorescent dyes into biological tissue. We use a confocal microscope with a spectral resolution of 5 nm to measure porcine skin tissue after performing a Franz-Diffusion experiment with a submicron emulsion enriched with the fluorescent dye Nile Red. The evaluation uses linear unmixing of the dye and the tissue autofluorescence spectra. The results are combined with a manual segmentation of the skin's epidermis and dermis layers to assess the penetration behavior additionally to the overall uptake. The diffusion experiments, performed for 3h and 24h, show a 3-fold increased dye uptake in the epidermis and dermis for the 24h samples. As the method is based on spectral information it does not face the problem of superimposed dye and tissue spectra and therefore is more precise compared to intensity based evaluation methods.

  8. Multimodal Imaging of Integrin Receptor-Positive Tumors by Bioluminescence, Fluorescence, Gamma Scintigraphy, and Single-Photon Emission Computed Tomography Using a Cyclic RGD Peptide Labeled with a Near-Infrared Fluorescent Dye and a Radionuclide

    Directory of Open Access Journals (Sweden)

    W. Barry Edwards

    2009-03-01

    Full Text Available Integrins, particularly the αvβ3 heterodimers, play important roles in tumor-induced angiogenesis and invasiveness. To image the expression pattern of the αvβ3 integrin in tumors through a multimodality imaging paradigm, we prepared a cyclic RGDyK peptide analogue (LS308 bearing a tetraazamacrocycle 1,4,7,10-tetraazacyclododecane-N, N′, N″, N‴-tetraacetic acid (DOTA and a lipophilic near-infrared (NIR fluorescent dye cypate. The αvβ3 integrin binding affinity and the internalization properties of LS308 mediated by the αvβ3 integrin in 4t1luc cells were investigated by receptor binding assay and fluorescence microscopy, respectively. The in vivo distribution of 111In-labeled LS308 in a 4t1luc tumor-bearing mouse model was studied by fluorescence, bioluminescence, planar gamma, and single-photon emission computed tomography (SPECT. The results show that LS308 has high affinity for αvβ3 integrin and internalized preferentially via the αvβ3 integrin-mediated endocytosis in 4t1luc cells. We also found that LS308 selectively accumulated in αvβ3-positve tumors in a receptor-specific manner and was visualized by the four imaging methods. Whereas the endogenous bioluminescence imaging identified the ensemble of the tumor tissue, the fluorescence and SPECT methods with the exogenous contrast agent LS308 reported the local expression of αvβ3 integrin. Thus, the multimodal imaging approach could provide important complementary diagnostic information for monitoring the efficacy of new antiangiogenic drugs.

  9. Mordant dyes as sensitisers in dye-sensitised solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Millington, Keith R.; Fincher, Keith W.; King, A. Lee [Commonwealth Scientific and Industrial Research Organisation, Textile and Fibre Technology, P.O. Box 21, Belmont, Vic. 3216 (Australia)

    2007-10-15

    Many mordant dyes commonly used in the textile industry form coordination complexes at the surface of nanocrystalline TiO{sub 2}. Dyes having a salicylate chelating group are particularly effective. Forty-nine commercial mordant dyes were studied as sensitisers in a non-optimised dye-sensitised solar cell (DSSC) and their performance compared to the N3 ruthenium complex. Although N3 produced the highest output, six mordant dyes produced photocurrents >0.2 mA. UV-visible spectra of the dye-complexed photoanodes suggest that some mordant dyes are more strongly bound to the TiO{sub 2} surface than N3. Photocatalytic oxidation of these dyes does not appear to occur in a DSSC environment. (author)

  10. Giant magnetoimpedance intrinsic impedance and voltage sensitivity of rapidly solidified Co{sub 66}Fe{sub 2}Cr{sub 4}Si{sub 13}B{sub 15} amorphous wire for highly sensitive sensors applications

    Energy Technology Data Exchange (ETDEWEB)

    Das, Tarun K.; Mandal, Sushil K. [CSIR - National Metallurgical Laboratory, NDE and Magnetic Materials Group, MST Division, Jamshedpur (India); Banerji, Pallab [Indian Institute of Technology, Kharagpur, Materials Science Centre, Kharagpur (India)

    2016-11-15

    We report a systematic study of the influence of wire length, L, dependence of giant magneto-impedance (GMI) sensitivity of Co{sub 66}Fe{sub 2}Cr{sub 4}Si{sub 13}B{sub 15} soft magnetic amorphous wire of diameter ∝ 100 μm developed by in-water quenching technique. The magnetization behaviour (hysteresis loops) of the wire with different length (L = 1, 2, 3, 5, 8 and 10 cm) has been evaluated by fuxmetric induction method. It was observed that the behaviour of the hysteresis loops change drastically with the wire length, being attributed to the existence of a critical length, L{sub C}, found to be around 3 cm. GMI measurements have been taken using automated GMI measurement system and the GMI sensitivities in terms of intrinsic impedance sensitivity (S{sub Ω/Am}{sup -1}) and voltage sensitivity (S{sub V/Am}{sup -1}) of the wire have been evaluated under optimal bias field and excitation current. It was found that the maximum (S{sub Ω/Am}{sup -1}){sub max} ∼ 0.63 Ω/kAm{sup -1}/cm and (S{sub V/Am}{sup -1}){sub max} ∼ 3.10 V/kAm{sup -1}/cm were achieved at a critical length L{sub C} ∝ 3 cm of the wire for an AC current of 5 mA and a frequency of 5 MHz. These findings provide crucial insights for optimization of the geometrical dimensions of magnetic sensing elements and important practical guidance for designing high sensitive GMI sensors. The relevant combinations of magnetic material parameters and operating conditions that optimize the sensitivity are highlighted. (orig.)

  11. Dual pathways of calcium entry in spike and plateau phases of luteinizing hormone release from chicken pituitary cells: sequential activation of receptor-operated and voltage-sensitive calcium channels by gonadotropin-releasing hormone

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, J.S.; Wakefield, I.K.; King, J.A.; Mulligan, G.P.; Millar, R.P.

    1988-04-01

    It has previously been shown that, in pituitary gonadotrope cells, the initial rise in cytosolic Ca2+ induced by GnRH is due to a Ca2+ mobilization from intracellular stores. This raises the possibility that the initial transient spike phase of LH release might be fully or partially independent of extracellular Ca2+. We have therefore characterized the extracellular Ca2+ requirements, and the sensitivity to Ca2+ channel blockers, of the spike and plateau phases of secretion separately. In the absence of extracellular Ca2+ the spike and plateau phases were inhibited by 65 +/- 4% and 106 +/- 3%, respectively. Both phases exhibited a similar dependence on concentration of extracellular Ca2+. However, voltage-sensitive Ca2+ channel blockers D600 and nifedipine had a negligible effect on the spike phase, while inhibiting the plateau phase by approximately 50%. In contrast, ruthenium red, Gd3+ ions, and Co2+ ions inhibited both spike and plateau phases to a similar extent as removal of extracellular Ca2+. A fraction (35 +/- 4%) of spike phase release was resistant to removal of extracellular Ca2+. This fraction was abolished after calcium depletion of the cells by preincubation with EGTA in the presence of calcium ionophore A23187, indicating that it depends on intracellular Ca2+ stores. Neither absence of extracellular Ca2+, nor the presence of ruthenium red or Gd3+ prevented mobilization of 45Ca2+ from intracellular stores by GnRH. We conclude that mobilization of intracellular stored Ca2+ is insufficient by itself to account for full spike phase LH release.

  12. Photostability effect of silica nanoparticles encapsulated fluorescence dye

    Science.gov (United States)

    Ahmad, Atiqah; Zakaria, Nor Dyana; Razak, Khairunisak Abdul

    2017-12-01

    Fluorescence dyes are based on small organic molecules have become of interest in chemical biology and widely used for cell and intracellular imaging. However, fluorescence dyes have limitations such as photo bleaching, poor photochemical stability and has a short Stokes shift. It is less valuable for long-term cell tracking strategies and has very short lifetime. In order to overcome the problems, dye-incorporated nanomaterials become of interest. Nanomaterials encapsulation provides a protection layer around the fluorescence dye which improves the stability of fluorescence dye. In this study, silica nanoparticles encapsulated with 1,1%-dioctadecyl-3,3,3%,3%-tetramethylindocarbocyanine perchlorate (Dil) was successfully synthesised by using micelle entrapment method to investigate the effect of encapsulation of nanoparticles towards the properties of fluorescent dye. The synthesised nanoparticles (SiDil) was characterised by particle size analyser, Transmission Electron Microscopy (TEM), UV-Vis spectrometer and Fluorescent spectrometer. Observation using TEM showed spherical shape of nanoparticles with 53 nm diameter. Monodispersed and well nanoparticles distribution was confirmed by low polydispersity index of 0.063 obtained by particle size analyser. Furthermore, the photoluminescence properties of the SiDil were evaluated and compared with bare Dil dye. Both SiDil and bare Dil was radiated under 200 W of Halogen lamp for 60 minutes and the absorbance intensity was measured using UV-Vis spectrometer. The result showed more stable absorbance intensity for SiDil compared to bare Dil dye, which indicated that Si nanoparticles encapsulation improved the photostability property.

  13. A study of dyes sorption on biobased cryogels

    Energy Technology Data Exchange (ETDEWEB)

    Dobritoiu, Rodica; Patachia, Silvia, E-mail: st.patachia@unitbv.ro

    2013-11-15

    Three types of biopolymers based materials were synthesized and tested as adsorbents for the dyes from aqueous solutions. Blends based on poly (vinyl alcohol) [PVA] and scleroglucan [Scl], cellulose micro-fibres [cel] and zein, respectively, have been prepared by repeated freezing–thawing cycles. Methylene blue [MB] was selected as a model dye in order to evaluate the capacity of the prepared materials to remove the dyes from aqueous solutions. The effects of the initial dye concentration, contact time and the composition of materials on the kinetic and thermodynamic parameters of sorption were discussed. The pseudo-second-order kinetics was found to better fit the experimental data thus being able to consistently predict the amount of dye adsorbed over the entire sorption period. The sorption equilibrium data obey Freundlich isotherm. Sorption capacity was evaluated both by dye solution and cryogel analysis by using VIS spectrometry and image analysis with CIELAB system. The sorption of monomer or aggregated dye molecules was identified and correlated with the type and morphology of the gel. The highest efficiency in MB removal was obtained for Scl/PVA cryogels in 1:9 weight ratio (9.5279 mg/g MB for an initial concentration by 8 × 10{sup −5} mol/L in MB). These materials are suitable as sorbents for the advanced removal of dyes from waste water.

  14. Making cancer visible--Dyes in surgical oncology.

    Science.gov (United States)

    Yap, Kiryu K; Neuhaus, Susan J

    2016-03-01

    Dyes share an intricate relationship with oncology. Dyes can cause cancer as chemical carcinogens, but can also be harnessed against cancer when used as diagnostic and therapeutic agents. Histopathology, imaging, and newer molecular diagnostics all rely on dyes, and their use in sentinel lymph node biopsies and intra-operative imaging has helped drive a paradigm shift in cancer surgery towards minimally-invasive and organ sparing approaches with enhanced resection accuracy. As therapeutic agents, the cytotoxicity of specific dyes can be employed in direct chemo-ablation or in photodynamic therapy. The same agent can have dual functionalities in cancer detection and treatment, in a novel field known as theranostics. This is facilitated by newer generation dyes conjugated with tumour-targeting probes such as antibodies, and these bio-conjugate agents can also incorporate nanotechnology or radio-isotopes. Further advances will be closely aligned with our increasing understanding of molecular oncology, and will form a new generation of cancer detection and treatment agents that promote precision medicine for cancer. Dyes and their roles have evolved and been reinvented, but they remain relevant as ever. This review explores the fascinating history of dyes, and their place in the state-of-the-art of oncology. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  15. Hair Dye and Hair Relaxers

    Science.gov (United States)

    ... Consumers Consumer Information by Audience For Women Hair Dye and Hair Relaxers Share Tweet Linkedin Pin it ... If you have a bad reaction to hair dyes and relaxers, you should: Stop using the product. ...

  16. Cosensitization of Ruthenium–Polypyridyl Dyes with Organic Dyes in Dye-sensitized Solar Cells

    National Research Council Canada - National Science Library

    Numata, Youhei; Zhang, Shufang; Yang, Xudong; Han, Liyuan

    2013-01-01

    Cosensitization, a technique involving sensitization of a metal-oxide semiconductor electrode with two or more different dyes, is a promising strategy to enhance light-harvesting capabilities of dye...

  17. Microfluidic Dye Lasers

    DEFF Research Database (Denmark)

    Kristensen, Anders; Balslev, Søren; Gersborg-Hansen, Morten

    2006-01-01

    A technology for miniaturized, polymer based lasers, suitable for integration with planar waveguides and microfluidic networks is presented. The microfluidic dye laser device consists of a microfluidic channel with an embedded optical resonator. The devices are fabricated in a thin polymer film...

  18. Levitated droplet dye laser

    DEFF Research Database (Denmark)

    Azzouz, H.; Alkafadiji, L.; Balslev, Søren

    2006-01-01

    a high quality optical resonator. Our 750 nL lasing droplets consist of Rhodamine 6G dissolved in ethylene glycol, at a concentration of 0.02 M. The droplets are optically pumped at 532 nm light from a pulsed, frequency doubled Nd:YAG laser, and the dye laser emission is analyzed by a fixed grating...

  19. for aqueous dye lasers

    Indian Academy of Sciences (India)

    2014-02-12

    Feb 12, 2014 ... polar molecule and possesses larger dipole moment at the excited state (S1), and stabi- lizes its energy by interacting with the polar and protic water solvent. The measured fluorescence spectra of RhB dye in ethanol, water and water with CB[7] (molar ratio. 1:5) in the temperature range 279–298 K were ...

  20. (MTT) dye reduction assay.

    African Journals Online (AJOL)

    to inhibit proliferation of HeLa cells was determined using the 3443- dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) dye reduction assay. Extracts from roots of Agathisanthemum bojeri, Synaptolepis kirkii and Zanha africana and the leaf extract of Physalis peruviana at a concentration of 10 pg/ml inhibited cell ...

  1. Real-time, near-infrared fluorescence imaging with an optimized dye/light source/camera combination for surgical guidance of prostate cancer.

    Science.gov (United States)

    Neuman, Brian P; Eifler, John B; Castanares, Mark; Chowdhury, Wasim H; Chen, Ying; Mease, Ronnie C; Ma, Rong; Mukherjee, Amarnath; Lupold, Shawn E; Pomper, Martin G; Rodriguez, Ronald

    2015-02-15

    The prostate-specific membrane antigen (PSMA) is a surface glycoprotein overexpressed on malignant prostate cells, as well as in the neovasculature of many tumors. Recent efforts to target PSMA for imaging prostate cancer rely on suitably functionalized low-molecular-weight agents. YC-27 is a low-molecular-weight, urea-based agent that enables near-infrared (NIR) imaging of PSMA in vivo. We have developed and validated a laparoscopic imaging system (including an optimized light source, LumiNIR) that is capable of imaging small tumor burdens with minimal background fluorescence in real-time laparoscopic extirpative surgery of small prostate tumor xenografts in murine and porcine models. In a mouse model, we demonstrate the feasibility of using real-time NIR laparoscopic imaging to detect and surgically remove PSMA-positive xenografts. We then validate the use of our laparoscopic real-time NIR imaging system in a large animal model. Our novel light source, which is optimized for YC-27, is capable of detecting as little as 12.4 pg/mL of the compound (2.48-pg YC-27 in 200-μL agarose). Finally, in a mouse xenograft model, we demonstrate that the use of real-time NIR imaging can reduce positive surgical margins (PSM). These data indicate that a NIR-emitting fluorophore targeted to PSMA may allow improved surgical treatment of human prostate cancer, reduce the rate of PSMs, and alleviate the need for adjuvant radiotherapy postoperatively. ©2014 American Association for Cancer Research.

  2. Dye laser principles with applications

    CERN Document Server

    Duarte, Frank J; Liao, Peter F; Kelley, Paul

    1990-01-01

    A tutorial introduction to the field of dye lasers, Dye Laser Principles also serves as an up-to-date overview for those using dye lasers as research and industrial tools. A number of the issues discussed in this book are pertinent not only to dye lasers but also to lasers in general. Most of the chapters in the book contain problem sets that expand on the material covered in the chapter.Key Features* Dye lasers are among the most versatile and successful laser sources currently available in use Offering both pulsed and continuous-wave operation and tunable from the near ultraviole

  3. Spectroscopic and light stability behaviour of photographic dyes at oil aqueous interfaces

    CERN Document Server

    Parmar, C K

    2001-01-01

    Azamethine dyes are used in the silver-halide colour photographic process to record the yellow, magenta, and cyan components of an image. Compared with other dye classes, these particular dyes possess short singlet excited state lifetimes and low triplet state quantum yields, making them resilient to destructive photochemistry. However, in normal daylight conditions these dyes are still prone to degradation, which is noticeable after a number of years. This thesis examines the photophysical characteristics of two pyrazolotriazole azamethine (PT) dye isomers in dilute solutions and at oleophilic-aqueous interfaces, and also investigates the role of the large surface-area-to- volume ratio in photographic dispersions in dye fade mechanisms. Conventional fluorescence spectroscopy as well as steady-state and time-resolved evanescent wave-induced fluorescence spectroscopy (EWIFS) have been used as an analytical tool to probe the changes in dye behaviour in oleophilic-aqueous interfacial regions. Studies show that a...

  4. Plantas Tintureiras Dye Plants

    Directory of Open Access Journals (Sweden)

    Maria do Carmo Serrano

    2008-12-01

    Full Text Available Existe uma vasta bibliografia, até ao séc. XVIII, sobre plantas produtoras de corantes naturais, sendo que apenas um número limitado foi utilizado no tingimento de têxteis antigos, devido à capacidade de resistência à lavagem e ao desvanecimento. O cultivo de plantas ou a sua existência no mundo silvestre tiveram uma enorme importância sócio-económica para muitas comunidades espalhadas pelo mundo e pelas intensas trocas comerciais que geraram. A extracção dos corantes era feita a partir de diferentes partes de plantas ou árvores. Nalgumas plantas eram utilizadas as folhas, enquanto noutras se aproveitavam as flores, as raízes, os frutos, troncos ou sementes. Os corantes podiam ser extraídos através de processos complexos que envolviam diversas operações como maceração, destilação, fermentação, decantação, precipitação, filtração, etc. Neste âmbito, são apresentadas algumas das plantas cultivadas em Portugal e em muitos outros países europeus e que foram usadas em tinturaria. Este trabalho pretende ser um contributo para obstar à perda de conhecimentos das condições de cultivo e da forma como se maximizava a produção de corantes.A vast bibliography exists, until the 18th cen-tury, on natural dyes obtained from plants, but only one limited number was used in the dyeing of old textiles, due to capacity of resistance to wash and light fading. The culture of plants or its existence in the wild world had an enormous economical importance for many communities spread for the world, and the intense commercial exchanges that had generated. The extraction of dyes was done from different parts of plants or trees. In some plants was used the leaves, others, only the roots, the fruits, trunks or seeds. The dyes could be extracted through complex processes that involved various operations as maceration, distillation, fermentation, decantation, precipitation, filtration, etc. In this scope, some of the plants cultivated in

  5. Imaging voltage in neurons

    Science.gov (United States)

    Peterka, Darcy S.; Takahashi, Hiroto; Yuste, Rafael

    2011-01-01

    In the last decades, imaging membrane potential has become a fruitful approach to study neural circuits, especially in invertebrate preparations with large, resilient neurons. At the same time, particularly in mammalian preparations, voltage imaging methods suffer from poor signal to noise and secondary side effects, and they fall short of providing single-cell resolution when imaging of the activity of neuronal populations. As an introduction to these techniques, we briefly review different voltage imaging methods (including organic fluorophores, SHG chromophores, genetic indicators, hybrid, nanoparticles and intrinsic approaches), and illustrate some of their applications to neuronal biophysics and mammalian circuit analysis. We discuss their mechanisms of voltage sensitivity, from reorientation, electrochromic or electro-optical phenomena, to interaction among chromophores or membrane scattering, and highlight their advantages and shortcomings, commenting on the outlook for development of novel voltage imaging methods. PMID:21220095

  6. Dye purity and dye standardization for biological staining

    DEFF Research Database (Denmark)

    Lyon, H O

    2002-01-01

    This review starts with a short discussion of what is meant by a pure dye and a brief description of how dyes are produced. A listing of the types of impurities encountered in dyes is made, followed by technical investigations and assessments of dyes and their impurities including methods...... for separating, identifying and assaying dye components. In the second part of the review, descriptions are given of the standardized staining method approach using standard staining methods for assessing stains, and practical responses to stain impurity including commercial quality control, third-party quality...... control and standardization of reagents, protocols and documentation. Finally, reference is made to the current state of affairs in the dye field....

  7. Synthesis of azo pyridone dyes

    Directory of Open Access Journals (Sweden)

    Mijin Dušan Ž.

    2011-01-01

    Full Text Available Over 50% of all colorants which are used nowdays are azo dyes and pigments, and among them arylazo pyridone dyes (and pigments have became of interest in last several decades due to the high molar extinction coefficient, and the medium to high light and wet fastness properties. They find application generally as disperse dyes. The importance of disperse dyes increased in the 1970s and 1980s due to the use of polyester and nylon as the main synthetic fibers. Also, disperse dyes were used rapidly since 1970 in inks for the heat-transfer printing of polyester. The main synthetic route for the preparation of azo dyes is coupling reaction between an aromatic diazo compound and a coupling component. Of all dyes manufactured, about 60% are produced by this reaction. Arylazo pyridone dyes can be prepared from pyridone moiety as a coupling component, where substituent can be on nitrogen, and diazonim salts which can be derived from different substituted anilines or other heterocyclic derivatives. In addition, arylazo dyes containing pyridone ring can be prepared from arylazo diketones or arylazo ketoesters (obtained by coupling β-diketones or β-ketoesters with diazonim salts by condensation with cyanoacetamide. Disazo dyes can be prepared by tetrazotizing a dianiline and coupling it with a pyridone or by diazotizing aniline and coupling it with a dipyridone. Trisazo dyes can be also prepared by diazotizing of aniline and coupling it with a tripyridone or by hexazotizing a trianiline and coupling it with a pyridone. The main goal of this paper is to give a brief review on the synthesis of arylazo pyridone dyes due to the lack of such reviews. In addition, some properties of arylazo pyridone dyes as light fastness and azo-hydrazon tautomerism are disccused.

  8. High-Speed Imaging Reveals Opposing Effects of Chronic Stress and Antidepressants on Neuronal Activity Propagation through the Hippocampal Trisynaptic Circuit

    Directory of Open Access Journals (Sweden)

    Jens eStepan

    2015-11-01

    Full Text Available Antidepressants (ADs are used as first-line treatment for most stress-related psychiatric disorders. The alterations in brain circuit dynamics that can arise from stress exposure and underlie therapeutic actions of ADs remain, however, poorly understood. Here, enabled by a recently developed voltage-sensitive dye imaging assay in mouse brain slices, we examined the impact of chronic stress and concentration-dependent effects of eight clinically used ADs (belonging to different chemical/functional classes on evoked neuronal activity propagations through the hippocampal trisynaptic circuitry (HTC: perforant path - dentate gyrus - area CA3 - area CA1. Exposure of mice to chronic social defeat stress led to markedly weakened activity propagations (HTC-Waves. In contrast, at concentrations in the low micromolar range, all ADs, which were bath applied to slices, caused an amplification of HTC-Waves in CA regions (invariably in area CA1. The fast-acting antidepressant ketamine, the mood stabilizer lithium, and brain-derived neurotrophic factor (BDNF exerted comparable enhancing effects, whereas the antipsychotic haloperidol and the anxiolytic diazepam attenuated HTC-Waves. Collectively, we provide direct experimental evidence that chronic stress can depress neuronal signal flow through the HTC and demonstrate shared opposing effects of ADs. Thus, our study points to a circuit-level mechanism of ADs to counteract stress-induced impairment of hippocampal network function. However, the observed effects of ADs are impossible to depend on enhanced neurogenesis.

  9. Use of a PEG-conjugated bright near-infrared dye for functional imaging of rerouting of tumor lymphatic drainage after sentinel lymph node metastasis.

    Science.gov (United States)

    Proulx, Steven T; Luciani, Paola; Christiansen, Ailsa; Karaman, Sinem; Blum, Katrin S; Rinderknecht, Matthias; Leroux, Jean-Christophe; Detmar, Michael

    2013-07-01

    Tumor lymphangiogenesis promotes metastatic cancer spread to lymph nodes and beyond. However, the potential remodeling and functionality of tumor-draining lymphatic vessels has remained unclear. Thus, we aimed to develop non-invasive imaging methods for repeated quantitative imaging of lymphatic drainage and of contractile collecting lymphatic vessel function in mice, with colloidal near-infrared (NIR) tracers and a custom fluorescence stereomicroscope specially adapted for NIR sensitive imaging. Using these tools, we quantitatively determined pulse rates and valvular function of collecting lymphatic vessels with high resolution. Unexpectedly, we found that tumor-draining lymphatic vessels in a melanoma footpad model initially were dilated but remained functional, despite lower pulse rates. In two independent tumor models, impaired lymphatic function was detected once metastases were present in draining lymph nodes. Importantly, we found that lymphatic dysfunction, induced by metastatic tumor spread to sentinel lymph nodes, can lead to a rerouting of lymphatic flow away from the metastatic lymph node, via collateral lymphatic vessels, to alternate lymph nodes. These findings might have important clinical implications for the procedure of sentinel lymph node mapping that represents the standard of care for determining prognosis and treatment of melanoma and breast cancer patients. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Dyeing fabrics with metals

    Science.gov (United States)

    Kalivas, Georgia

    2002-06-01

    Traditionally, in textile dyeing, metals have been used as mordants or to improve the color produced by a natural or synthetic dye. In biomedical research and clinical diagnostics gold colloids are used as sensitive signals to detect the presence of pathogens. It has been observed that when metals are finely divided, a distinct color may result that is different from the color of the metal in bulk. For example, when gold is finely divided it may appear black, ruby or purple. This can be seen in biomedical research when gold colloids are reduced to micro-particles. Bright color signals are produced by few nanometer-sized particles. Dr. William Todd, a researcher in the Department of Veterinary Science at the Louisiana State University, developed a method of dyeing fabrics with metals. By using a reagent to bond the metal particles deep into the textile fibers and actually making the metal a part of the chemistry of the fiber. The chemicals of the fabric influence the resulting color. The combination of the element itself, the size of the particle, the chemical nature of the particle and the interaction of the metal with the chemistry of the fabric determine the actual hue. By using different elements, reagents, textiles and solvents a broad range of reproducible colors and tones can be created. Metals can also be combined into alloys, which will produce a variety of colors. The students of the ISCC chapter at the Fashion Institute of Technology dyed fabric using Dr. Todd's method and created a presentation of the results. They also did a demonstration of dyeing fabrics with metals.

  11. HYDROXYANTHRAQUINONE DYES FROM PLANTS

    OpenAIRE

    Caro, Yanis; Petit, Thomas; Grondin, Isabelle; Fouillaud, Mireille; Dufossé, Laurent

    2017-01-01

    International audience; In the plant kingdom, numerous pigments have already been identified, but only a minority of them is allowed by legal regulations for textile dyeing, food coloring or cosmetic and pharmaceutics’ manufacturing. Anthraquinones, produced as secondary metabolites in plants, constitute a large structural variety of compounds among the quinone family. Derivatives that contain hydroxyl groups, namely hydroxy-anthraquinones, are colored. They have attracted the attention of ma...

  12. WATERLESS DYEING [REVIEW

    OpenAIRE

    DEVRENT Nalan

    2015-01-01

    The textile industry is believed to be one of the biggest consumers of water. Water consumption and exhaustion in dyeing textile materials in conventional methods is an important environmental problem. The cost of waste water treatment will cause a prominent problem in the future as it does today. Increasing consideration of ecologic consequences of industrial processes as well as legislation enforcing the avoidance of environmental problems have caused a reorientation of thinking and promote...

  13. Cold Pad-Batch dyeing method for cotton fabric dyeing with reactive dyes using ultrasonic energy.

    Science.gov (United States)

    Khatri, Zeeshan; Memon, Muhammad Hanif; Khatri, Awais; Tanwari, Anwaruddin

    2011-11-01

    Reactive dyes are vastly used in dyeing and printing of cotton fibre. These dyes have a distinctive reactive nature due to active groups which form covalent bonds with -OH groups of cotton through substitution and/or addition mechanism. Among many methods used for dyeing cotton with reactive dyes, the Cold Pad Batch (CPB) method is relatively more environment friendly due to high dye fixation and non requirement of thermal energy. The dyed fabric production rate is low due to requirement of at least twelve hours batching time for dye fixation. The proposed CPB method for dyeing cotton involves ultrasonic energy resulting into a one third decrease in batching time. The dyeing of cotton fibre was carried out with CI reactive red 195 and CI reactive black 5 by conventional and ultrasonic (US) method. The study showed that the use of ultrasonic energy not only shortens the batching time but the alkalis concentrations can considerably be reduced. In this case, the colour strength (K/S) and dye fixation (%F) also enhances without any adverse effect on colour fastness of the dyed fabric. The appearance of dyed fibre surface using scanning electron microscope (SEM) showed relative straightening of fibre convolutions and significant swelling of the fibre upon ultrasonic application. The total colour difference values ΔE (CMC) for the proposed method, were found within close proximity to the conventionally dyed sample. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Fluorescent dye imaging of the volume sampled by single well forced-gradient tracer tests evaluated in a laboratory-scale aquifer physical model.

    Science.gov (United States)

    Barns, Gareth L; Wilson, Ryan D; Thornton, Steven F

    2012-02-01

    This study presents a new method to visualise forced-gradient tracer tests in 2-D using a laboratory-scale aquifer physical model. Experiments were designed to investigate the volume of aquifer sampled in vertical dipole flow tracer tests (DFTT) and push-pull tests (PPT), using a miniature monitoring well and straddle packer arrangement equipped with solute injection and recovery chambers. These tests have previously been used to estimate bulk aquifer hydraulic and transport properties for the evaluation of natural attenuation and other remediation approaches. Experiments were performed in a silica glass bead-filled box, using a fluorescent tracer (fluorescein) to deduce conservative solute transport paths. Digital images of fluorescein transport were captured under ultraviolet light and processed to analyse tracer plume geometry and obtain point-concentration breakthrough histories. Inorganic anion mixtures were also used to obtain conventional tracer breakthrough histories. Concentration data from the conservative tracer breakthrough curves was compared with the digital images and a well characterised numerical model. The results show that the peak tracer breakthrough response in dipole flow tracer tests samples a zone of aquifer close to the well screen, while the sampling volume of push-pull tests is limited by the length of the straddle packers used. The effective sampling volume of these single well forced-gradient tests in isotropic conditions can be estimated with simple equations. The experimental approach offers the opportunity to evaluate under controlled conditions the theoretical basis, design and performance of DFTTs and PPTs in porous media in relation to measured flow and transport properties. Copyright © 2011 Elsevier B.V. All rights reserved.

  15. Use of virtual assisted lung mapping (VAL-MAP), a bronchoscopic multispot dye-marking technique using virtual images, for precise navigation of thoracoscopic sublobar lung resection.

    Science.gov (United States)

    Sato, Masaaki; Omasa, Mitsugu; Chen, Fengshi; Sato, Toshihiko; Sonobe, Makoto; Bando, Toru; Date, Hiroshi

    2014-06-01

    We have developed a novel bronchoscopic multiple marking technique to assist resection of hardly palpable lung tumors. Because 3-dimensional virtual images were used and multiple markings made on the lung surface to provide "geometric" information, we termed this technique "virtual assisted lung mapping" (VAL-MAP). The safety and efficacy of VAL-MAP were evaluated. Virtual bronchoscopy was used to select 2 to 4 appropriate bronchial branches for marking. Bronchoscopy was conducted with the patient under local anesthesia. A metal-tip catheter was inserted into a selected bronchus and advanced to the pleura. The location of the catheter tip was fluoroscopically confirmed, and 1 mL of indigo carmine was injected. This procedure was repeated to complete all the planned markings. Post-VAL-MAP computed tomography was used to visualize the localization of the multiple markings on 3-dimensional virtual images, which were used as references in the subsequent operation. Of the 95 marking attempts made for 37 tumors in 30 patients, 88 (92.6%) were identified and contributed to the surgery. No clinically evident complications were associated with the procedure. A total of 15 wedge resections and 18 segmentectomies were thoracoscopically conducted, with a successful resection rate of 100%. Multiple markings of the VAL-MAP were complementary, enabling us to achieve complete resection even when 1 of the markings failed. The markings were visible even on interlobar fissures, at the apex, and on the diaphragm, which conventional percutaneous marking can hardly reach. VAL-MAP was safely conducted with satisfactory outcomes in our early experience. Additional confirmation of its safety and efficacy is necessary. Copyright © 2014 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  16. Natural dyes and dyeing techniques used by craftswomen in the ...

    African Journals Online (AJOL)

    A survey of the plants used by craftswomen in the northern Hhohho region of Swaziland to dye craft materials was conducted. Nineteen plants were identified and details concerning the part of the plant used, the time of year it was harvested and the colour obtained were documented. The techniques used during the dyeing ...

  17. Treatment of dyeing wastewater including reactive dyes (Reactive ...

    African Journals Online (AJOL)

    The decolourisation potential of growing Rhizopus arrhizus fungal strain in liquid medium containing thiamine was investigated for the removal of anionic reactive dyes such as Reactive Red RB (RR), Reactive Black B (RBB) and Remazol Blue (RB) and a cationic basic dye Methylene Blue (MB). To determine the optimal ...

  18. Metal Complex Dyes for Dye-Sensitized Solar Cells: Recent ...

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 9. Metal Complex Dyes for Dye-Sensitized Solar Cells: ... Author Affiliations. N Sekar1 Vishal Y Gehlot. Dyestuff Technology Department Institute of Chemical Technology (Formerly UDCT) Nathalal Parekh Marg Matunga Mumbai 400 019, India.

  19. Dye Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Di Wei

    2010-03-01

    Full Text Available Dye sensitized solar cell (DSSC is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO2, ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed.

  20. Dye solar cell research

    CSIR Research Space (South Africa)

    Cummings, F

    2009-11-01

    Full Text Available Cummings Energy and Processes Materials Science and Manufacturing Council for Scientific and Industrial Research P.O. Box 395 Pretoria 0001, South Africa 27 November 2009 CONTENT head2rightBackground head2rightCSIR Dye Solar Cell Research head2... rightCollaborations and Links © CSIR 2007 www.csir.co.za head2rightAcknowledgements BACKGROUND head2rightSA is dry: Annual rainfall average of 450 mm compared with a world average of 860 mm head2rightOn upside, we have some...

  1. Design and synthesis of polymer-functionalized NIR fluorescent dyes--magnetic nanoparticles for bioimaging.

    Science.gov (United States)

    Yen, Swee Kuan; Jańczewski, Dominik; Lakshmi, Jeeva Lavanya; Dolmanan, Surani Bin; Tripathy, Sudhiranjan; Ho, Vincent H B; Vijayaragavan, Vimalan; Hariharan, Anushya; Padmanabhan, Parasuraman; Bhakoo, Kishore K; Sudhaharan, Thankiah; Ahmed, Sohail; Zhang, Yong; Tamil Selvan, Subramanian

    2013-08-27

    The fluorescent probes having complete spectral separation between absorption and emission spectra (large Stokes shift) are highly useful for solar concentrators and bioimaging. In bioimaging application, NIR fluorescent dyes have a greater advantage in tissue penetration depth compared to visible-emitting organic dyes or inorganic quantum dots. Here we report the design, synthesis, and characterization of an amphiphilic polymer, poly(isobutylene-alt-maleic anhyride)-functionalized near-infrared (NIR) IR-820 dye and its conjugates with iron oxide (Fe3O4) magnetic nanoparticles (MNPs) for optical and magnetic resonance (MR) imaging. Our results demonstrate that the Stokes shift of unmodified dye can be tuned (from ~106 to 208 nm) by the functionalization of the dye with polymer and MNPs. The fabrication of bimodal probes involves (i) the synthesis of NIR fluorescent dye (IR-820 cyanine) functionalized with ethylenediamine linker in high yield, >90%, (ii) polymer conjugation to the functionalized NIR fluorescent dye, and (iii) grafting the polymer-conjugated dyes on iron oxide MNPs. The resulting uniform, small-sized (ca. 6 nm) NIR fluorescent dye-magnetic hybrid nanoparticles (NPs) exhibit a wider emissive range (800-1000 nm) and minimal cytotoxicity. Our preliminary studies demonstrate the potential utility of these NPs in bioimaging by means of direct labeling of cancerous HeLa cells via NIR fluorescence microscopy and good negative contrast enhancement in T2-weighted MR imaging of a murine model.

  2. Diode pumped tunable dye laser

    Science.gov (United States)

    Burdukova, O.; Gorbunkov, M.; Petukhov, V.; Semenov, M.

    2017-03-01

    A wavelength-tunable dye laser pumped by blue laser diodes (λ =445 nm) in a 200 ns pulsed mode has been developed. We used a 3-mirror cavity with transverse excitation and total internal reflection of laser beam in the active element. Tuning curves for 8 dyes in benzyl alcohol were measured in the range of 506-700 nm. Four dyes have their tuning range more than 60 nm, which is comparable to the tuning ranges of other dye lasers pumped by more expensive sources. The output energy obtained at the generation maximum of both DCM and coumarin 540A dyes was approximately 130 nJ while the pump energy was 2400 nJ.

  3. Experimental study of dye removal from industrial wastewater by membrane technologies of reverse osmosis and nanofiltration

    Science.gov (United States)

    2012-01-01

    Currently, biological method has been utilized in the treatment of wastewater -containing synthetic dyes used by textile industries in Iraq. The present work was devoted to study the operating feasibility using reverse osmosis (RO) and nanofiltration (NF) membrane systems as an alternative treatment method of wastewater discharged from Iraqi textile mills. Acid red, reactive black and reactive blue dyes were selected, based on the usage rate in Iraq. Effects of dye concentration, pH of solution, feed temperature, dissolved salts and operating pressure on permeate flux and dye rejection were studied. Results at operating conditions of dye concentration = 65 mg/L, feed temperature = 39°C and pressure = 8 bar showed the final dye removal with RO membrane as 97.2%, 99.58% and 99.9% for acid red, reactive black and reactive blue dyes, respectively. With NF membrane, the final dye removal were as 93.77%, 95.67%, and 97% for red, black and blue dyes, respectively. The presence of salt (particularly NaCl) in the dye solution resulted in a higher color removal with a permeate flux decline. It was confirmed that pH of solution had a positive impact on dye removal while feed temperature showed a different image. A comparison was made between the results of dye removal in biological and membrane methods. The results showed that membrane method had higher removal potential with lower effective cost. The present study indicates that the use of NF membrane in dye removal from the effluent of Iraqi textile mills is promising. PMID:23369335

  4. Experimental study of dye removal from industrial wastewater by membrane technologies of reverse osmosis and nanofiltration

    Directory of Open Access Journals (Sweden)

    Abid Mohammad Fadhil

    2012-12-01

    Full Text Available Abstract Currently, biological method has been utilized in the treatment of wastewater -containing synthetic dyes used by textile industries in Iraq. The present work was devoted to study the operating feasibility using reverse osmosis (RO and nanofiltration (NF membrane systems as an alternative treatment method of wastewater discharged from Iraqi textile mills. Acid red, reactive black and reactive blue dyes were selected, based on the usage rate in Iraq. Effects of dye concentration, pH of solution, feed temperature, dissolved salts and operating pressure on permeate flux and dye rejection were studied. Results at operating conditions of dye concentration = 65 mg/L, feed temperature = 39°C and pressure = 8 bar showed the final dye removal with RO membrane as 97.2%, 99.58% and 99.9% for acid red, reactive black and reactive blue dyes, respectively. With NF membrane, the final dye removal were as 93.77%, 95.67%, and 97% for red, black and blue dyes, respectively. The presence of salt (particularly NaCl in the dye solution resulted in a higher color removal with a permeate flux decline. It was confirmed that pH of solution had a positive impact on dye removal while feed temperature showed a different image. A comparison was made between the results of dye removal in biological and membrane methods. The results showed that membrane method had higher removal potential with lower effective cost. The present study indicates that the use of NF membrane in dye removal from the effluent of Iraqi textile mills is promising.

  5. Experimental Study of Dye Removal from Industrial Wastewater by Membrane Technologies of Reverse Osmosis and Nanofiltration

    Directory of Open Access Journals (Sweden)

    Mohammad Fadhil Abid

    2012-12-01

    Full Text Available Currently, biological method has been utilized in the treatment of wastewater -containing synthetic dyes used by textile industries in Iraq. The present work was devoted to study the operating feasibility using reverse osmosis (RO and nanofiltration (NF membrane systems as an alternative treatment method of wastewater discharged from Iraqi textile mills. Acid red, reactive black and reactive blue dyes were selected, based on the usage rate in Iraq. Effects of dye concentration, pH of solution, feed temperature, dissolved salts and operating pressure on permeate flux and dye rejection were studied. Results at operating conditions of dye concentration?=?65 mg/L, feed temperature?=?39?C and pressure?=?8 bar showed the final dye removal with RO membrane as 97.2%, 99.58% and 99.9% for acid red, reactive black and reactive blue dyes, respectively. With NF membrane, the final dye removal were as 93.77%, 95.67%, and 97% for red, black and blue dyes, respectively. The presence of salt (particularly NaCl in the dye solution resulted in a higher color removal with a permeate flux decline. It was confirmed that pH of solution had a positive impact on dye removal while feed temperature showed a different image. A comparison was made between the results of dye removal in biological and membrane methods. The results showed that membrane method had higher removal potential with lower effective cost. The present study indicates that the use of NF membrane in dye removal from the effluent of Iraqi textile mills is promising.

  6. Quantitative comparison of long-wavelength Alexa Fluor dyes to Cy dyes: fluorescence of the dyes and their bioconjugates.

    Science.gov (United States)

    Berlier, Judith E; Rothe, Anca; Buller, Gayle; Bradford, Jolene; Gray, Diane R; Filanoski, Brian J; Telford, William G; Yue, Stephen; Liu, Jixiang; Cheung, Ching-Ying; Chang, Wesley; Hirsch, James D; Beechem, Joseph M; Haugland, Rosaria P; Haugland, Richard P

    2003-12-01

    Amine-reactive N-hydroxysuccinimidyl esters of Alexa Fluor fluorescent dyes with principal absorption maxima at about 555 nm, 633 nm, 647 nm, 660 nm, 680 nm, 700 nm, and 750 nm were conjugated to antibodies and other selected proteins. These conjugates were compared with spectrally similar protein conjugates of the Cy3, Cy5, Cy5.5, Cy7, DY-630, DY-635, DY-680, and Atto 565 dyes. As N-hydroxysuccinimidyl ester dyes, the Alexa Fluor 555 dye was similar to the Cy3 dye, and the Alexa Fluor 647 dye was similar to the Cy5 dye with respect to absorption maxima, emission maxima, Stokes shifts, and extinction coefficients. However, both Alexa Fluor dyes were significantly more resistant to photobleaching than were their Cy dye counterparts. Absorption spectra of protein conjugates prepared from these dyes showed prominent blue-shifted shoulder peaks for conjugates of the Cy dyes but only minor shoulder peaks for conjugates of the Alexa Fluor dyes. The anomalous peaks, previously observed for protein conjugates of the Cy5 dye, are presumably due to the formation of dye aggregates. Absorption of light by the dye aggregates does not result in fluorescence, thereby diminishing the fluorescence of the conjugates. The Alexa Fluor 555 and the Alexa Fluor 647 dyes in protein conjugates exhibited significantly less of this self-quenching, and therefore the protein conjugates of Alexa Fluor dyes were significantly more fluorescent than those of the Cy dyes, especially at high degrees of labeling. The results from our flow cytometry, immunocytochemistry, and immunohistochemistry experiments demonstrate that protein-conjugated, long-wavelength Alexa Fluor dyes have advantages compared to the Cy dyes and other long-wavelength dyes in typical fluorescence-based cell labeling applications.

  7. In Situ Mapping of the Molecular Arrangement of Amphiphilic Dye Molecules at the TiO 2 Surface of Dye-Sensitized Solar Cells

    KAUST Repository

    Voïtchovsky, Kislon

    2015-05-27

    © 2015 American Chemical Society. Amphiphilic sensitizers are central to the function of dye-sensitized solar cells. It is known that the cell\\'s performance depends on the molecular arrangement and the density of the dye on the semiconductor surface, but a molecular-level picture of the cell-electrolyte interface is still lacking. Here, we present subnanometer in situ atomic force microscopy images of the Z907 dye at the surface of TiO2 in a relevant liquid. Our results reveal changes in the conformation and the lateral arrangement of the dye molecules, depending on their average packing density on the surface. Complementary quantitative measurements on the ensemble of the film are obtained by the quartz-crystal microbalance with dissipation technique. An atomistic picture of the dye coverage-dependent packing, the effectiveness of the hydrophobic alkyl chains as blocking layer, and the solvent accessibility is obtained from molecular dynamics simulations. (Figure Presented).

  8. Heterobifunctional Dyes: Highly Fluorescent Linkers Based on Cyanine Dyes

    OpenAIRE

    Wycisk, Virginia; Achazi, Katharina; Hirsch, Ole; Kuehne, Christian; Dernedde, Jens; Haag, Rainer; Licha, Kai

    2017-01-01

    Abstract Herein, we present a new synthetic route to cyanine?based heterobifunctional dyes and their application as fluorescent linkers between polymers and biomolecules. The synthesized compounds, designed in the visible spectral range, are equipped with two different reactive groups for highly selective conjugation under physiological conditions. By applying indolenine precursors with functionalized benzenes, we achieved water?soluble asymmetric cyanine dyes bearing maleimido and N?hydroxys...

  9. Survery on Actual Conditions of Food Dyes

    OpenAIRE

    佐藤, ひろみ

    1981-01-01

    Many food dyes are widely used as food additives in Japan, and many investigations have been pointed the problems of safety of these food dyes used in Japanese food. There are two types of commercial food dyes, one is synthetic dyes and the other is natural dyes.Recently Japanese food is not stained so colourfully, but it is stained faintly in colour near to natural food by using of mixed synthetic dyes. On their hand, many consumers have a tendency to prefer natural food dyes because they ha...

  10. Optical Biomedical Diagnostics: Sensors with Optical Response Based on Two-Photon Excited Luminescent Dyes for Biomolecules Detection

    Directory of Open Access Journals (Sweden)

    V. M. Yashchuk

    2008-01-01

    Full Text Available The spectral properties of novel styryl dyes developed for the biomacromolecules (such as DNA detection and imaging were investigated. The energy structures of dye molecules were examined. The spectral data prove that dyes aggregate and interact with DNA. The essential increase of the fluorescence intensity of dyes in the presence of DNA was observed. The photostability and phototoxic influence on the DNA of several styryl dyes were studied by analyzing absorption, fluorescence, and phosphorescence spectra of these dyes and dye-DNA systems. Changes of the optical density value of dye-DNA solutions caused by the irradiation were fixed in the DNA and dye absorption wavelength regions. Fluorescence emission of dye-DNA complexes upon two-photon excitation at wavelength 1064 nm with the 20-nanosecond pulsed YAG:Nd3+ laser and at 840 nm with the 90 famtosecond pulsed Ti:sapphire laser was registered. The values of two-photon absorption cross-sections of dye-DNA complexes were evaluated.

  11. Images

    Data.gov (United States)

    National Aeronautics and Space Administration — Images for the website main pages and all configurations. The upload and access points for the other images are: Website Template RSW images BSCW Images HIRENASD...

  12. Natural dyes as photosensitizers for dye-sensitized solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Hao, Sancun; Wu, Jihuai; Huang, Yunfang; Lin, Jianming [Institute of Materials Physical Chemistry, Huaqiao University, Quanzhou, Fujian 362021 (China)

    2006-02-15

    The dye-sensitized solar cells (DSC) were assembled by using natural dyes extracted from black rice, capsicum, erythrina variegata flower, rosa xanthina, and kelp as sensitizers. The I{sub SC} from 1.142mA to 0.225mA, the V{sub OC} from 0.551V to 0.412V, the fill factor from 0.52 to 0.63, and P{sub max} from 58{mu}W to 327{mu}W were obtained from the DSC sensitized with natural dye extracts. In the extracts of natural fruit, leaves and flower chosen, the black rice extract performed the best photosensitized effect, which was due to the better interaction between the carbonyl and hydroxyl groups of anthocyanin molecule on black rice extract and the surface of TiO{sub 2} porous film. The blue-shift of absorption wavelength of the black rice extract in ethanol solution on TiO{sub 2} film and the blue-shift phenomenon from absorption spectrum to photoaction spectrum of DSC sensitized with black rice extract are discussed in the paper. Because of the simple preparation technique, widely available and low cheap cost natural dye as an alternative sensitizer for dye-sensitized solar cell is promising. (author)

  13. Dye-Sensitized Core/Active Shell Upconversion Nanoparticles for Optogenetics and Bioimaging Applications.

    Science.gov (United States)

    Wu, Xiang; Zhang, Yuanwei; Takle, Kendra; Bilsel, Osman; Li, Zhanjun; Lee, Hyungseok; Zhang, Zijiao; Li, Dongsheng; Fan, Wei; Duan, Chunying; Chan, Emory M; Lois, Carlos; Xiang, Yang; Han, Gang

    2016-01-26

    Near-infrared (NIR) dye-sensitized upconversion nanoparticles (UCNPs) can broaden the absorption range and boost upconversion efficiency of UCNPs. Here, we achieved significantly enhanced upconversion luminescence in dye-sensitized core/active shell UCNPs via the doping of ytterbium ions (Yb(3+)) in the UCNP shell, which bridged the energy transfer from the dye to the UCNP core. As a result, we synergized the two most practical upconversion booster effectors (dye-sensitizing and core/shell enhancement) to amplify upconversion efficiency. We demonstrated two biomedical applications using these UCNPs. By using dye-sensitized core/active shell UCNP embedded poly(methyl methacrylate) polymer implantable systems, we successfully shifted the optogenetic neuron excitation window to a biocompatible and deep tissue penetrable 800 nm wavelength. Furthermore, UCNPs were water-solubilized with Pluronic F127 with high upconversion efficiency and can be imaged in a mouse model.

  14. Diffusion dynamics in microfluidic dye lasers

    DEFF Research Database (Denmark)

    Gersborg-Hansen, Morten; Balslev, Søren; Mortensen, Niels Asger

    2007-01-01

    We have investigated the bleaching dynamics that occur in opto-fluidic dye lasers, where the liquid laser dye in a channel is locally bleached due to optical pumping. Our studies suggest that for micro-fluidic devices, the dye bleaching may be compensated through diffusion of dye molecules alone....... By relying on diffusion rather than convection to generate the necessary dye replenishment, our observation potentially allows for a significant simplification of opto-fluidic dye laser device layouts, omitting the need for cumbersome and costly external fluidic handling or on-chip micro-fluidic pumping...

  15. Construction of 3D MR image-based computer models of pathologic hearts, augmented with histology and optical fluorescence imaging to characterize action potential propagation.

    Science.gov (United States)

    Pop, Mihaela; Sermesant, Maxime; Liu, Garry; Relan, Jatin; Mansi, Tommaso; Soong, Alan; Peyrat, Jean-Marc; Truong, Michael V; Fefer, Paul; McVeigh, Elliot R; Delingette, Herve; Dick, Alexander J; Ayache, Nicholas; Wright, Graham A

    2012-02-01

    Cardiac computer models can help us understand and predict the propagation of excitation waves (i.e., action potential, AP) in healthy and pathologic hearts. Our broad aim is to develop accurate 3D MR image-based computer models of electrophysiology in large hearts (translatable to clinical applications) and to validate them experimentally. The specific goals of this paper were to match models with maps of the propagation of optical AP on the epicardial surface using large porcine hearts with scars, estimating several parameters relevant to macroscopic reaction-diffusion electrophysiological models. We used voltage-sensitive dyes to image AP in large porcine hearts with scars (three specimens had chronic myocardial infarct, and three had radiofrequency RF acute scars). We first analyzed the main AP waves' characteristics: duration (APD) and propagation under controlled pacing locations and frequencies as recorded from 2D optical images. We further built 3D MR image-based computer models that have information derived from the optical measures, as well as morphologic MRI data (i.e., myocardial anatomy, fiber directions and scar definition). The scar morphology from MR images was validated against corresponding whole-mount histology. We also compared the measured 3D isochronal maps of depolarization to simulated isochrones (the latter replicating precisely the experimental conditions), performing model customization and 3D volumetric adjustments of the local conductivity. Our results demonstrated that mean APD in the border zone (BZ) of the infarct scars was reduced by ~13% (compared to ~318 ms measured in normal zone, NZ), but APD did not change significantly in the thin BZ of the ablation scars. A generic value for velocity ratio (1:2.7) in healthy myocardial tissue was derived from measured values of transverse and longitudinal conduction velocities relative to fibers direction (22 cm/s and 60 cm/s, respectively). The model customization and 3D volumetric

  16. Laser dye toxicity, hazards, and recommended controls

    Energy Technology Data Exchange (ETDEWEB)

    Mosovsky, J.A.

    1983-05-06

    Laser dyes are complex fluorescent organic compounds which, when in solution with organic solvents, form a lasing medium. The wavelength of a dye laser's output beam can vary with different dyes, concentrations, and solvents, giving it a tunable feature capable of emitting ultraviolet, visible, or infrared radiation. Toxicity information on the approximately 100 commercially available laser dyes is very scarce. Limited animal experimentation has been performed with only a few dyes. This paper summarizes what is known about laser dye toxicity, and offers recommendations for controlling dye hazards. The laser dyes investigated have been categorized according to their central chemical structures. These include the xanthenes (rhodamines and fluoresceins), polymethines (cyanines and carbocyanines), coumarins, and stilbenes. A few other miscellaneous dyes that do not fall into one of these categories have also been investigated. Prepared laser dye solutions usually contain very small quantities of dye--typical dye concentrations are 10/sup -2/ to 10/sup -5/ molar. For this reason, the solvent in which the dye is dissolved plays an important role when defining potential hazards. Practically all the solvents used are flammable and toxic by inhalation and skin absorption, and therefore must be controlled properly.

  17. Fruit based Dye Sensitized Solar Cells

    Science.gov (United States)

    Ung, M. C.; Sipaut, C. S.; Dayou, J.; Liow, K. S.; Kulip, J.; Mansa, R. F.

    2017-07-01

    Dye Sensitized Solar Cell (DSSC) was first discovered in 1991 by O’regan and Gratzel. This new type of solar cell was reported to have lower production cost with efficiency as high as 12% which is comparable to conventional silicon solar cell. Initially, it uses ruthenium dye as light sensitizer for the operation. However, DSSC with ruthenium dyes are facing environment friendly issues due to the toxic chemicals and costly purification in processing ruthenium dye. Regardless of the poor performance in DSSC, natural dyes which are easy to prepare, cheap and environmental friendly still appear to be an alternative as dye sensitizer. In this study, dye sensitized solar cells (DSSCs) were fabricated using anthocyanin source dyes extracted from several local fruits. All the extracts absorb a wide range of the visible light and ultraviolet spectrum. Therefore, all of the natural dyes show light absorption properties which is important for a dye sensitizer. A DSSC is comprised of conductive substrate, nanoporous semiconductor TiO2 layer, dye sensitizer, electrolyte with redox couple and a counter electrode with catalyst. In this study, the effect of different light source and different counter electrode are been investigated. However, it is vital to know that further research need to do more on the locally Borneo sourced dyes to evaluate and enhance their performance in Dye Sensitized Solar Cell.

  18. Fluorescent Polymer Nanoparticles Based on Dyes: Seeking Brighter Tools for Bioimaging

    Science.gov (United States)

    Reisch, Andreas; Klymchenko, Andrey S.

    2017-01-01

    Speed, resolution and sensitivity of today's fluorescence bioimaging can be drastically improved by fluorescent nanoparticles (NPs) that are many-fold brighter than organic dyes and fluorescent proteins. While the field is currently dominated by inorganic NPs, notably quantum dots (QDs), fluorescent polymer NPs encapsulating large quantities of dyes (dye-loaded NPs) have emerged recently as attractive alternative. These new nanomaterials, inspired from the fields of polymeric drug delivery vehicles and advanced fluorophores, can combine superior brightness with biodegradability and low toxicity. Here, we describe the strategies for synthesis of dye-loaded polymer NPs by emulsion polymerization and assembly of pre-formed polymers. Superior brightness requires strong dye loading without aggregation caused quenching (ACQ). Only recently several strategies of dye design were proposed to overcome ACQ in polymer NPs: aggregation induced emission (AIE), dye modification with bulky side groups and use of bulky hydrophobic counterions. The resulting NPs now surpass the brightness of QDs by ~10-fold for comparable size and start reaching the level of the brightest conjugated polymer NPs. Other properties, notably photostability, color, blinking as well as particle size and surface chemistry are also systematically analyzed. Finally, major and emerging applications of dye-loaded NPs for in vitro and in vivo imaging are reviewed. PMID:26901678

  19. Fluorescent Polymer Nanoparticles Based on Dyes: Seeking Brighter Tools for Bioimaging.

    Science.gov (United States)

    Reisch, Andreas; Klymchenko, Andrey S

    2016-04-01

    Speed, resolution and sensitivity of today's fluorescence bioimaging can be drastically improved by fluorescent nanoparticles (NPs) that are many-fold brighter than organic dyes and fluorescent proteins. While the field is currently dominated by inorganic NPs, notably quantum dots (QDs), fluorescent polymer NPs encapsulating large quantities of dyes (dye-loaded NPs) have emerged recently as an attractive alternative. These new nanomaterials, inspired from the fields of polymeric drug delivery vehicles and advanced fluorophores, can combine superior brightness with biodegradability and low toxicity. Here, we describe the strategies for synthesis of dye-loaded polymer NPs by emulsion polymerization and assembly of pre-formed polymers. Superior brightness requires strong dye loading without aggregation-caused quenching (ACQ). Only recently several strategies of dye design were proposed to overcome ACQ in polymer NPs: aggregation induced emission (AIE), dye modification with bulky side groups and use of bulky hydrophobic counterions. The resulting NPs now surpass the brightness of QDs by ≈10-fold for a comparable size, and have started reaching the level of the brightest conjugated polymer NPs. Other properties, notably photostability, color, blinking, as well as particle size and surface chemistry are also systematically analyzed. Finally, major and emerging applications of dye-loaded NPs for in vitro and in vivo imaging are reviewed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. CLARITY-compatible lipophilic dyes for electrode marking and neuronal tracing

    Science.gov (United States)

    Jensen, Kristian H. R.; Berg, Rune W.

    2016-01-01

    Fluorescent lipophilic dyes, such as DiI, stain cellular membranes and are used extensively for retrograde/anterograde labeling of neurons as well as for marking the position of extracellular electrodes after electrophysiology. Convenient histological clearing techniques, such as CLARITY, enable immunostaining and imaging of large volumes for 3D-reconstruction. However, such clearing works by removing lipids and, as an unintended consequence, also removes lipophilic dyes. To remedy this wash-out, the molecular structure of the dye can be altered to adhere to both membranes and proteins so the dye remains in the tissue after lipid–clearing. Nevertheless, the capacity of such modified dyes to remain in tissue has not yet been tested. Here, we test dyes with molecular modifications that make them aldehyde-fixable to proteins. We use three Dil–analogue dyes, CM-DiI, SP-DiI and FM 1–43FX that are modified to be CLARITY-compatible candidates. We use the challenging adult, myelin-rich spinal cord tissue, which requires prolonged lipid–clearing, of rats and mice. All three dyes remained in the tissue after lipid–clearing, but CM-DiI had the sharpest and FM 1–43FX the strongest fluorescent signal. PMID:27597115

  1. Specific tumor labeling enhanced by polyethylene glycol linkage of near infrared dyes conjugated to a chimeric anti-carcinoembryonic antigen antibody in a nude mouse model of human pancreatic cancer

    Science.gov (United States)

    Maawy, Ali A.; Hiroshima, Yukihiko; Zhang, Yong; Luiken, George A.; Hoffman, Robert M.; Bouvet, Michael

    2014-10-01

    Labeling of metastatic tumors can aid in their staging and resection of cancer. Near infrared (NIR) dyes have been used in the clinic for tumor labeling. However, there can be a nonspecific uptake of dye by the liver, lungs, and lymph nodes, which hinders detection of metastasis. In order to overcome these problems, we have used two NIR dyes (DyLight 650 and 750) conjugated to a chimeric anti-carcinoembryonic antigen antibody to evaluate how polyethylene glycol linkage (PEGylation) can improve specific tumor labeling in a nude mouse model of human pancreatic cancer. The conjugated PEGylated and non-PEGylated DyLight 650 and 750 dyes were injected intravenously into non-tumor-bearing nude mice. Serum samples were collected at various time points in order to determine serum concentrations and elimination kinetics. Conjugated PEGylated dyes had significantly higher serum dye concentrations than non-PEGylated dyes (p=0.005 for the 650 dyes and ppancreatic tumors subcutaneously implanted into nude mice were labeled with antibody-dye conjugates and serially imaged. Labeling with conjugated PEGylated dyes resulted in significantly brighter tumors compared to the non-PEGylated dyes (p<0.001 for the 650 dyes; p=0.01 for 750 dyes). PEGylation of the NIR dyes also decreased their accumulation in lymph nodes, liver, and lung. These results demonstrate enhanced selective tumor labeling by PEGylation of dyes conjugated to a tumor-specific antibody, suggesting their future clinical use in fluorescence-guided surgery.

  2. Dye Sensitized Tandem Photovoltaic Cells

    Energy Technology Data Exchange (ETDEWEB)

    Barber, Greg D.

    2009-12-21

    This work provided a new way to look at photoelectrochemical cells and their performance. Although thought of as low efficiency, a the internal efficiency of a 9% global efficiency dye sensitized solar cell is approximately equal to an 18% efficient silicon cell when each is compared to their useful spectral range. Other work undertaken with this contract also reported the first growth oriented titania and perovskite columns on a transparent conducting oxide. Other work has shown than significant performance enhancement in the performance of dye sensitized solar cells can be obtained through the use of coupling inverse opal photonic crystals to the nanocrystalline dye sensitized solar cell. Lastly, a quick efficient method was developed to bond titanium foils to transparent conducting oxide substrates for anodization.

  3. Charged solvatochromic dyes as signal transducers in pH independent fluorescent and colorimetric ion selective nanosensors.

    Science.gov (United States)

    Xie, Xiaojiang; Gutiérrez, Agustín; Trofimov, Valentin; Szilagyi, Istvan; Soldati, Thierry; Bakker, Eric

    2015-10-06

    Ionophore-based ion selective optical nanosensors that operate independently of the sample pH are developed here by the use of electrically charged solvatochromic dyes as signal transducers. A series of dye molecules with a D-π-A structure was synthesized and characterized in various solvents and incorporated into ion selective nanospheres for K(+), Na(+), and H(+). Since dye leakage was greatly suppressed when the solvatochromic dyes were encapsulated in the nanosphere core, ion sensing nanospheres were explored for cellular ion imaging in Dictyostelium discoideum live cells but spontaneous dye loss resulted in undesired staining of cells. The in vitro analysis of potassium in human plasma was successfully demonstrated with this approach. A theoretical model was developed for the response of the ion selective nanosensors containing charged solvatochromic dyes. The nanosensors exhibited a tunable response range, high sensitivity, and good stability.

  4. Optofluidic ring resonator dye lasers

    Science.gov (United States)

    Sun, Yuze; Suter, Jonathan D.; Fan, Xudong

    2010-02-01

    We overview the recent progress on optofluidic ring resonator (OFRR) dye lasers developed in our research group. The fluidics and laser cavity design can be divided into three categories: capillary optofluidic ring resonator (COFRR), integrated cylindrical optofluidic ring resonator (ICOFRR), and coupled optofluidic ring resonator (CpOFRR). The COFRR dye laser is based on a micro-sized glass capillary with a wall thickness of a few micrometers. The capillary circular cross-section forms the ring resonator and supports the whispering gallery modes (WGMs) that interact evanescently with the gain medium in the core. The laser cavity structure is versatile to adapt to the gain medium of any refractive index. Owing to the high Q-factor (>109), the lasing threshold of 25 nJ/mm2 is achieved. Besides directly pump the dye molecules, lasing through fluorescence resonance energy transfer (FRET) between the donor and acceptor dye molecules is also studied in COFRR laser. The energy transfer process can be further controlled by designed DNA scaffold labeled with donor/acceptor molecules. The ICOFRR dye laser is based on a cylindrical ring resonator fused onto the inner surface of a thick walled glass capillary. The structure has robust mechanical strength to sustain rapid gain medium circulation. The CpOFRR utilizes a cylindrical ring resonator fused on the inner surface of the COFRR capillary. Since the capillary wall is thin, the individual WGMs of the cylindrical ring resonator and the COFRR couples strongly and forms Vernier effect, which provides a way to generate a single mode dye laser.

  5. Acid-base indicator properties of dyes from local plants I: dyes from ...

    African Journals Online (AJOL)

    In strong acid/strong base titrations using the dyes as indicators, the end-points obtained agreed well with those obtained using conventional indicators. The dyes were found not suitable for weak acid/weak base titrations. The Ka of the purple dye from Basella alba was of the order of 10-5 while that of the red dye from H.

  6. DecoFungi: a web application for automatic characterisation of dye decolorisation in fungal strains.

    Science.gov (United States)

    Domínguez, César; Heras, Jónathan; Mata, Eloy; Pascual, Vico

    2018-02-27

    Fungi have diverse biotechnological applications in, among others, agriculture, bioenergy generation, or remediation of polluted soil and water. In this context, culture media based on color change in response to degradation of dyes are particularly relevant; but measuring dye decolorisation of fungal strains mainly relies on a visual and semiquantitative classification of color intensity changes. Such a classification is a subjective, time-consuming and difficult to reproduce process. DecoFungi is the first, at least up to the best of our knowledge, application to automatically characterise dye decolorisation level of fungal strains from images of inoculated plates. In order to deal with this task, DecoFungi employs a deep-learning model, accessible through a user-friendly web interface, with an accuracy of 96.5%. DecoFungi is an easy to use system for characterising dye decolorisation level of fungal strains from images of inoculated plates.

  7. A viscosity sensitive fluorescent dye for real-time monitoring of mitochondria transport in neurons.

    Science.gov (United States)

    Baek, Yeonju; Park, Sang Jun; Zhou, Xin; Kim, Gyungmi; Kim, Hwan Myung; Yoon, Juyoung

    2016-12-15

    We present here a viscosity sensitive fluorescent dye, namely thiophene dihemicyanine (TDHC), that enables the specific staining of mitochondria. In comparison to the common mitochondria tracker (Mitotracker Deep Red, MTDR), this dye demonstrated its unique ability for robust staining of mitochondria with high photostability and ultrahigh signal-to-noise ratio (SNR). Moreover, TDHC also showed high sensitivity towards mitochondria membrane potential (ΔΨm) and intramitochondria viscosity change. Consequently, this dye was utilized in real-time monitoring of mitochondria transport in primary cortical neurons. Finally, the Two-Photon Microscopy (TPM) imaging ability of TDHC was also demonstrated. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Dye solubility in supercritical carbon dioxide fluid

    Directory of Open Access Journals (Sweden)

    Yan Jun

    2015-01-01

    Full Text Available Supercritical carbon dioxide fluid is an alternative solvent for the water of the traditional dyeing. The solubility of dyestuff affects greatly the dyeing process. A theoretical model for predicting the dye solubility is proposed and verified experimentally. The paper concludes that the pressure has a greater impact on the dyestuff solubility than temperature, and an optimal dyeing condition is suggested for the highest distribution coefficient of dyestuff.

  9. Effect of dye structure and redox mediators on anaerobic azo and anthraquinone dye reduction

    Directory of Open Access Journals (Sweden)

    Mayara Carantino Costa

    2012-01-01

    Full Text Available We investigated the biological decolourisation of dyes with different molecular structures. The kinetic constant values (k1 achieved with azo dye Reactive Red 120 were 7.6 and 10.1 times higher in the presence of RM (redox mediators AQDS and riboflavin, respectively, than the assays lacking RM. The kinetic constant achieved with the azo dye Congo Red was 42 times higher than that obtained with the anthraquinone dye Reactive Blue 4. The effect of RM on dye reduction was more evident for azo dyes resistant to reductive processes, and ineffective for anthraquinone dyes because of the structural stability of the latter.

  10. Characteristics of nanostructure dye-sensitized solar cells using food dyes

    Science.gov (United States)

    Hosseinnezhad, M.; Rouhani, S.

    2016-01-01

    Dye-sensitized solar cells (DSSCs) were prepared using various food dyes. Food dyes are economically superior to organometallic dyes since they are nontoxic and inexpensive. The spectrophotometric evaluation of chosen food dyes in solution and on a TiO2 substrate show that the dyes form J-aggregation on the photoelectrode substrate. Oxidation of potential measurements for used food dyes ensured an energetically permissible and thermodynamically favorable charge transfer throughout the continuous cycle of a photo-electric conversion. The performance of dye-sensitized solar cells based on food dyes was studied. The results illustrate that the dye containing carboxylic acid and sulfonic acid as the acceptor group gave the maximum conversion efficiency 4.20%.

  11. COLOR POLLUTION CONTROL IN TEXTILE DYEING INDUSTRY ...

    African Journals Online (AJOL)

    a

    The exhausted dye bath wastes still contain significant quantities of coloring matter and impart color to the receiving water bodies. In addition to imparting color dye baths also contribute to organic and inorganic load of the receiving streams. Dye bath wastes are typically characterized by residual color, alkaline pH (mostly), ...

  12. Silicon-substituted Xanthene Dyes and Their Unique Photophysical Properties for Fluorescent Probes.

    Science.gov (United States)

    Ikeno, Takayuki; Nagano, Tetsuo; Hanaoka, Kenjiro

    2017-07-04

    Silicon-substituted xanthene dyes, with Si in place of the O atom at the xanthene 10-position, are practically useful as far-red to near-infrared fluorophores. Many fluorescent probes based on them have recently been reported. These fluorophores retain the advantages of typical xanthene dyes and also show unique properties suitable for applications such as multi-color and super-resolution imaging. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Applying tattoo dye as a third-harmonic generation contrast agent for in vivo optical virtual biopsy of human skin

    Science.gov (United States)

    Tsai, Ming-Rung; Lin, Chen-Yu; Liao, Yi-Hua; Sun, Chi-Kuang

    2013-02-01

    Third-harmonic generation (THG) microscopy has been reported to provide intrinsic contrast in elastic fibers, cytoplasmic membrane, nucleus, actin filaments, lipid bodies, hemoglobin, and melanin in human skin. For advanced molecular imaging, exogenous contrast agents are developed for a higher structural or molecular specificity. We demonstrate the potential of the commonly adopted tattoo dye as a THG contrast agent for in vivo optical biopsy of human skin. Spectroscopy and microscopy experiments were performed on cultured cells with tattoo dyes, in tattooed mouse skin, and in tattooed human skin to demonstrate the THG enhancement effect. Compared with other absorbing dyes or nanoparticles used as exogenous THG contrast agents, tattoo dyes are widely adopted in human skin so that future clinical biocompatibility evaluation is relatively achievable. Combined with the demonstrated THG enhancement effect, tattoo dyes show their promise for future clinical imaging applications.

  14. Highly Fluorescent dye-nanoclay Hybrid Materials Made from Different Dye Classes.

    Science.gov (United States)

    Grabolle, Markus; Starke, Marian; Resch-Genger, Ute

    2016-04-12

    Nanoclays like laponites, which are commercially avaible in large quantities for a very moderate price, provide a facile solubilization strategy for hydrophobic dyes without the need for chemical functionalization and can act as a carrier for a high number of dye molecules. This does not require reactive dyes, amplifies fluorescence signals from individual emitters due to the high number of dyes molecules per laponite disk, and renders hydrophobic emitters applicable in aqueous environments. Aiming at the rational design of bright dye-loaded nanoclays as a new class of fluorescent reporters for bioanalysis and material sciences and the identification of dye structure-property relationships, we screened a series of commercial fluorescent dyes, differing in dye class, charge, and character of the optical transitions involved, and studied the changes of their optical properties caused by clay adsorption at different dye loading concentrations. Upon the basis of our dye loading density-dependent absorption and fluorescence measurements with S2105 and Lumogen F Yellow 083, we could identify two promising dye-nanoclay hybrid materials that reveal high fluorescence quantum yields of the nanoclay-adsorbed dyes of at least 0.20 and low dye self-quenching even at high dye-loading densities of up to 50 dye molecules per laponite platelet.

  15. Waste Water Treatment of Dye Contamination

    OpenAIRE

    Pattana Boonyaprapa

    2009-01-01

    The objectives of this research were to study tie-dye process data and wastewater characteristics from 60 entrepreneurs, and to study the colour density treatment in pilot scale by using upflow anaerobic filters. From 60 filled-out questionnaires, it was found that all tie-dye entrepreneurs used reactive dyes by a hot method. Ninety-eight percent of the tie-dye enterpreneurs produced wastewater at the rate of not more than 1500 liters per day. All of them lacked tie-dye wastewater treatment s...

  16. Contact urticaria to cosmetic and industrial dyes.

    Science.gov (United States)

    Davari, P; Maibach, H I

    2011-01-01

    Contact urticaria (CU) defines the weal-and-flare reaction that occurs after external cutaneous contact with a causative agent. These reactions often cause discomfort for patients, affect their quality of life, and in severe cases may be life-threatening. Some dyes are known to be urticariogens. Many people have daily exposure to these urticariogens, because of the widespread use of dyes, for example in textiles, cosmetics and foods. We reviewed industrial and cosmetic dyes such as hair dyes, basic blue 99 dye, patent blue dyes, henna, red dyes, curcumin and reactive dyes, which can potentially cause CU. Overall, the reported cases of CU lacked appropriate controls. Hair-dye constituents such as preservatives and intensifiers may play an important role as causative agents of CU. We recommend appropriate protection guidelines to reduce the incidence of CU in high-risk groups such as hairdressers, dye-factory workers or workers in dye-related industries. © 2010 The Author(s). Journal compilation © 2010 British Association of Dermatologists.

  17. Anaphylaxis to annatto dye: a case report.

    Science.gov (United States)

    Nish, W A; Whisman, B A; Goetz, D W; Ramirez, D A

    1991-02-01

    Annatto dye is an orange-yellow food coloring extracted from the seeds of the tree Bixa orellana. It is commonly used in cheeses, snack foods, beverages, and cereals. Previously reported adverse reactions associated with annatto dye have included urticaria and angioedema. We present a patient who developed urticaria, angioedema, and severe hypotension within 20 minutes following ingestion of milk and Fiber One cereal, which contained annatto dye. Subsequent skin tests to milk, wheat, and corn were negative. The patient had a strong positive skin test to annatto dye, while controls had no response. The nondialyzable fraction of annatto dye on SDS-PAGE demonstrated two protein staining bands in the range of 50 kD. Immunoblotting demonstrated patient IgE-specific for one of these bands, while controls showed no binding. Annatto dye may contain contaminating or residual seed proteins to which our patient developed IgE hypersensitivity. Annatto dye is a potential rare cause of anaphylaxis.

  18. Interaction between humic acids and anthraquinone dyes

    Energy Technology Data Exchange (ETDEWEB)

    Shinozuka, N.; Lee, C. (The University of Tokyo, Tokyo (Japan). Institute of Industrial Science)

    1991-08-20

    Interactions between humic acids and anthraquinone disperse-dyes were studied. A humic acid extracted from a marine sediment and a commercial one were used to solubilized dyes sparingly soluble in water. The dye solubility in humic acid solution increases with humic acid concentration and enhancement was marked for solution of Aldrich humic acid. The addition of salts decreased the solubility of the dye. But the effects were complicated. Dye solubility increased with temperature. Especially, in the case of a 0.1% solution of marine humic acid at high temperature, the solubility increased. The spectrum of the dye were changed by solubilization in humic acid solution, and a twin peak characteristics of 1,4-isomers of polyaminoanthraquinone disappeared and a broad peak appeared. The dye solubilized by humic acid may thus possibly exist as a solid state as a deposit on quartz. 23 refs., 3 figs., 3 tabs.

  19. Advanced oxidation of acid and reactive dyes

    DEFF Research Database (Denmark)

    Arslan-Alaton, I.; Gursoy, B.H.; Schmidt, Jens Ejbye

    2008-01-01

    The effect of untreated and Fenton-treated acid dyes (C.I. Acid Red 183 and C.I. Acid Orange 51) and a reactive dye (C.I. Reactive Blue 4) on aerobic, anoxic and anaerobic processes was investigated. The optimum Fe2+:H2O2 molar ratio was selected as 1:5 (4:hsp sp="0.25" mM:20:hsp sp="0.25"m...... for the untreated blue, red and orange dyes, respectively. The inhibitory effect of the blue reactive dye on methane production was ∼21% after Fenton treatment. Neither untreated nor treated dyes exhibited an inhibitory effect on denitrification. Aerobic glucose degradation was inhibited by 23-29% by untreated dyes......, whereas Fenton-treated dyes had no inhibitory effect on aerobic glucose degradation....

  20. Enhancement Of Penetrant-Inspection Images

    Science.gov (United States)

    Wilson, Rhonda C.

    1990-01-01

    Proposed computerized video system processes images of fluorescent dyes absorbed in flaws in welds. Video camera, held by operator or by remote manipulator, views weld illuminated by visible white and ultraviolet light. Images of penetrating dye in cracks and voids in weld joint appear on video monitor. Fluorescent features enhanced by software to facilitate identification of true flaws and record important data.

  1. Characteristics of a Broadband Dye Laser Using Pyrromethene and Rhodamine Dyes

    Science.gov (United States)

    Tedder, Sarah A.; Danehy, Paul M.; Wheeler, Jeffrey L.

    2011-01-01

    A broadband dye laser pumped by a frequency-doubled Nd:YAG laser with a full-width half-maximum (FWHM) from 592 to 610 nm was created for the use in a dual-pump broadband CARS system called WIDECARS. The desired broadband dye laser was generated with a mixture of Pyrromethene dyes as an oscillator gain medium and a spectral selective optic in the oscillator cavity. A mixture of Rhodamine dyes were used in the amplifier dye cell. To create this laser a study was performed to characterize the spectral behavior of broadband dye lasers created with Rhodamine dyes 590, 610, and 640, Pyrromethene dyes 597 and 650 as well as mixture of these dyes.

  2. Dyeing of Polyester Woven Fabric with Disperse Dye Using Conventional and Microwave Technique

    Directory of Open Access Journals (Sweden)

    Uzma Syed

    2014-07-01

    Full Text Available Polyester fabric is generally dyed using high temperature dyeing technique and carrier. Both techniques require high energy consumption while few carriers are toxic in nature. In this study, 100% polyester woven fabric was dyed by microwave and conventional dyeing technique with disperse dye; Foron Blue RD GLN by an exhaust method for short dyeing cycle (15 and 30 min. The fabric samples were dyed using conventional high temperature dyeing technique using recommended recipe. Moreover, samples were also dyed using microwave technique with recommended recipe and by the addition of salt and urea, pre-treatment with caustic and organic solvent for improving the dye uptake value and fastness properties. The dyeing assessment; (K/S?max value by Datacolor spectrophotometer, dye uniformity by optical microscope and washing fastness by grey scale were measured. It has been observed that over conventional dyeing method, microwave irradiation dyed sample gives almost 70% high (K/S?max value and uniform dye penetration and good to very good washing fastness property. In addition, microwave dyeing gives excellent dyeing behavior at short dyeing cycle; 15 min; hence saves energy and sustainable dyeing process

  3. Organosilica Nanoparticles with an Intrinsic Secondary Amine: An Efficient and Reusable Adsorbent for Dyes

    Science.gov (United States)

    2017-01-01

    Nanomaterials are promising tools in water remediation because of their large surface area and unique properties compared to bulky materials. We synthesized an organosilica nanoparticle (OSNP) and tuned its composition for anionic dye removal. The adsorption mechanisms are electrostatic attraction and hydrogen bonding between the amine on OSNP and the dye, and the surface charge of the OSNP can be tuned to adsorb either anionic or cationic dyes. Using phenol red as a model dye, we studied the effect of the amine group, pH, ionic strength, time, dye concentration, and nanomaterial mass on the adsorption. The theoretical maximum adsorption capacity was calculated to be 175.44 mg/g (0.47 mmol/g), which is higher than 67 out of 77 reported adsorbents. The experimental maximum adsorption capacity is around 201 mg/g (0.53 mmol/g). Furthermore, the nanoparticles are highly reusable and show stable dye removal and recovery efficiency over at least 10 cycles. In summary, the novel adsorbent system derived from the intrinsic amine group within the frame of OSNP are reusable and tunable for anionic or cationic dyes with high adsorption capacity and fast adsorption. These materials may also have utility in drug delivery or as a carrier for imaging agents. PMID:28422482

  4. APPLICATION OF NATURAL DYES ON TEXTILE: A REVIEW

    OpenAIRE

    Tassew Alemayehu, Zenebesh Teklemariam

    2017-01-01

    This paper reviews the characterization and chemical/biochemical analysis of natural dyes. Extraction of colorants from different natural sources, effects of different mordents and application of binary mixture of natural dyes. Natural dyes are different sources such as plant dyes animal dyes mineral dyes etc. and characteristics of natural dyes such as chemical/biochemical analysis by using UV-visible spectroscopic and chromatographic analysis.

  5. Adsorption Properties of Lac Dyes on Wool, Silk, and Nylon

    OpenAIRE

    Wei, Bo; Chen, Qiu-Yuan; Chen, Guoqiang; Tang, Ren-Cheng; Zhang, Jun

    2013-01-01

    There has been growing interest in the dyeing of textiles with natural dyes. The research about the adsorption properties of natural dyes can help to understand their adsorption mechanism and to control their dyeing process. This study is concerned with the kinetics and isotherms of adsorption of lac dyes on wool, silk, and nylon fibers. It was found that the adsorption kinetics of lac dyes on the three fibers followed the pseudosecond-order kinetic model, and the adsorption rate of lac dyes ...

  6. [Benzidine dyes and risk of bladder cancer].

    Science.gov (United States)

    Miyakawa, M; Yoshida, O

    1989-12-01

    Until the early 1970's there was little concern about dyes which contain benzidine as an integral part of their chemical structure. Furthermore, use of the finished dyes was not considered dangerous. To ascertain whether azo dyes are associated with risk of development of bladder tumors in workers who handpaint Yuzen-type silk kimonos in Kyoto, we investigated the disintegration of dyes to benzidine. In these studies, we found that in rats and mice benzidine-based dyes are metabolized to benzidine and that the azo linkage of benzidine dyes is reduced by Escherichia coli and soil bacteria. These experimental findings were reported previously. In this report, we outline an approach to these studies. Many of the dyes used to color paper, textiles, lipstick, bait used by fishermen, as well as hair dyes, and dyes used in research, for pharmaceutical products, and by defence personnel for the detection of liquid chemical warfare agents, have been shown to be potentially mutagenic or carcinogenic. We review the literature on these dyes.

  7. Synthesis, characterization and dyeing behavior of heterocyclic acid dyes and mordent acid dyes on wool and silk fabrics

    Directory of Open Access Journals (Sweden)

    Patel Hitendra M.

    2012-01-01

    Full Text Available Novel heterocyclic acid and mordent acid dyes were synthesized by the coupling of diazonium salt solution of different aromatic amines with 2- butyl-3-(4-hydroxybenzoylbenzofuran. The resulting heterocyclic acid dyes were characterized by spectral techniques, i.e., elemental analysis, IR, 1HNMR, 13C-NMR spectral studies and UV- visible spectroscopy. The dyeing performance of all the heterocyclic acid dyes was evaluated on wool and silk fabrics. The dyeing of chrome pre treated wool and silk fabrics showed better hues on mordented fabrics. Dyeing of wool and silk fabrics resulted in pinkish blue to red shades with very good depth and levelness. The dyed fabrics showed excellent to very good light, washing, perspiration, sublimation and rubbing fastness.

  8. Cell damage and dye reduction in the quantitative nitroblue tetrazolium (NBT) test.

    Science.gov (United States)

    Segal, A W; Levi, A J

    1975-01-01

    Nitroblue tetrazolium (NBT) is toxic to neutrophils; an effect which is greatly enhanced by endotoxin and latex particles. Cell damage, measured by the release of the cytoplasmic marker enzyme lactate dehydrogenase (LDH), was closely related to dye reduction. This suggests that, in this test, dye reduction occurs largely as a result of contact between intracellular reducing compounds and NBT following damage of the outer cell membrane. The expression of dye reduction as a function of LDH release should enhance the sensitivity of the quantitative NBT test by correcting for the observed intersubject variation in cell damage. The relationship between cell damage and dye reduction is a measure of the reducing capacity of the cell. This was normal in immature, bone marrow neutrophils, but diminished in neutrophils of patients with chronic granulomatous disease. Images Fig. 3 PMID:1212802

  9. Effect of Solvent, Dye-Loading Time, and Dye Choice on the Performance of Dye-Sensitized Solar Cells

    National Research Council Canada - National Science Library

    Rajab, Fahd M

    2016-01-01

    .... The dyes are dissolved in different solvent mixtures, including supercritical carbon dioxide, as well as combinations of more traditional solvents including mixtures of acetonitrile, and t-butanol...

  10. Synthesis and characterization of reactive dye-cassava mesocarp ...

    African Journals Online (AJOL)

    USER

    2010-05-17

    May 17, 2010 ... properties and good dye fixation on the substrate are of importance in the preparation of stable and efficient dye modified cellulosic ion exchange resins. Key words: Reactive dye, dye modified cassava mesocarp, cation exchange resins. INTRODUCTION. Reactive dyes contain functional groups capable of.

  11. Environmentally Friendly Techniques for Wool Dyeing Process

    Directory of Open Access Journals (Sweden)

    Antighin Simona

    2015-11-01

    Full Text Available The aim of this research was to evaluate the influence of dyeing process on the quality of surface waters contaminated with heavy metals and organic compounds, resulted after the wool dyeing process. In order to mark out this aspects an environment friendly method was proposed which involves dyeing wool fiber with new complex combinations derived from a new acid dyes which were complexed, using copper, iron, nickel and zinc salts at 2:1 combination ratio. In order to point out the environmental point of view of wastewaters an experimental protocol was tested by dyeing wool fiber at different pH. Evaluation of complexed combinations impact on the environment involve the following indicators: consumption degree of dyeing solution from the process bath, treatment degree related to the organic content expressed by COD indicator and treatment degree related to the heavy metal concentration respectively.

  12. Azo dyes and human health: A review.

    Science.gov (United States)

    Chung, King-Thom

    2016-10-01

    Synthetic azo dyes are widely used in industries. Gerhardt Domagk discovered that the antimicrobial effect of red azo dye Prontosil was caused by the reductively cleaved (azo reduction) product sulfanilamide. The significance of azo reduction is thus revealed. Azo reduction can be accomplished by human intestinal microflora, skin microflora, environmental microorganisms, to a lesser extent by human liver azoreductase, and by nonbiological means. Some azo dyes can be carcinogenic without being cleaved into aromatic amines. However, the carcinogenicity of many azo dyes is due to their cleaved product such as benzidine. Benzidine induces various human and animal tumors. Another azo dye component, p-phenylenediamine, is a contact allergen. Many azo dyes and their reductively cleaved products as well as chemically related aromatic amines are reported to affect human health, causing allergies and other human maladies.

  13. Increased light harvesting in dye-sensitized solar cells with energy relay dyes

    KAUST Repository

    Hardin, Brian E.

    2009-06-21

    Conventional dye-sensitized solar cells have excellent charge collection efficiencies, high open-circuit voltages and good fill factors. However, dye-sensitized solar cells do not completely absorb all of the photons from the visible and near-infrared domain and consequently have lower short-circuit photocurrent densities than inorganic photovoltaic devices. Here, we present a new design where high-energy photons are absorbed by highly photoluminescent chromophores unattached to the titania and undergo Förster resonant energy transfer to the sensitizing dye. This novel architecture allows for broader spectral absorption, an increase in dye loading, and relaxes the design requirements for the sensitizing dye. We demonstrate a 26% increase in power conversion efficiency when using an energy relay dye (PTCDI) with an organic sensitizing dye (TT1). We estimate the average excitation transfer efficiency in this system to be at least 47%. This system offers a viable pathway to develop more efficient dye-sensitized solar cells.

  14. Stability and efficiency of dye-sensitized solar cells based on papaya-leaf dye

    Science.gov (United States)

    Suyitno, Suyitno; Saputra, Trisma Jaya; Supriyanto, Agus; Arifin, Zainal

    2015-09-01

    The present article reports on the enhancement of the performance and stability of natural dye-based dye-sensitized solar cells (DSSCs). Natural dyes extracted from papaya leaves (PL) were investigated as sensitizers in TiO2-based DSSCs and evaluated in comparison with N719 dye. The acidity of the papaya-leaf extract dyes was tuned by adding benzoic acid. The TiO2 film-coated fluorine-doped tin oxide glass substrates were prepared using the doctor-blade method, followed by sintering at 450 °C. The counter electrode was coated by chemically deposited catalytic platinum. The working electrodes were immersed in N719 dye and papaya dye solutions with concentrations of 8 g/100 mL. The absorbance spectra of the dyes were obtained by ultra-violet-visible spectroscopy. The energy levels of the dyes were measured by the method of cyclic voltammetry. In addition, Fourier transform infrared spectroscopy was used to determine the characteristic functionalities of the dye molecules. The DSSC based on the N719 dye displayed a highest efficiency of 0.87% whereas those based on papaya-leaf dye achieved 0.28% at pH 3.5. The observed improved efficiency of the latter was attributed to the increased current density value. Furthermore, the DSSCs based on papaya-leaf dye with pH 3.5-4 exhibited better stability than those based on N719 dye. However, further studies are required to improve the current density and stability of natural dye-based DSSCs, including the investigation of alternative dye extraction routes, such as isolating the pure chlorophyll from papaya leaves and stabilizing it.

  15. Stability and efficiency of dye-sensitized solar cells based on papaya-leaf dye.

    Science.gov (United States)

    Suyitno, Suyitno; Saputra, Trisma Jaya; Supriyanto, Agus; Arifin, Zainal

    2015-09-05

    The present article reports on the enhancement of the performance and stability of natural dye-based dye-sensitized solar cells (DSSCs). Natural dyes extracted from papaya leaves (PL) were investigated as sensitizers in TiO2-based DSSCs and evaluated in comparison with N719 dye. The acidity of the papaya-leaf extract dyes was tuned by adding benzoic acid. The TiO2 film-coated fluorine-doped tin oxide glass substrates were prepared using the doctor-blade method, followed by sintering at 450 °C. The counter electrode was coated by chemically deposited catalytic platinum. The working electrodes were immersed in N719 dye and papaya dye solutions with concentrations of 8 g/100 mL. The absorbance spectra of the dyes were obtained by ultra-violet-visible spectroscopy. The energy levels of the dyes were measured by the method of cyclic voltammetry. In addition, Fourier transform infrared spectroscopy was used to determine the characteristic functionalities of the dye molecules. The DSSC based on the N719 dye displayed a highest efficiency of 0.87% whereas those based on papaya-leaf dye achieved 0.28% at pH 3.5. The observed improved efficiency of the latter was attributed to the increased current density value. Furthermore, the DSSCs based on papaya-leaf dye with pH 3.5-4 exhibited better stability than those based on N719 dye. However, further studies are required to improve the current density and stability of natural dye-based DSSCs, including the investigation of alternative dye extraction routes, such as isolating the pure chlorophyll from papaya leaves and stabilizing it. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. OPTIMIZATION OF PH AND CONCENTRATION OF DYE LIQUER OF NATURAL DYES

    OpenAIRE

    Shweta Singh* & Dr. Divya Rani Singh

    2017-01-01

    At present research is focused to find out alternative dyes for food and clothing and it should be eco friendly , readly available , cost effective and safe to use both in food material and fabrics. The usage of the plant based natural dyes is traced back to ancient civilization . Due to the environmental and health hazards problems caused by the synthetic dyes.Now people are more concerned about the usage of natural dyes during the last two decades. Botanistists have identified more than...

  17. Photoswitching of monomeric and dimeric DNA-intercalating cyanine dyes for super-resolution microscopy applications.

    Science.gov (United States)

    Flors, Cristina

    2010-05-01

    A growing trend in far-field super resolution fluorescence microscopy based on single molecule photoswitching involves the replacement of photoactivatable fluorophores by common organic dyes in which photoswitching reactions or blinking can be induced. This alternative strategy can greatly simplify the sample preparation and imaging scheme in some cases, and enables its application to a wider range of biological systems. This methodology has been applied successfully to unveil the nanoscale organisation of proteins, but little progress has been seen to date in DNA super-resolution imaging. Previous results have shown that blinking can be induced in the DNA-intercalating dimeric dye YOYO-1 in combination with a reducing buffer, and in turn super-resolution images of DNA can be reconstructed. However, monomeric intercalating dyes like YO-PRO-1 are more advantageous for biological applications. This paper shows that both YO-PRO-1 and YOYO-1 can be used in super-resolution imaging, and different sample preparation strategies are compared in terms of spatial resolution and homogeneity of the reconstructed super-resolution images. Moreover, ensemble and single-molecule experiments provide insight into the switching mechanism. The dyes YOYO-1 and YO-PRO-1 hold great potential for their use in nanoscale imaging of DNA topology in biology and nanoscience.

  18. Using the dye tracer for visualization of preferential flow in macro and micro-scale

    Science.gov (United States)

    Kodesova, Radka; Nemecek, Karel; Kodes, Vit; Fer, Miroslav; Jirku, Veronika; Nikodem, Antonin; Zigova, Anna; Jaksik, Ondrej; Kocarek, Martin

    2010-05-01

    Study is focused on the visualization of the preferential flow in different soil types and their horizons using the dye tracer experiment. Study was performed in the Haplic Luvisol in Hněvčeves and the Haplic Cambisol in Humpolec in the Czech Republic. The 100 (Haplic Luvisol) and 50 (Haplic Cambisol) liters of solute of dye Brilliant Blue FCF (5g/litr) was infiltrated on a 1 x 1 m plot (applying an initial ponding depth of 10 and 5 cm, respectively) immediately after the wheat harvest. On the next day, one half of the plot was sliced horizontally and another half vertically to study the dye distribution within the soil profile to the depth of 100 cm (macro-scale). The 3-D image of the dye distribution was created. In addition, the thin soil sections were made and micromorphological images were used to study a soil aggregate structure and dye distribution in micro-scale. The staining patterns within the vertical and horizontal sections documented very different nature of the preferential flow in different soil types and also within the soil profiles. Images of the Haplic Luvisol showed that while dye tracer was partly regularly transported and only some isolated domains were visible in the surface Ap1 horizon, the preferential flow occurred in the subsurface horizons. The preferential flow in the upper subsurface Ap2 horizon (plow pan) was caused by the gravitational biopores in the very compact matrix structure, which considerably slowed down the dye transport. In the case of deeper horizons (Bt1 and Bt2), the preferential flow occurred due to the gravitational biopores and extensively developed prismatic structure (small and very large aggregates in the Bt1 and Bt2 horizon respectively), which was highly affected by clay coatings. Even better characterization of the preferential flow particularly in these two horizons was obtained, when the same ponding dye infiltration experiment was performed directly on the top of the Bt1 horizon. Images of the Haplic

  19. Voltage sensitive calcium channels (VSCC) in cultured neuronal hybrid cells

    Energy Technology Data Exchange (ETDEWEB)

    Richard, C.L.; U' Prichard, D.C.; Noronha-Blob, L.

    1986-03-01

    Calcium entry via VSCC has been identified in selected, neuronal clonal cell lines using /sup 45/Ca uptake and the fluorescent calcium indicator, quin 2. VSCC in NG108-15 hybrid cells, differentiated with dibutyryl cyclic AMP (1 mM, 4 days) have been further characterized. Depolarization (50 mM K/sup +/, dp) resulted in a rapid (15 sec) influx of Ca/sup 2 +/. Intracellular calcium concentrations were elevated approx. 3 fold from 223 +- 68 nM to 666 +- 74 nM. Dp-sensitive calcium entry was voltage dependent, independent of Na/sup +/, stimulated (40%) by the agonist Bay K 8644 (1..mu..M) and blocked by divalent cations (..mu..M range) and organic calcium channel antagonists (nM range) Bay K 8644, in the absence of KCl, failed to stimulate Ca/sup 2 +/ influx. Tetrodotoxin (TTX) and tetraethylammonium had no effect on VSCC activity. Blockage of VSCC by nimodipine was reversed by increasing Ca/sup 2 +/ ions. IC/sub 50/ values were right shifted from 6.5 nM (1mM/sup 0/Ca/sup 2 +/) to 840 nM (10 mM Ca/sup 2 +/). Ca/sup 2 +/ entry was also stimulated by veratridine (VE), in a Na/sup +//sub 0/-sensitive manner. VE-induced Ca/sup 2 +/ entry was voltage-independent, TTX-sensitive, and was only 25% of dp-sensitive Ca/sup 2 +/ entry. These results together indicate that VSCC in neuronal cells offer a useful system for studying ion channel regulation.

  20. Solvent-free fluidic organic dye lasers.

    Science.gov (United States)

    Choi, Eun Young; Mager, Loic; Cham, Tran Thi; Dorkenoo, Kokou D; Fort, Alain; Wu, Jeong Weon; Barsella, Alberto; Ribierre, Jean-Charles

    2013-05-06

    We report on the demonstration of liquid organic dye lasers based on 9-(2-ethylhexyl)carbazole (EHCz), so-called liquid carbazole, doped with green- and red-emitting laser dyes. Both waveguide and Fabry-Perot type microcavity fluidic organic dye lasers were prepared by capillary action under solvent-free conditions. Cascade Förster-type energy transfer processes from liquid carbazole to laser dyes were employed to achieve color-variable amplified spontaneous emission and lasing. Overall, this study provides the first step towards the development of solvent-free fluidic organic semiconducting lasers and demonstrates a new kind of optoelectronic applications for liquid organic semiconductors.

  1. Solubilization of Hydrophobic Dyes in Surfactant Solutions

    Directory of Open Access Journals (Sweden)

    Ali Reza Tehrani-Bagha

    2013-02-01

    Full Text Available In this paper, the use of surfactants for solubilization of hydrophobic organic dyes (mainly solvent and disperse dyes has been reviewed. The effect of parameters such as the chemical structures of the surfactant and the dye, addition of salt and of polyelectrolytes, pH, and temperature on dye solubilization has been discussed. Surfactant self-assemble into micelles in aqueous solution and below the concentration where this occurs—the critical micelle concentration (CMC—there is no solubilization. Above the CMC, the amount of solubilized dye increases linearly with the increase in surfactant concentration. It is demonstrated that different surfactants work best for different dyes. In general, nonionic surfactants have higher solubilization power than anionic and cationic surfactants. It is likely that the reason for the good performance of nonionic surfactants is that they allow dyes to be accommodated not only in the inner, hydrocarbon part of the micelle but also in the headgroup shell. It is demonstrated that the location of a dye in a surfactant micelle can be assessed from the absorption spectrum of the dye-containing micellar solution.

  2. Metal peroxide- polymer composites for dye degradation

    Science.gov (United States)

    Anshu, Ashwini; Vijayaraghavan, R.

    2017-11-01

    Semiconductor metal oxides/its composites with polymers have been explored for dye degradation through photocatalytic mechanism; these require UV or visible light for activation. Hence, there is need to develop (photo) catalyst that work in absence/presence of light. Towards this objective we are exploring metal peroxides and its composites for dye degradation. Here, we report our work on magnesium peroxide and its composites for dye degradation by photochemical pathways. The nanocomposites are synthesized from monomers and peroxides. The synthesized composites have been characterized by IR, DRS and powder XRD. The composites did not degrade dyes in dark.

  3. Tunable Optofluidic Third Order DFB Dye Laser

    DEFF Research Database (Denmark)

    Gersborg-Hansen, Morten; Kristensen, Anders

    2007-01-01

    We present a low-threshold polymer-based nanofluidic dye laser. By employing a third order DFB laser resonator, we demonstrate a threshold fluence of ~7 muJ/mm2 and a tunability of 45 nm using a single laser dye......We present a low-threshold polymer-based nanofluidic dye laser. By employing a third order DFB laser resonator, we demonstrate a threshold fluence of ~7 muJ/mm2 and a tunability of 45 nm using a single laser dye...

  4. Release Control of Dye from Agar Ball

    OpenAIRE

    板屋, 智之; 山村, 俊貴; 唐澤, 有太朗

    2013-01-01

    Agar is a special product of Nagano prefecture. To utilize agar gel as adsorbing or releasing material of dyes or drugs, spherical agar gel “agar ball” was prepared by dropping aqueous agar solution into salad oil. And releasing behavior of a dye (rhodamine B) from agar ball was studied. The dye is released easily from agar ball, but the release can be controlled by hybiridazation of agar and galatin. In addition, it was found that agar ball could extract the dye from oil phase containing the...

  5. Estimation of Fluorescent Dye Amount in Tracer Dye Test

    Science.gov (United States)

    Pekkan, Emrah; Balkan, Erman; Balkan, Emir

    2015-04-01

    Karstic groundwater is more influenced by human than the groundwater that disperse in pores. On the other hand karstic groundwater resources, in addition to providing agricultural needs, livestock breeding, drinking and domestic water in most of the months of the year, they also supply drinking water to the wild life at high altitudes. Therefore sustainability and hydrogeological investigation of karstic resources is critical. Tracing techniques are widely used in hydrologic and hydrogeologic studies to determine water storage, flow rate, direction and protection area of groundwater resources. Karanfil Mountain (2800 m), located in Adana, Turkey, is one of the karstic recharge areas of the natural springs spread around its periphery. During explorations of the caves of Karanfil mountain, a 600 m deep cave was found by the Turkish and Polish cavers. At the bottom of the cave there is an underground river with a flow rate of approximately 0.5 m3/s during August 2014. The main spring is located 8 km far from the cave's entrance and its mean flow rate changes between 3.4 m3/s and 0.21 m3/s in March and September respectively according to a flowrate observation station of Directorate of Water Works of Turkey. As such frequent storms, snowmelt and normal seasonal variations in rainfall have a significant and rapid effect on the volume of this main spring resource. The objective of our research is to determine and estimate dye amount before its application on the field inspired from the previously literature on the subject. This estimation is intended to provide a preliminary application of a tracer test of a karstic system. In this study dye injection, inlet point will be an underground river located inside the cave and the observation station will be the spring that is approximately 8 km far from the cave entrance. On the other hand there is 600 meter elevation difference between cave entrance and outlet spring. In this test Rodamin-WT will be used as tracer and the

  6. Dataset on analysis of dyeing property of natural dye from Thespesia populnea bark on different fabrics

    Directory of Open Access Journals (Sweden)

    Kuchekar Mohini

    2018-02-01

    Full Text Available The natural dyes separated from plants are of gaining interest as substitutes for synthetic dyes in food and cosmetics. Thespesia populnea (T. populnea is widely grown plant and used in the treatment of various diseases. This study was aimed to separate natural dye from T. populnea bark and analysis of its dyeing property on different fabrics. In this investigation pharmacognostic study was carried out. The pharmacognostic study includes morphological study, microscopical examination, proximate analysis along with the phytochemical study. The dyeing of different fabric was done with a natural dye extracted from T. populnea bark. The fabrics like cotton, butter crep, polymer, chiken, lone, ulene and tarakasa were dye with plant extract. The various evaluation parameters were studied. It includes effect of washing with water, effect of soap, effect of sunlight, effect of alum, effect of Cupric sulphate, microscopical study of fabrics and visual analysis of dyeing by common people were studied. In results, natural dye isolated from T. populnea bark could be used for dyeing fabrics with good fastness properties. The studies reveals that, the dyeing property of fabrics after washing with water and soap, exposed to sunlight does not get affected. It was observed that cotton and tarakasa stains better as compared with other fabrics. It was concluded that the ethanolic extract having good dyeing property.

  7. Photostability of low cost dye-sensitized solar cells based on natural and synthetic dyes.

    Science.gov (United States)

    Abdou, E M; Hafez, H S; Bakir, E; Abdel-Mottaleb, M S A

    2013-11-01

    This paper deals with the use of some natural pigments as well as synthetic dyes to act as sensitizers in dye-sensitized solar cells (DSSCs). Anthocyanin dye extracted from rosella (Hibiscus sabdariffa L.) flowers, the commercially available textile dye Remazole Red RB-133 (RR) and merocyanin-like dye based on 7-methyl coumarin are tested. The photostability of the three dyes is investigated under UV-Vis light exposure. The results show a relatively high stability of the three dyes. Moreover, the photostability of the solid dyes is studied over the TiO2 film electrodes. A very low decolorization rates are recorded as; rate constants k=1.6, 2.1 and 1.9×10(-3)min(-1) for anthocyanin, RR and coumarin dyes, respectively. The stability results favor selecting anthocyanin as a promising sensitizer candidate in DSSCs based on natural products. Dyes-sensitized solar cells are fabricated and their conversion efficiency (η) is 0.27%, 0.14% and 0.001% for the anthocyanin, RR and coumarin dyes, respectively. Moreover, stability tests of the sealed cells based on anthocyanin and RR dyes are done under continuous light exposure of 100mWcm(-2), reveals highly stable DSSCs. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Photostability of low cost dye-sensitized solar cells based on natural and synthetic dyes

    Science.gov (United States)

    Abdou, E. M.; Hafez, H. S.; Bakir, E.; Abdel-Mottaleb, M. S. A.

    2013-11-01

    This paper deals with the use of some natural pigments as well as synthetic dyes to act as sensitizers in dye-sensitized solar cells (DSSCs). Anthocyanin dye extracted from rosella (Hibiscus sabdariffa L.) flowers, the commercially available textile dye Remazole Red RB-133 (RR) and merocyanin-like dye based on 7-methyl coumarin are tested. The photostability of the three dyes is investigated under UV-Vis light exposure. The results show a relatively high stability of the three dyes. Moreover, the photostability of the solid dyes is studied over the TiO2 film electrodes. A very low decolorization rates are recorded as; rate constants k = 1.6, 2.1 and 1.9 × 10-3 min-1 for anthocyanin, RR and coumarin dyes, respectively. The stability results favor selecting anthocyanin as a promising sensitizer candidate in DSSCs based on natural products. Dyes-sensitized solar cells are fabricated and their conversion efficiency (η) is 0.27%, 0.14% and 0.001% for the anthocyanin, RR and coumarin dyes, respectively. Moreover, stability tests of the sealed cells based on anthocyanin and RR dyes are done under continuous light exposure of 100 mW cm-2, reveals highly stable DSSCs.

  9. Dye Sensitized Solar Cell, DSSC

    Directory of Open Access Journals (Sweden)

    Pongsatorn Amornpitoksuk

    2003-07-01

    Full Text Available A dye sensitized solar cell is a new type of solar cell. The operating system of this solar cell type is similar to plant’s photosynthesis process. The sensitizer is available for absorption light and transfer electrons to nanocrystalline metal oxide semiconductor. The ruthenium(II complexes with polypyridyl ligands are usually used as the sensitizers in solar cell. At the present time, the complex of [Ru(2,2',2'’-(COOH3- terpy(NCS3] is the most efficient sensitizer. The total photon to current conversion efficiency was approximately 10% at AM = 1.5.

  10. Incorporating Multiple Energy Relay Dyes in Liquid Dye-Sensitized Solar Cells

    KAUST Repository

    Yum, Jun-Ho

    2011-01-05

    Panchromatic response is essential to increase the light-harvesting efficiency in solar conversion systems. Herein we show increased light harvesting from using multiple energy relay dyes inside dye-sensitized solar cells. Additional photoresponse from 400-590 nm matching the optical window of the zinc phthalocyanine sensitizer was observed due to Förster resonance energy transfer (FRET) from the two energy relay dyes to the sensitizing dye. The complementary absorption spectra of the energy relay dyes and high excitation transfer efficiencies result in a 35% increase in photovoltaic performance. © 2011 Wiley-VCH Verlag GmbH& Co. KGaA.

  11. Metal oxide-encapsulated dye-sensitized photoanodes for dye-sensitized solar cells

    Science.gov (United States)

    Hupp, Joseph T.; Son, Ho-Jin

    2016-01-12

    Dye-sensitized semiconducting metal oxide films for photoanodes, photoanodes incorporating the films and DSCs incorporating the photoanodes are provided. Also provided are methods for making the dye sensitized semiconducting metal oxide films. The methods of making the films are based on the deposition of an encapsulating layer of a semiconducting metal oxide around the molecular anchoring groups of photosensitizing dye molecules adsorbed to a porous film of the semiconducting metal oxide. The encapsulating layer of semiconducting metal oxide is formed in such a way that it is not coated over the chromophores of the adsorbed dye molecules and, therefore, allows the dye molecules to remain electrochemically addressable.

  12. Dye surface coating enables visible light activation of TiO2 nanoparticles leading to degradation of neighboring biological structures.

    Science.gov (United States)

    Blatnik, Jay; Luebke, Lanette; Simonet, Stephanie; Nelson, Megan; Price, Race; Leek, Rachael; Zeng, Leyong; Wu, Aiguo; Brown, Eric

    2012-02-01

    Biologically and chemically modified nanoparticles are gaining much attention as a new tool in cancer detection and treatment. Herein, we demonstrate that an alizarin red S (ARS) dye coating on TiO2 nanoparticles enables visible light activation of the nanoparticles leading to degradation of neighboring biological structures through localized production of reactive oxygen species. Successful coating of nanoparticles with dye is demonstrated through sedimentation, spectrophotometry, and gel electrophoresis techniques. Using gel electrophoresis, we demonstrate that visible light activation of dye-TiO2 nanoparticles leads to degradation of plasmid DNA in vitro. Alterations in integrity and distribution of nuclear membrane associated proteins were detected via fluorescence confocal microscopy in HeLa cells exposed to perinuclear localized ARS-TiO2 nanoparticles that were photoactivated with visible light. This study expands upon previous studies that indicated dye coatings on TiO2 nanoparticles can serve to enhance imaging, by clearly showing that dye coatings on TiO2 nanoparticles can also enhance the photoreactivity of TiO2 nanoparticles by allowing visible light activation. The findings of our study suggest a therapeutic application of dye-coated TiO2 nanoparticles in cancer research; however, at the same time they may reveal limitations on the use of dye assisted visualization of TiO2 nanoparticles in live-cell imaging.

  13. Characterization of Natural Dyes and Traditional Korean Silk Fabric by Surface Analytical Techniques

    Science.gov (United States)

    Lee, Jihye; Kang, Min Hwa; Lee, Kang-Bong; Lee, Yeonhee

    2013-01-01

    Time-of-flight secondary ion mass spectrometry (TOF-SIMS) and X-ray photoelectron spectroscopy (XPS) are well established surface techniques that provide both elemental and organic information from several monolayers of a sample surface, while also allowing depth profiling or image mapping to be carried out. The static TOF-SIMS with improved performances has expanded the application of TOF-SIMS to the study of a variety of organic, polymeric and biological materials. In this work, TOF-SIMS, XPS and Fourier Transform Infrared (FTIR) measurements were used to characterize commercial natural dyes and traditional silk fabric dyed with plant extracts dyes avoiding the time-consuming and destructive extraction procedures necessary for the spectrophotometric and chromatographic methods previously used. Silk textiles dyed with plant extracts were then analyzed for chemical and functional group identification of their dye components and mordants. TOF-SIMS spectra for the dyed silk fabric showed element ions from metallic mordants, specific fragment ions and molecular ions from plant-extracted dyes. The results of TOF-SIMS, XPS and FTIR are very useful as a reference database for comparison with data about traditional Korean silk fabric and to provide an understanding of traditional dyeing materials. Therefore, this study shows that surface techniques are useful for micro-destructive analysis of plant-extracted dyes and Korean dyed silk fabric. PMID:28809257

  14. Characterization of Natural Dyes and Traditional Korean Silk Fabric by Surface Analytical Techniques

    Directory of Open Access Journals (Sweden)

    Yeonhee Lee

    2013-05-01

    Full Text Available Time-of-flight secondary ion mass spectrometry (TOF-SIMS and X-ray photoelectron spectroscopy (XPS are well established surface techniques that provide both elemental and organic information from several monolayers of a sample surface, while also allowing depth profiling or image mapping to be carried out. The static TOF-SIMS with improved performances has expanded the application of TOF-SIMS to the study of a variety of organic, polymeric and biological materials. In this work, TOF-SIMS, XPS and Fourier Transform Infrared (FTIR measurements were used to characterize commercial natural dyes and traditional silk fabric dyed with plant extracts dyes avoiding the time-consuming and destructive extraction procedures necessary for the spectrophotometric and chromatographic methods previously used. Silk textiles dyed with plant extracts were then analyzed for chemical and functional group identification of their dye components and mordants. TOF-SIMS spectra for the dyed silk fabric showed element ions from metallic mordants, specific fragment ions and molecular ions from plant-extracted dyes. The results of TOF-SIMS, XPS and FTIR are very useful as a reference database for comparison with data about traditional Korean silk fabric and to provide an understanding of traditional dyeing materials. Therefore, this study shows that surface techniques are useful for micro-destructive analysis of plant-extracted dyes and Korean dyed silk fabric.

  15. Optical study of xanthene-type dyes in nano-confined liquid

    Science.gov (United States)

    Mahdi Shavakandi, Seyyed; Alizadeh, Khalil; Sharifi, Soheil; Marti, Othmar; Amirkhani, Masoud

    2017-04-01

    The optical activity of dye molecules in different environments is of great interest for many applications such as laser system or biological imaging. We investigate the fluorescence and absorption spectrum of nano-confined xanthene dyes (RhB and fluorescein sodium salt) in a two-phase liquid. Each show very distinct optical behavior in the water phase of a reverse microemulsion. Their optical properties such as absorption and fluorescence for different concentrations of dye and nanodroplets are investigated. We show that for the same concentration of dye in the microemulsion the peak of fluorescence intensity is varied by altering the concentration of nanodroplets. However, the trend of the change is widely different depending on the hydrophobicity of dyes. Quantum-mechanical second order perturbation theory is used to calculate the ratio of dipole moments in the ground and excited states, which accounts for the Stokes shift in fluorescence peak. Photon correlation spectroscopy is employed to check the trace of the dye in the oil phase of the microemulsion.

  16. Simultaneous dyeing and antibacterial finishing for cotton cellulose using a new reactive dye.

    Science.gov (United States)

    Farouk, R; Gaffer, H E

    2013-08-14

    Simultaneous dyeing and antibacterial finishing for cotton fabric using a new antibacterial reactive dye having a modified chemical structure to the commercial reactive dye CI Reactive Red 198 were studied. This modification was carried out by replacing metanilic acid in the commercial dye with 4-amino-N-(4,6-dimethylpyrimidin-2-yl)benzenesulfonamide (sulfadimidine). Optimum exhaustion and fixation values were achieved at 60 g/l sodium sulphate and 20 g/l sodium carbonate for both dyes. The modified dye exhibited higher substantivity, exhaustion and fixation efficiency compared to the commercial dye. Antibacterial activities of the dyed samples at different concentrations of both dyes were studied against gram positive (Staphylococcus aureus) and gram negative (Escherichia coli) bacteria. The cotton dyed with the modified dye shows higher antibacterial efficacy compared to the dyed cotton fabric using the commercial dye, especially on gram negative (E. coli) bacteria. All the reactive dyeings also exhibited high fastness properties. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Eco-Friendly Dyeing of Cotton with Indigo Dye By Electrochemical Method

    Science.gov (United States)

    Prabu, H. Gurumallesh; Sarala, K.; Babu, S. Ananda; Savitha, K. U.

    2011-07-01

    Eco-friendly dyeing of cotton was performed in two step process; (i) enzymatic pre-treatment of grey cotton fabric and (ii) Electrochemical dyeing of the pre-treated cotton fabric with indigo. The enzymatic pre-treatment was done in three methods; (i) amylase treatment only, (ii) amylase and hydrogen peroxide treatment and (iii) single bath method. The dyeing was carried out with the pre-treated cotton fabric. The reduction of indigo dye by electrochemical method was initiated by applying potential. Then the dyeing was carried out different concentrations of dye, glucose and NaOH. Conventional method of dyeing was also carried out and compared with the electrochemical method. Dyeability was measured by computer colour matching (CCM) GretagMacbeth colour eye 2180UV instrument.

  18. High Excitation Transfer Efficiency from Energy Relay Dyes in Dye-Sensitized Solar Cells

    KAUST Repository

    Hardin, Brian E.

    2010-08-11

    The energy relay dye, 4-(Dicyanomethylene)-2-methyl-6-(4- dimethylaminostyryl)-4H-pyran (DCM), was used with a near-infrared sensitizing dye, TT1, to increase the overall power conversion efficiency of a dye-sensitized solar cell (DSC) from 3.5% to 4.5%. The unattached DCM dyes exhibit an average excitation transfer efficiency (EÌ?TE) of 96% inside TT1-covered, mesostructured TiO2 films. Further performance increases were limited by the solubility of DCM in an acetonitrile based electrolyte. This demonstration shows that energy relay dyes can be efficiently implemented in optimized dye-sensitized solar cells, but also highlights the need to design highly soluble energy relay dyes with high molar extinction coefficients. © 2010 American Chemical Society.

  19. High order Bragg grating microfluidic dye laser

    DEFF Research Database (Denmark)

    Balslev, Søren; Kristensen, Anders

    2004-01-01

    We demonstrate a single mode distributed feedback liquid dye laser, based on a short 133 'rd order Bragg grating defined in a single polymer layer between two glass substrates.......We demonstrate a single mode distributed feedback liquid dye laser, based on a short 133 'rd order Bragg grating defined in a single polymer layer between two glass substrates....

  20. Optofluidic third order distributed feedback dye laser

    DEFF Research Database (Denmark)

    Gersborg-Hansen, Morten; Kristensen, Anders

    2006-01-01

    This letter describes the design and operation of a polymer-based third order distributed feedback (DFB) microfluidic dye laser. The device relies on light confinement in a nanostructured polymer film where an array of nanofluidic channels is filled by capillary action with a liquid dye solution...

  1. Predicting Solar-Cell Dyes for Cosensitization

    Energy Technology Data Exchange (ETDEWEB)

    Bayliss, Sam L. [Cavendish; Cole, Jacqueline M. [Cavendish; Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, United States; Institute; Waddell, Paul G. [Cavendish; Australian Nuclear Science and Technology Organization, Lucas Heights, New South Wales 2234, Australia; McKechnie, Scott [Cavendish; Liu, Xiaogang [Cavendish

    2014-06-19

    A major limitation of using organic dyes for dye-sensitized solar cells (DSCs) has been their lack of broad optical absorption. Co-sensitization, in which two complementary dyes are incorporated into a DSC, offers a route to combat this problem. Here we construct and implement a design route for materials discovery of new dyes for co-sensitization, beginning with a chemically compatible series of existing laser dyes which are without an anchor group necessary for DSC use. We determine the crystal structures for this dye series, and use their geometries to establish the DSC molecular design prerequisites aided by density-functional theory and time-dependent density-functional theory calculations. Based on insights gained from these existing dyes, modified sensitizers are computationally designed to include a suitable anchor group. A DSC co-sensitization strategy for these modified sensitizers is predicted, using the central features of highest-occupied, and lowest-unoccupied molecular orbital positioning, optical absorption properties, intramolecular charge-transfer characteristics, and steric effects as selection criteria. Through this molecular engineering of a series of existing non-DSC dyes, we predict new materials for DSC co-sensitization.

  2. EFFECTS OF MORDANTING METHODS OF DYE FROM ...

    African Journals Online (AJOL)

    The effects analyzed are color fastness to; light, washing, wet and dry rubbing and color characteristics on CIELab color coordinates. The aqueous extraction method was used to extract the dye. Some selected mordants were used for dyeing viz; alum, potassium dichromate, ferrous sulphate, iron water and ash water.

  3. Dye Sensitizers for Photodynamic Therapy

    Directory of Open Access Journals (Sweden)

    Harold S. Freeman

    2013-03-01

    Full Text Available Photofrin® was first approved in the 1990s as a sensitizer for use in treating cancer via photodynamic therapy (PDT. Since then a wide variety of dye sensitizers have been developed and a few have been approved for PDT treatment of skin and organ cancers and skin diseases such as acne vulgaris. Porphyrinoid derivatives and precursors have been the most successful in producing requisite singlet oxygen, with Photofrin® still remaining the most efficient sensitizer (quantum yield = 0.89 and having broad food and drug administration (FDA approval for treatment of multiple cancer types. Other porphyrinoid compounds that have received approval from US FDA and regulatory authorities in other countries include benzoporphyrin derivative monoacid ring A (BPD-MA, meta-tetra(hydroxyphenylchlorin (m-THPC, N-aspartyl chlorin e6 (NPe6, and precursors to endogenous protoporphyrin IX (PpIX: 1,5-aminolevulinic acid (ALA, methyl aminolevulinate (MAL, hexaminolevulinate (HAL. Although no non-porphyrin sensitizer has been approved for PDT applications, a small number of anthraquinone, phenothiazine, xanthene, cyanine, and curcuminoid sensitizers are under consideration and some are being evaluated in clinical trials. This review focuses on the nature of PDT, dye sensitizers that have been approved for use in PDT, and compounds that have entered or completed clinical trials as PDT sensitizers.

  4. Two-photon excited photoconversion of cyanine-based dyes

    Science.gov (United States)

    Kwok, Sheldon J. J.; Choi, Myunghwan; Bhayana, Brijesh; Zhang, Xueli; Ran, Chongzhao; Yun, Seok-Hyun

    2016-03-01

    The advent of phototransformable fluorescent proteins has led to significant advances in optical imaging, including the unambiguous tracking of cells over large spatiotemporal scales. However, these proteins typically require activating light in the UV-blue spectrum, which limits their in vivo applicability due to poor light penetration and associated phototoxicity on cells and tissue. We report that cyanine-based, organic dyes can be efficiently photoconverted by nonlinear excitation at the near infrared (NIR) window. Photoconversion likely involves singlet-oxygen mediated photochemical cleavage, yielding blue-shifted fluorescent products. Using SYTO62, a biocompatible and cell-permeable dye, we demonstrate photoconversion in a variety of cell lines, including depth-resolved labeling of cells in 3D culture. Two-photon photoconversion of cyanine-based dyes offer several advantages over existing photoconvertible proteins, including use of minimally toxic NIR light, labeling without need for genetic intervention, rapid kinetics, remote subsurface targeting, and long persistence of photoconverted signal. These findings are expected to be useful for applications involving rapid labeling of cells deep in tissue.

  5. Images.

    Science.gov (United States)

    Barr, Catherine, Ed.

    1997-01-01

    The theme of this month's issue is "Images"--from early paintings and statuary to computer-generated design. Resources on the theme include Web sites, CD-ROMs and software, videos, books, and others. A page of reproducible activities is also provided. Features include photojournalism, inspirational Web sites, art history, pop art, and myths. (AEF)

  6. Molecular engineering of simple phenothiazine-based dyes to modulate dye aggregation, charge recombination, and dye regeneration in highly efficient dye-sensitized solar cells.

    Science.gov (United States)

    Hua, Yong; Chang, Shuai; He, Jian; Zhang, Caishun; Zhao, Jianzhang; Chen, Tao; Wong, Wai-Yeung; Wong, Wai-Kwok; Zhu, Xunjin

    2014-05-19

    A series of simple phenothiazine-based dyes, namely, TP, EP, TTP, ETP, and EEP have been developed, in which the thiophene (T), ethylenedioxythiophene (E), their dimers, and mixtures are present to modulate dye aggregation, charge recombination, and dye regeneration for highly efficient dye-sensitized solar cell (DSSC) applications. Devices sensitized by the dyes TP and TTP display high power conversion efficiencies (PCEs) of 8.07 (Jsc = 15.2 mA cm(-2), Voc =0.783 V, fill factor (FF) = 0.679) and 7.87 % (Jsc = 16.1 mA cm(-2), Voc = 0.717 V, FF = 0.681), respectively; these were measured under simulated AM 1.5 sunlight in conjunction with the I(-)/I3(-) redox couple. By replacing the T group with the E unit, EP-based DSSCs had a slightly lower PCE of 7.98 % with a higher short-circuit photocurrent (Jsc) of 16.7 mA cm(-2). The dye ETP, with a mixture of E and T, had an even lower PCE of 5.62 %. Specifically, the cell based on the dye EEP, with a dimer of E, had inferior Jsc and Voc values and corresponded to the lowest PCE of 2.24 %. The results indicate that the photovoltaic performance can be finely modulated through structural engineering of the dyes. The selection of T analogues as donors can not only modulate light absorption and energy levels, but also have an impact on dye aggregation and interfacial charge recombination of electrons at the interface of titania, electrolytes, and/or oxidized dye molecules; this was demonstrated through DFT calculations, electrochemical impedance analysis, and transient photovoltage studies. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. A Review on Current Status of Stability and Knowledge on Liquid Electrolyte-Based Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Frédéric Sauvage

    2014-01-01

    Full Text Available The purpose of this review is to gather the current background in materials development and provide the reader with an accurate image of today’s knowledge regarding the stability of dye-sensitized solar cells. This contribution highlights the literature from the 1970s to the present day on nanostructured TiO2, dye, Pt counter electrode, and liquid electrolyte for which this review is focused on.

  8. Reduction of colorants in nylon flock dyeing effluent

    Science.gov (United States)

    Fan, Qinguo; Hoskote, Sunil; Hou, Yuejun

    2001-02-01

    The batch dyeing of fiber materials such as staple fibers and flock is usually carried out by exhaustion methods. However, the dyeing of flock fibers, either nylon, PET or acetate, with acid or disperse dyes is not 100 percent efficient in terms of dye utilization. Optimally, only about 80 to 85% of the dyes used for dark shade in a dye bath can be exhausted onto the target fibers. Therefore, the remaining dyes in the spent dye bath are generally not reused and are usually discharged with minimum treatment, together with the dyeing chemicals into the sewage wastewater system causing environmental pollution. We are presenting technical solutions to reduce the colorants and chemical auxiliaries in the fiber dyeing effluents by: (1) optimizing the acid dyeing conditions such as salt addition and pH control; (2) reuse of the spent dye bath that remain after the original dyeing process. In the lab scale trials, we have successfully raised the acid dye exhaustion to over 90% by optimizing the dyeing conditions. The reuse of the spent acid dye bath also showed promising results with dye exhaustion ranging from 91 to 93% after 4 times reuse.

  9. Performance improvement of dye-sensitized solar cells (DSSC) by using dyes mixture from chlorophyll and anthocyanin

    Science.gov (United States)

    Pratiwi, D. D.; Nurosyid, F.; Kusumandari; Supriyanto, A.; Suryana, R.

    2017-11-01

    This article showed the effect of single and mixture natural dyes on the DSSC performance. The single dyes extracted from moss chlorophyll and mangosteen peels anthocyanin. The dyes mixture was prepared by mixing from both chlorophyll and anthocyanin. The absorbance of dyes solution and the adsorption of the dye onto the working electrode were analyzed using UV-Vis spectroscopy. The photocurrent-photovoltage of DSSCs were measured using I-V meter. The dyes mixture has an increased absorption at visible spectrum range as compared to single dye. The adsorption of the dyes mixture onto the TiO2 electrode has higher absorbance than single dye. The DSSC with single dye from moss chlorophyll and mangosteen peels anthocyanin resulted the conversion efficiency of 0.049% and 0.042% respectively. The dyes mixture of chlorophyll and anthocyanin improved the conversion efficiency of 0.154%.

  10. Adsorption of Dyes Using Different Types of Sand: A Review

    African Journals Online (AJOL)

    NICO

    KEYWORDS. Adsorption, dyes, low-cost adsorbents, sand. 1. Introduction. Several dyes and their break-down products are toxic for living organisms because dyes are not easily degradable and are gener- ally not removed from wastewater by conventional wastewater treatment systems; this makes it difficult to remove dyes ...

  11. Traditional Cloth Dyeing Enterprise at Ntonso: Challenges and ...

    African Journals Online (AJOL)

    There is a growing awareness to the threats posed by synthetic dyes. Natural plant-based dyes have proved to be important alternatives to synthetic dyes in the textile industry. The study investigated the traditional cottage textile dyeing enterprise at Ntonso, in the Ashanti Region of Ghana, to identify challenges facing the ...

  12. Removal of hazardous dye Ponceau-S by using Chitin:

    African Journals Online (AJOL)

    Sr030111Bin Comp

    Dye pollutants from textile dye industries are an important source of environment contamination. The dyes currently used in textile industry is about 10,000 (Poon et al., 1999) .It is estimated that 1-155 of the dyes are .... 100 ml red solution of Ponceau-S .The mixture was stirred on magnetic stirrer for different interval of time.

  13. Bleaching and diffusion dynamics in optofluidic dye lasers

    DEFF Research Database (Denmark)

    Gersborg-Hansen, Morten; Balslev, Søren; Mortensen, Asger

    2007-01-01

    The authors have investigated the bleaching dynamics that occur in optofluidic dye lasers where the liquid laser dye in a microfluidic channel is locally bleached due to optical pumping. They find that for microfluidic devices, the dye bleaching may be compensated through diffusion of dye molecules...... pumping devices. ©2007 American Institute of Physics....

  14. Comparative properties of pure and sulphonated dyes extracted ...

    African Journals Online (AJOL)

    Both the extracted and sulphonated dyes were applied on chrome-tanned leather using 2% and liquor-togood ratio of 50:1 dyeing conditions and the dyeing properties (exhaustion, fixation, glazing, levelness, migration and penetration) assessed. The light, wash and rub fastness properties of the dyeings were investigated.

  15. Standardization in biological staining. The influence of dye manufacturing

    DEFF Research Database (Denmark)

    Lyon, H

    2000-01-01

    for biological staining, standardization of all procedures and reagents is mandatory. In this paper, I focus particularly on dyes and consider the possibilities for obtaining standardized dyes. In general practice, most biological staining takes place with available commercial dyes. These dyes may or may...

  16. Synthesis and characterization of reactive dye-cassava mesocarp ...

    African Journals Online (AJOL)

    Results obtained show that the dyes have excellent dyeing properties attributable to chemical bond formation between the dye molecules and the hydroxyl groups of the substrate (cassava mesocarp). The satisfactory fastness properties and good dye fixation on the substrate are of importance in the preparation of stable ...

  17. Contact allergy to common ingredients in hair dyes

    DEFF Research Database (Denmark)

    Søsted, Heidi; Rustemeyer, Thomas; Gonçalo, Margarida

    2013-01-01

    p-Phenylenediamine (PPD) is the primary patch test screening agent for hair dye contact allergy, and approximately 100 different hair dye chemicals are allowed.......p-Phenylenediamine (PPD) is the primary patch test screening agent for hair dye contact allergy, and approximately 100 different hair dye chemicals are allowed....

  18. Supramolecular hair dyes: a new application of cocrystallization

    DEFF Research Database (Denmark)

    Delori, Amit; Urquhart, Andrew; Oswald, Iain D. H.

    2016-01-01

    The manuscript presents the first report of hair dyes of various colors formed by cocrystallization. Unlike the most popular oxidative hair dye (OHD) products, these dyes are NH3 free and do not require H2O2 as a color developer. The importance of these new hair dyes products is further enhanced...

  19. Hypersensitivity to contrast media and dyes.

    Science.gov (United States)

    Brockow, Knut; Sánchez-Borges, Mario

    2014-08-01

    This article updates current knowledge on hypersensitivity reactions to diagnostic contrast media and dyes. After application of a single iodinated radiocontrast medium (RCM), gadolinium-based contrast medium, fluorescein, or a blue dye, a hypersensitivity reaction is not a common finding; however, because of the high and still increasing frequency of those procedures, patients who have experienced severe reactions are nevertheless frequently encountered in allergy departments. Evidence on allergologic testing and management is best for iodinated RCM, limited for blue dyes, and insufficient for fluorescein. Skin tests can be helpful in the diagnosis of patients with hypersensitivity reactions to these compounds. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Dye ingredients and energy conversion efficiency at natural dye sensitized solar cells

    Science.gov (United States)

    Özbay Karakuş, Mücella; Koca, İrfan; Er, Orhan; Çetin, Hidayet

    2017-04-01

    In this work, natural dyes extracted from the same genus but different species flowers were used as sensitizer in Dye Sensitized Solar Cell (DSSC). To clearly show dye ingredients effect on electrical characteristics, the same genus flowers were selected. The dye ingredients were analyzed by Gas Chromatography Mass Spectrometer (GC-MS). The dyes were modified by a procedure that includes refluxing in acetone. All results indicate a relationship between gallic acid quantity in dyes and solar cell efficiency. To gain further insight, the solar cell parameters were obtained by using the single-diode and double-diode models and they were compared to each other. It was observed that the applied process causes a decrease in series resistance. How the modification process and gallic acid affect energy conversion efficiency were argued in detail in the frame of results that were obtained from solar cell models.

  1. Conducting polymers based counter electrodes for dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Veerender, P., E-mail: veeru1009@gmail.com, E-mail: veeru1009@gmail.com; Saxena, Vibha, E-mail: veeru1009@gmail.com, E-mail: veeru1009@gmail.com; Gusain, Abhay, E-mail: veeru1009@gmail.com, E-mail: veeru1009@gmail.com; Jha, P., E-mail: veeru1009@gmail.com, E-mail: veeru1009@gmail.com; Koiry, S. P., E-mail: veeru1009@gmail.com, E-mail: veeru1009@gmail.com; Chauhan, A. K., E-mail: veeru1009@gmail.com, E-mail: veeru1009@gmail.com; Aswal, D. K., E-mail: veeru1009@gmail.com, E-mail: veeru1009@gmail.com; Gupta, S. K., E-mail: veeru1009@gmail.com, E-mail: veeru1009@gmail.com [Technical Physics Division, Bhabha Atomic Research Centre, Mumbai - 400085 (India)

    2014-04-24

    Conducting polymer films were synthesized and employed as an alternative to expensive platinum counter electrodes for dye-sensitized solar cells. poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) thin films were spin-coated and polypyrrole films were electrochemically deposited via cyclic voltammetry method on ITO substrates. The morphology of the films were imaged by SEM and AFM. These films show good catalytic activity towards triiodide reduction as compared to Pt/FTO electrodes. Finally the photovoltaic performance of DSSC fabricated using N3 dye were compared with PT/FTO, PEDOT/ITO, and e-PPy counter electrodes.

  2. USE OF A NATURAL DYE FROM SERRATIA MARCESCENS SUBSPECIES MARCESCENS IN DYEING OF TEXTILE FABRICS

    OpenAIRE

    Ravindra Adivarekar; Jyoti Vaidyanathan; Madhura Nerurkar

    2013-01-01

    A strain of Serratia marcescens subspecies marcescens capable of producing a novel rose red pigment with a mass of 112 Da has been isolated from Mahim Mangroove soil. Studies regarding the growth conditions of bacteria, partial characterization of the produced pigment and use of this rose red pigment to dye natural fabrics has been studied and described. Dyeing of wool, cotton and silk fabrics with this rose red microbial pigment as natural dye indicated that the colour strength values and t...

  3. Imaging electric field dynamics with graphene optoelectronics.

    Science.gov (United States)

    Horng, Jason; Balch, Halleh B; McGuire, Allister F; Tsai, Hsin-Zon; Forrester, Patrick R; Crommie, Michael F; Cui, Bianxiao; Wang, Feng

    2016-12-16

    The use of electric fields for signalling and control in liquids is widespread, spanning bioelectric activity in cells to electrical manipulation of microstructures in lab-on-a-chip devices. However, an appropriate tool to resolve the spatio-temporal distribution of electric fields over a large dynamic range has yet to be developed. Here we present a label-free method to image local electric fields in real time and under ambient conditions. Our technique combines the unique gate-variable optical transitions of graphene with a critically coupled planar waveguide platform that enables highly sensitive detection of local electric fields with a voltage sensitivity of a few microvolts, a spatial resolution of tens of micrometres and a frequency response over tens of kilohertz. Our imaging platform enables parallel detection of electric fields over a large field of view and can be tailored to broad applications spanning lab-on-a-chip device engineering to analysis of bioelectric phenomena.

  4. Chromoendoscopy with indigo carmine dye added to acetic acid in the diagnosis of gastric neoplasia: a prospective comparative study.

    Science.gov (United States)

    Sakai, Yuzo; Eto, Reiko; Kasanuki, Junji; Kondo, Fukuo; Kato, Kazuki; Arai, Makoto; Suzuki, Takuto; Kobayashi, Michiko; Matsumura, Tomoaki; Bekku, Dan; Ito, Kenichi; Nakamoto, Shingo; Tanaka, Takeshi; Yokosuka, Osamu

    2008-10-01

    Conventional endoscopy and chromoendoscopy with indigo carmine dye are usually performed for recognizing adequate tumor-negative lateral margins for successful endoscopic resection of gastric neoplasia. However, chromoendoscopy with indigo carmine dye added to acetic acid has not been used for this purpose. Our purpose was to compare the diagnostic performance of chromoendoscopy with indigo carmine dye added to acetic acid with that of conventional endoscopy and chromoendoscopy with indigo carmine dye or acetic acid alone. Prospective study. Social Insurance Funabashi Central Hospital. Forty-seven consecutive patients (53 lesions) with early gastric cancer and gastric adenomas who underwent endoscopic submucosal dissection (ESD) from April 2006 to July 2007 were studied. All the lesions were examined by the endoscopic modalities before ESD, and the resected specimens were analyzed histopathologically. Two endoscopists independently evaluated the diagnostic performance of each image in terms of recognition of tumor borders with reference to macroscopic and histopathologic findings of resected specimens. We also conducted a substudy to assess interobserver variability. There was good interobserver agreement between the 2 endoscopists in this study (kappa index = 0.764). The diagnostic performance of chromoendoscopy with indigo carmine dye added to acetic acid was significantly greater than that of any of the other modalities (vs each: P indigo carmine dye added to acetic acid was better compared with conventional endoscopy and chromoendoscopy by using only indigo carmine dye or acetic acid. The applicability of this method for gastric neoplasia merits further investigation.

  5. Effect of Solvent, Dye-Loading Time, and Dye Choice on the Performance of Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Fahd M. Rajab

    2016-01-01

    Full Text Available Anatase titania films with a thickness of up to 20 μm and deposited over a fluorine-doped tin-oxide substrate are impregnated with ruthenium dyes N-719 and N-749 using Dip and supercritical-fluid methods for the purpose of fabricating dye-sensitized solar cell devices. The dyes are dissolved in different solvent mixtures, including supercritical carbon dioxide, as well as combinations of more traditional solvents including mixtures of acetonitrile, and t-butanol. Analytical studies included thin-film analyzing and scanning electron microscopy to measure titania film thickness and porosity, UV-Vis spectroscopy to quantify dye concentration, and current-voltage device characterizations to assess energy conversion efficiency, as well as open-circuit voltage decay measurements and quantum efficiency to examine electron collection efficiency. A significant result is that using the dye N-749 in a solvent that includes supercritical carbon dioxide leads to energy conversion efficiencies that are higher for devices with a thick 20 μm semiconductor film than for the case of devices with thinner films, including the 10 μm film thickness that is traditionally considered an upper threshold. The supercritical-fluid method for the N-719 dye also enabled shorter impregnation duration than more conventional classical Dip Methods.

  6. Data mining with molecular design rules identifies new class of dyes for dye-sensitised solar cells

    NARCIS (Netherlands)

    Cole, Jacqueline M.; Low, Kian Sing; Ozoe, Hiroaki; Stathi, Panagiota; Kitamura, Chitoshi; Kurata, Hiroyuki; Rudolf, Petra; Kawase, Takeshi

    2014-01-01

    A major deficit in suitable dyes is stifling progress in the dye-sensitised solar cell (DSC) industry. Materials discovery strategies have afforded numerous new dyes; yet, corresponding solution-based DSC device performance has little improved upon 11% efficiency, achieved using the N719 dye over

  7. Whispering-gallery-mode dye lasers in blue, green, and orange regions using dye-doped, solid, small spheres

    OpenAIRE

    Taniguchi, Hiroshi; Fujiwara, Tamiya; Yamada, Hiroshi; Tanosaki, Shinji; Baba, Mamoru

    1993-01-01

    A whispering-gallery-mode (WGM) dye laser in blue, green, and orange regions is reported using dye-doped, solid, small spheres. A WGM dye laser is pumped by a transversely excited atmospheric UV N2 laser. Some features of the WGM dye laser are demonstrated.

  8. Bioremediation of dyes by fungi isolated from contaminated dye effluent sites for bio-usability

    Science.gov (United States)

    Rani, Babita; Kumar, Vivek; Singh, Jagvijay; Bisht, Sandeep; Teotia, Priyanku; Sharma, Shivesh; Kela, Ritu

    2014-01-01

    Biodegradation and detoxification of dyes, Malachite green, Nigrosin and Basic fuchsin have been carried out using two fungal isolates Aspergillus niger, and Phanerochaete chrysosporium, isolated from dye effluent soil. Three methods were selected for biodegradation, viz. agar overlay and liquid media methods; stationary and shaking conditions at 25 °C. Aspergillus niger recorded maximum decolorization of the dye Basic fuchsin (81.85%) followed by Nigrosin (77.47%), Malachite green (72.77%) and dye mixture (33.08%) under shaking condition. Whereas, P. chrysosporium recorded decolorization to the maximum with the Nigrosin (90.15%) followed by Basic fuchsin (89.8%), Malachite green (83.25%) and mixture (78.4%). The selected fungal strains performed better under shaking conditions compared to stationary method; moreover the inoculation of fungus also brought the pH of the dye solutions to neutral from acidic. Seed germination bioassay study exhibited that when inoculated dye solutions were used, seed showed germination while uninoculated dyes inhibited germination even after four days of observation. Similarly, microbial growth was also inhibited by uninoculated dyes. The excellent performance of A. niger and P. chrysporium in the biodegradation of textile dyes of different chemical structures suggests and reinforces the potential of these fungi for environmental decontamination. PMID:25477943

  9. Transforming Benzophenoxazine Laser Dyes into Chromophores for Dye-Sensitized Solar Cells: A Molecular Engineering Approach

    Energy Technology Data Exchange (ETDEWEB)

    Schröder, Florian A. Y. N. [Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue Cambridge CB3 0HE UK; Cole, Jacqueline M. [Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue Cambridge CB3 0HE UK; Argonne National Laboratory, 9700 S. Cass Avenue Argonne IL 60439 USA; International Institute for Complex Adaptive Matter, University of California Davis, Davis CA 95616 USA; Waddell, Paul G. [Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue Cambridge CB3 0HE UK; Australian Nuclear Science and Technology Organization, Lucas Heights, New South Wales 2234 Australia; McKechnie, Scott [Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue Cambridge CB3 0HE UK

    2015-02-03

    The re-functionalization of a series of four well-known industrial laser dyes, based on benzophenoxazine, is explored with the prospect of molecularly engineering new chromophores for dye-sensitized solar cell (DSC) applications. Such engineering is important since a lack of suitable dyes is stifling the progress of DSC technology. The conceptual idea involves making laser dyes DSC-active by chemical modification, while maintaining their key property attributes that are attractive to DSC applications. This molecular engineering follows a step-wise approach. Firstly, molecular structures and optical absorption properties are determined for the parent laser dyes: Cresyl Violet (1); Oxazine 170 (2); Nile Blue A (3), Oxazine 750 (4). These reveal structure-property relationships which define the prerequisites for computational molecular design of DSC dyes; the nature of their molecular architecture (D-π-A) and intramolecular charge transfer. Secondly, new DSC dyes are computationally designed by the in silico addition of a carboxylic acid anchor at various chemical substitution points in the parent laser dyes. A comparison of the resulting frontier molecular orbital energy levels with the conduction band edge of a TiO2 DSC photoanode and the redox potential of two electrolyte options I-/I3- and Co(II/III)tris(bipyridyl) suggests promise for these computationally designed dyes as co-sensitizers for DSC applications.

  10. DFT Studies on the electronic structures of indoline dyes for dye-sensitized solar cells

    Directory of Open Access Journals (Sweden)

    JIE XU

    2010-02-01

    Full Text Available A series of indoline dyes with promising efficiency for dye-sensitized solar cells (DSSCs were studied using the density functional theory at the B3LYP/6-31g (d level. The ground-state geometries, electronic structures and absorption spectra of these dyes are reported. The calculated results indicate that the energy levels of the HOMOs and LUMOs of these dyes are advantageous for electron injection. Their intense and broad absorption bands as well as favorable excited-state energy levels are key factor for their outstanding efficiencies in DSSCs.

  11. Chromosome characterization using single fluorescent dye

    Energy Technology Data Exchange (ETDEWEB)

    Crissman, Harry A. (Los Alamos, NM); Hirons, Gregory T. (Irvine, CA)

    1995-01-01

    Chromosomes are characterized by fluorescent emissions from a single fluorescent dye that is excited over two different wavelengths. A mixture containing chromosomes is stained with a single dye selected from the group consisting of TOTO and YOYO and the stained chromosomes are placed in a flow cytometer. The fluorescent dye is excited sequentially by a first light having a wavelength in the ultraviolet range to excite the TOTO or YOYO to fluoresce at a first intensity and by a second light having a wavelength effective to excite the TOTO or YOYO dye to fluoresce at a second intensity. Specific chromosomes may be identified and sorted by intensity relationships between the first and second fluorescence emissions.

  12. Visible Light Dye-Sensitized Photosensititve Systems

    National Research Council Canada - National Science Library

    Fang Gao; Yong-yuan Yang

    2000-01-01

      The visible light dyes were employed to sensitized o-Cl-Hexaarylbiimidazole (o-Cl-HABI). The obtained results suggested that o-Cl-HABI displayed a efficient sensitized photocleavage when exposed to Xenon lamp...

  13. and dyes metabolized to benzidine were

    African Journals Online (AJOL)

    LAB

    2012-07-17

    Jul 17, 2012 ... Immobilized bitter gourd peroxidase was used for the successful and effective removal of water ..... the compounds that speed up the reaction rate by .... dyes mediated by partially purified turnip (Brassica rapa) peroxidase.

  14. Modeling the efficiency of Förster resonant energy transfer from energy relay dyes in dye-sensitized solar cells

    KAUST Repository

    Hoke, Eric T.

    2010-02-11

    Förster resonant energy transfer can improve the spectral breadth, absorption and energy conversion efficiency of dye sensitized solar cells. In this design, unattached relay dyes absorb the high energy photons and transfer the excitation to sensitizing dye molecules by Förster resonant energy transfer. We use an analytic theory to calculate the excitation transfer efficiency from the relay dye to the sensitizing dye accounting for dynamic quenching and relay dye diffusion. We present calculations for pores of cylindrical and spherical geometry and examine the effects of the Förster radius, the pore size, sensitizing dye surface concentration, collisional quenching rate, and relay dye lifetime. We find that the excitation transfer efficiency can easily exceed 90% for appropriately chosen dyes and propose two different strategies for selecting dyes to achieve record power conversion efficiencies. © 2010 Optical Society of America.

  15. Pre dye treated titanium dioxide nanoparticles synthesized by modified sol-gel method for efficient dye-sensitized solar cells

    Science.gov (United States)

    Ananth, S.; Vivek, P.; Arumanayagam, T.; Murugakoothan, P.

    2015-06-01

    Pure and pre dye treated titanium dioxide nanoparticles were prepared by sol-gel and modified sol-gel methods, respectively. The pre dye treatment has improved the properties of TiO2, such as uniform dye adsorption, reduced agglomeration, improved morphology and less dye aggregation. The brazilein pigment-rich Caesalpinia sappan heartwood extract was used as natural dye sensitizer for pure and pre dye treated TiO2 nanoparticles. Low cost and environment friendly dye-sensitized solar cells (DSSC) fabricated using pure and pre dye treated TiO2 nanoparticles sensitized by natural dye showed solar light to electron conversion efficiencies of 1.09 and 1.65 %, respectively. The pre dye treated TiO2-based DSSC showed 51 % improvement in efficiency when compared to that of conventionally prepared DSSC.

  16. Improved Charge-Transfer Fluorescent Dyes

    Science.gov (United States)

    Meador, Michael

    2005-01-01

    Improved charge-transfer fluorescent dyes have been developed for use as molecular probes. These dyes are based on benzofuran nuclei with attached phenyl groups substituted with, variously, electron donors, electron acceptors, or combinations of donors and acceptors. Optionally, these dyes could be incorporated as parts of polymer backbones or as pendant groups or attached to certain surfaces via self-assembly-based methods. These dyes exhibit high fluorescence quantum yields -- ranging from 0.2 to 0.98, depending upon solvents and chemical structures. The wavelengths, quantum yields, intensities, and lifetimes of the fluorescence emitted by these dyes vary with (and, hence, can be used as indicators of) the polarities of solvents in which they are dissolved: In solvents of increasing polarity, fluorescence spectra shift to longer wavelengths, fluorescence quantum yields decrease, and fluorescence lifetimes increase. The wavelengths, quantum yields, intensities, and lifetimes are also expected to be sensitive to viscosities and/or glass-transition temperatures. Some chemical species -- especially amines, amino acids, and metal ions -- quench the fluorescence of these dyes, with consequent reductions in intensities, quantum yields, and lifetimes. As a result, the dyes can be used to detect these species. Another useful characteristic of these dyes is a capability for both two-photon and one-photon absorption. Typically, these dyes absorb single photons in the ultraviolet region of the spectrum (wavelengths fluorescence spectra identical to those obtained in response to excitation by single photons at half the corresponding wavelengths (300 to 400 nm). While many prior fluorescent dyes exhibit high quantum yields, solvent-polarity- dependent fluorescence behavior, susceptibility to quenching by certain chemical species, and/or two-photon fluorescence, none of them has the combination of all of these attributes. Because the present dyes do have all of these attributes

  17. Photocatalytic degradation of three azo dyes using immobilized TiO{sub 2} nanoparticles on glass plates activated by UV light irradiation: Influence of dye molecular structure

    Energy Technology Data Exchange (ETDEWEB)

    Khataee, A.R., E-mail: a_khataee@tabrizu.ac.ir [Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of); Laboratoire des Sciences du Genie Chimique, CNRS, Nancy Universite, ENSIC, 1, rue Grandville, BP 20451, F-54001 Nancy Cedex (France); Pons, M.N., E-mail: Marie-Noelle.Pons@ensic.inpl-nancy.fr [Laboratoire des Sciences du Genie Chimique, CNRS, Nancy Universite, ENSIC, 1, rue Grandville, BP 20451, F-54001 Nancy Cedex (France); Zahraa, O., E-mail: Orfan.Zahraa@ensic.inpl-nancy.fr [Departement de Chimie-Physique des Reactions, INPL, Nancy Universite, ENSIC, 1, rue Grandville, BP 451, F-54001 Nancy Cedex (France)

    2009-08-30

    In order to discuss the effect of chemical structure on photocatalysis efficiency, the photocatalytic degradation of three commercial textile dyes (C.I. Acid Orange 10 (AO10), C.I. Acid Orange 12 (AO12) and C.I. Acid Orange 8 (AO8)) with different structure and different substitute groups has been investigated using supported TiO{sub 2} photocatalyst under UV light irradiation. All the experiments were performed in a circulation photochemical reactor equipped with a 15-W UV lamp emitted around 365 nm. The investigated photocatalyst was industrial Millennium PC-500 (crystallites mean size 5-10 nm) immobilized on glass plates by a heat attachment method. SEM images of the immobilized TiO{sub 2} nanoparticles showed the good coating on the plates, after repeating the deposition procedure three times. Our results indicated that the photocatalytic decolorization kinetics of the dyes were in the order of AO10 > AO12 > AO8. Photocatalytic mineralization of the dyes was monitored by total organic carbon (TOC) decrease, changes in UV-vis spectra and ammonium ion formation. The dye solutions could be completely decolorized and effectively mineralized, with an average overall TOC removal larger than 94% for a photocatalytic reaction time of 6 h. The nitrogen-to-nitrogen double bond of the azo dyes was transformed predominantly into NH{sub 4}{sup +} ion. The kinetic of photocatalytic decolorization of the dyes was found to follow a first-order rate law. The photocatalysis efficiency was evaluated by figure-of-merit electrical energy per order (E{sub EO}).

  18. Development of New Laser Protective Dyes

    Science.gov (United States)

    1993-07-31

    III; SBIR; Phase II; Laser; Laser Hazards; Laser Dye Synthesis; Ocular Protection; Ocular 16. PRICE CODE Hazard 17. SECURITY CLASSIFICATION 18...DyelPlastic Combinations Investigated during this Program DYE PLASTIC* Xmax (nrm) SS-1044 PETG 834 PC-- SS-1045 PC 777 SS-1049 PETG 1070 PC 3S-1101 PMMA 850/990...1151 PC 860 SS-1155 PETG 1060 PC SS-1159 PC 980 SS-1161 PC 755 PETG-Polyethylene tcrphtlmlate glycolate, PC-PolycazboWate, PMMA -polymethyl methacrybe

  19. Synthesis of azoimidazolium dyes with nitrous oxide.

    Science.gov (United States)

    Tskhovrebov, Alexander G; Naested, Lara C E; Solari, Euro; Scopelliti, Rosario; Severin, Kay

    2015-01-19

    A new method for the synthesis of industrially important azoimidazolium dyes is presented. The procedure is based on a reagent which is rarely used in the context of synthetic organic chemistry: nitrous oxide ("laughing gas"). N2O is first coupled to N-heterocyclic carbenes. Subsequent reaction with aromatic compounds through an AlCl3-induced C-H activation process provides azoimidazolium dyes in good yields. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Liquid crystal tunable photonic crystal dye laser

    DEFF Research Database (Denmark)

    Buss, Thomas; Christiansen, Mads Brøkner; Smith, Cameron

    2010-01-01

    We present a dye-doped liquid crystal laser using a photonic crystal cavity. An applied electric field to the liquid crystal provides wavelength tunability. The photonic crystal enhances resonant interaction with the gain medium.......We present a dye-doped liquid crystal laser using a photonic crystal cavity. An applied electric field to the liquid crystal provides wavelength tunability. The photonic crystal enhances resonant interaction with the gain medium....

  1. Phytoremediation in education: textile dye teaching experiments.

    Science.gov (United States)

    Ibbini, Jwan H; Davis, Lawrence C; Erickson, Larry E

    2009-07-01

    Phytoremediation, the use of plants to clean up contaminated soil and water, has a wide range of applications and advantages, and can be extended to scientific education. Phytoremediation of textile dyes can be used as a scientific experiment or demonstration in teaching laboratories of middle school, high school and college students. In the experiments that we developed, students were involved in a hands-on activity where they were able to learn about phytoremediation concepts. Experiments were set up with 20-40 mg L(-1) dye solutions of different colors. Students can be involved in the set up process and may be involved in the experimental design. In its simplest forms, they use two-week-old sunflower seedlings and place them into a test tube of known volume of dye solution. Color change and/or dye disappearance can be monitored by visual comparison or with a spectrophotometer. Intensity and extent of the lab work depends on student's educational level, and time constraints. Among the many dyes tested, Evan's Blue proved to be the most readily decolorized azo dye. Results could be observed within 1-2 hours. From our experience, dye phytoremediation experiments are suitable and easy to understand by both college and middle school students. These experiments help visual learners, as students compare the color of the dye solution before and after the plant application. In general, simple phytoremediation experiments of this kind can be introduced in many classes including biology, biochemistry and ecological engineering. This paper presents success stories of teaching phytoremediation to middle school and college students.

  2. Use of dyes to increase phase contrast for biological holographic microscopy.

    Science.gov (United States)

    Nadeau, Jay L; Cho, Yong Bin; Lindensmith, Christian A

    2015-09-01

    Holographic microscopy is an emerging biological technique that provides amplitude and quantitative phase imaging, though the contrast provided by many cell types and organelles is low, and until now no dyes were known that increased contrast. Here we show that the metallocorrole Ga(tpfc)(SO3)2, which has a strong Soret band absorption, increases contrast in both amplitude and phase and facilitates tracking of Escherichia coli with minimal toxicity. The change in phase contrast may be calculated from the dye-absorbance spectrum using the Kramers-Kronig relations, and represents a general principle that may be applied to any dye or cell type. This enables the use of holographic microscopy for all applications in which specific labeling is desired.

  3. Thermoresponsive cellulose ether and its flocculation behavior for organic dye removal.

    Science.gov (United States)

    Tian, Ye; Ju, Benzhi; Zhang, Shufen; Hou, Linan

    2016-01-20

    A thermoresponsive polymer, 2-hydroxy-3-butoxypropyl hydroxyethyl cellulose (HBPEC), was prepared by grafting butyl glycidyl ether (BGE) onto hydroxyethyl cellulose (HEC). The lower critical solution temperature (LCST) and critical flocculation temperature (CFT) of HBPEC were varied by changing the molar substitution (MS) and salt concentrations. Transmission electron microscopy (TEM) images and fluorescence spectroscopy showed that HBPEC can assemble into micelles. Additionally, using Nile Red as a model dye, the performance of HBPEC for the removing Nile Red from aqueous solutions via cloud point extraction procedures was investigated in detail. The encapsulation behavior of dye in the aqueous solution of HBPEC was studied by fluorescence spectroscopy and fluorescence microscope. The experimental results indicated that 99.4% of dye was removed from the aqueous solutions, and the HBPEC was recycled and reused easily, Furthermore, the recycle efficiency (RE) and maximum loading capacity portrayed little loss with the number of cycles. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Degradation of textile dyes by cyanobacteria

    Directory of Open Access Journals (Sweden)

    Priscila Maria Dellamatrice

    Full Text Available Abstract Dyes are recalcitrant compounds that resist conventional biological treatments. The degradation of three textile dyes (Indigo, RBBR and Sulphur Black, and the dye-containing liquid effluent and solid waste from the Municipal Treatment Station, Americana, São Paulo, Brazil, by the cyanobacteria Anabaena flos-aquae UTCC64, Phormidium autumnale UTEX1580 and Synechococcus sp. PCC7942 was evaluated. The dye degradation efficiency of the cyanobacteria was compared with anaerobic and anaerobic-aerobic systems in terms of discolouration and toxicity evaluations. The discoloration was evaluated by absorption spectroscopy. Toxicity was measured using the organisms Hydra attenuata, the alga Selenastrum capricornutum and lettuce seeds. The three cyanobacteria showed the potential to remediate textile effluent by removing the colour and reducing the toxicity. However, the growth of cyanobacteria on sludge was slow and discoloration was not efficient. The cyanobacteria P. autumnale UTEX1580 was the only strain that completely degraded the indigo dye. An evaluation of the mutagenicity potential was performed by use of the micronucleus assay using Allium sp. No mutagenicity was observed after the treatment. Two metabolites were produced during the degradation, anthranilic acid and isatin, but toxicity did not increase after the treatment. The cyanobacteria showed the ability to degrade the dyes present in a textile effluent; therefore, they can be used in a tertiary treatment of effluents with recalcitrant compounds.

  5. Degradation of textile dyes by cyanobacteria.

    Science.gov (United States)

    Dellamatrice, Priscila Maria; Silva-Stenico, Maria Estela; Moraes, Luiz Alberto Beraldo de; Fiore, Marli Fátima; Monteiro, Regina Teresa Rosim

    Dyes are recalcitrant compounds that resist conventional biological treatments. The degradation of three textile dyes (Indigo, RBBR and Sulphur Black), and the dye-containing liquid effluent and solid waste from the Municipal Treatment Station, Americana, São Paulo, Brazil, by the cyanobacteria Anabaena flos-aquae UTCC64, Phormidium autumnale UTEX1580 and Synechococcus sp. PCC7942 was evaluated. The dye degradation efficiency of the cyanobacteria was compared with anaerobic and anaerobic-aerobic systems in terms of discolouration and toxicity evaluations. The discoloration was evaluated by absorption spectroscopy. Toxicity was measured using the organisms Hydra attenuata, the alga Selenastrum capricornutum and lettuce seeds. The three cyanobacteria showed the potential to remediate textile effluent by removing the colour and reducing the toxicity. However, the growth of cyanobacteria on sludge was slow and discoloration was not efficient. The cyanobacteria P. autumnale UTEX1580 was the only strain that completely degraded the indigo dye. An evaluation of the mutagenicity potential was performed by use of the micronucleus assay using Allium sp. No mutagenicity was observed after the treatment. Two metabolites were produced during the degradation, anthranilic acid and isatin, but toxicity did not increase after the treatment. The cyanobacteria showed the ability to degrade the dyes present in a textile effluent; therefore, they can be used in a tertiary treatment of effluents with recalcitrant compounds. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  6. Chitosan derivatives as biosorbents for basic dyes.

    Science.gov (United States)

    Lazaridis, Nikolaos K; Kyzas, George Z; Vassiliou, Alexandros A; Bikiaris, Dimitrios N

    2007-07-03

    The scope of this study was to prepare and evaluate chitosan derivatives as biosorbents for basic dyes. This was achieved by grafting poly (acrylic acid) and poly (acrylamide) through persulfate induced free radical initiated polymerization processes and covalent cross-linking of the prepared materials. Remacryl Red TGL was used as the cationic dye. Equilibrium sorption experiments were carried out at different pH and initial dye concentration values. The experimental equilibrium data for each adsorbent-dye system were successfully fitted to the Langmuir, Freundlich and pH-dependent Langmuir-Freundlich sorption isotherms. Thermodynamic parameters of the adsorption process such as DeltaG degrees, DeltaH degrees, and DeltaS degrees were calculated. The negative values of free energy reflected the spontaneous nature of adsorption. The typical dependence of dye uptake on temperature and the kinetics of adsorption indicated the process to be chemisorption. The grafting modifications greatly enhanced the adsorption performance of the biosorbents, especially in the case of powdered cross-linked chitosan grafted with acrylic acid, which exhibited a maximum adsorption capacity equal to 1.068 mmol/g. Kinetic studies also revealed a significant improvement of sorption rates by the modifications. Diffusion coefficients of the dye molecule were determined to be of the order 10(-13) - 10(-12) m2/s. Furthermore, desorption experiments affirmed the regenerative capability of the loaded material.

  7. Vertical Silicon Nanowires for Image Sensor Applications

    OpenAIRE

    Park, Hyunsung

    2014-01-01

    Conventional image sensors achieve color imaging using absorptive organic dye filters. These face considerable challenges however in the trend toward ever higher pixel densities and advanced imaging methods such as multispectral imaging and polarization-resolved imaging. In this dissertation, we investigate the optical properties of vertical silicon nanowires with the goal of image sensor applications. First, we demonstrate a multispectral imaging system that uses a novel filter that consists...

  8. Development of Highly Soluble Anthraquinone Dichroic Dyes and Their Application to Three-Layer Guest-Host Liquid Crystal Displays

    Directory of Open Access Journals (Sweden)

    Hiroki Iwanaga

    2009-10-01

    Full Text Available The relationships between molecular structures and properties of anthraquinone dichroic dyes were studied and dyes with large solubilities and dichroic ratios were developed. The yellow anthraquinone dye behaves as a quencher of the coumarin dye, and the mixture has a large absorption coefficient without fluorescence. These technologies can enlarge the color reproduction area of three-layer guest-host liquid crystal displays (GHLCDs 1.6-fold. The performances of the prototype reflective three-layer GH-LCDs are as follows: the white state luminous reflectance is 43% and the contrast is 5.3, indicating that they are promising candidates for portable information systems with full-color images.

  9. Chlorine disinfection of dye wastewater: Implications for a commercial azo dye mixture

    Energy Technology Data Exchange (ETDEWEB)

    Vacchi, Francine Inforcato; Albuquerque, Anjaina Fernandes; Vendemiatti, Josiane Aparecida; Morales, Daniel Alexandre [Faculdade de Tecnologia, Universidade Estadual de Campinas, Limeira, SP, 13484-332 (Brazil); Ormond, Alexandra B.; Freeman, Harold S. [Department of Textile Engineering, Chemistry, and Science, North Carolina State University, Raleigh, NC 27695-8301 (United States); Zocolo, Guilherme Juliao; Zanoni, Maria Valnice Boldrin [Departamento de Quimica Analitica, Universidade Estadual Paulista Julio de Mesquita Filho, Instituto de Quimica de Araraquara, Araraquara, SP 14801-970 (Brazil); Umbuzeiro, Gisela, E-mail: giselau@ft.unicamp.br [Faculdade de Tecnologia, Universidade Estadual de Campinas, Limeira, SP, 13484-332 (Brazil)

    2013-01-01

    Azo dyes, the most widely used family of synthetic dyes, are often employed as colorants in areas such as textiles, plastics, foods/drugs/cosmetics, and electronics. Following their use in industrial applications, azo dyes have been found in effluents and various receiving waters. Chemical treatment of effluents containing azo dyes includes disinfection using chlorine, which can generate compounds of varying eco/genotoxicity. Among the widely known commercial azo dyes for synthetic fibers is C.I. Disperse Red 1. While this dye is known to exist as a complex mixture, reports of eco/genotoxicity involve the purified form. Bearing in mind the potential for adverse synergistic effects arising from exposures to chemical mixtures, the aim of the present study was to characterize the components of commercial Disperse Red 1 and its chlorine-mediated decoloration products and to evaluate their ecotoxicity and mutagenicity. In conducting the present study, Disperse Red 1 was treated with chlorine gas, and the solution obtained was analyzed with the aid of LC-ESI-MS/MS to identify the components present, and then evaluated for ecotoxicity and mutagenicity, using Daphnia similis and Salmonella/microsome assays, respectively. The results of this study indicated that chlorination of Disperse Red 1 produced four chlorinated aromatic compounds as the main products and that the degradation products were more ecotoxic than the parent dye. These results suggest that a disinfection process using chlorine should be avoided for effluents containing hydrophobic azo dyes such commercial Disperse Red 1. -- Highlights: Black-Right-Pointing-Pointer Aqueous solutions of Disperse Red 1 were treated with chlorine. Black-Right-Pointing-Pointer The chlorination products of Disperse Red 1 were identified using LC-ESI-MS/MS. Black-Right-Pointing-Pointer Daphnia and Salmonella/microsome were employed for eco/genotoxicity testing. Black-Right-Pointing-Pointer The chlorinated dye was more mutagenic

  10. Optical properties of natural dyes on the dye-sensitized solar cells (DSSC) performance

    Science.gov (United States)

    Pratiwi, D. D.; Nurosyid, F.; Supriyanto, A.; Suryana, R.

    2016-11-01

    This study reported several natural dyes for application in dye-sensitized solar cells (DSSC). This study aims was to determine the effect of optical absorption properties of natural dyes on efficiency of DSSC. The sandwich structure of DSSC consist of TiO2 as working electrode, carbon layer as counter electrode, natural dyes as photosensitizer, and electrolyte as electron transfer media. The natural dyes used in this experiment were extracted from dragon fruit anthocyanin, mangosteen peels anthocyanin, and red cabbage anthocyanin. The absorbance of dyes solutions and the adsorption of the dye on the surface of TiO2 were characterized using UV-Vis spectrophotometer, the quantum efficiency versus wavelength was characterized using incident photon-to-current efficiency (IPCE) measurement system, and the efficiency of DSSC was calculated using I-V meter. UV-Vis characteristic curves showed that wavelength absorption of anthocyanin dye of red cabbage was 450 - 580 nm, anthocyanin of mangosteen peels was 400 - 480 nm, and anthocyanin of dragon fruit was 400 - 650 nm. Absorption spectra of the dye adsorption on the surface of TiO2 which was resulted in the highest absorbance of red cabbage anthocyanin. IPCE characteristic curves with anthocyanin dye of red cabbage, mangosteen peels anthocyanin, and dragon fruit anthocyanin resulted quantum efficiency of 0.058%; 0.047%; and 0.043%, respectively at wavelength maximum about 430 nm. I-V characteristic curves with anthocyanin dye of red cabbage, mangosteen peels anthocyanin, and dragon fruit anthocyanin resulted efficiency of 0.054%; 0.042%; and 0.024%, respectively.

  11. Monitoring excimer formation of perylene dye molecules within PMMA-based nanofiber via FLIM method

    Science.gov (United States)

    Inci, Mehmet Naci; Acikgoz, Sabriye; Demir, Mustafa Muamer

    2016-04-01

    Confocal fluorescence lifetime imaging microscopy method is used to obtain individual fluorescence intensity and lifetime values of aromatic Perylene dye molecules encapsulated into PMMA based nanofibers. Fluorescence spectrum of aromatic hydrocarbon dye molecules, like perylene, depends on the concentration of dye molecules and these dye molecules display an excimeric emission band besides monomeric emission bands. Due to the dimension of a nanofiber is comparable to the monomer emission wavelength, the presence of nanofibers does not become effective on the decay rates of a single perylene molecule and its lifetime remains unchanged. When the concentration of perylene increases, molecular motion of the perylene molecule is restricted within nanofibers so that excimer emission arises from the partially overlapped conformation. As compared to free excimer emission of perylene, time-resolved experiments show that the fluorescence lifetime of excimer emission of perylene, which is encapsulated into NFs, gets shortened dramatically. Such a decrease in the lifetime is measured to be almost 50 percent, which indicates that the excimer emission of perylene molecules is more sensitive to change in the surrounding environment due to its longer wavelength. Fluorescence lifetime measurements are typically used to confirm the presence of excimers and to construct an excimer formation map of these dye molecules.

  12. Performance and stability analysis of curcumin dye as a photo sensitizer used in nanostructured ZnO based DSSC

    Science.gov (United States)

    Sinha, D.; De, D.; Ayaz, A.

    2018-03-01

    Environmental friendly natural dye curcumin extracted from low-cost Curcumina longa stem is used as a photo-sensitizer for the fabrication of ZnO-based dye-sensitized solar cells (DSSC). Nanostructured ZnO is fabricated on a transparent conducting glass (TCO), using a cost-effective chemical bath deposition technique. Scanning electron microscopic images show hexagonal patterned ZnO nano-towers decorated with several nanosteps. The average length of ZnO nano-tower is 5 μm and diameter is 1.2 μm. The UV-Vis spectroscopic study of the curcumin dye is used to understand the light absorption behavior as well as band gap energy of the extracted natural dye. The dye shows wider absorption band-groups over 350-470 nm and 500-600 nm with two peaks positioned at 425 nm and 525 nm. The optical band gap energy and energy band position of the dye is derived which supports its stability and high electron affinity that makes it suitable for light harvesting and effortless electron transfer from dye to the semiconductor or interface between them. FTIR spectrum of curcumin dye-sensitized ZnO-based DSSC shows the presence of anchoring groups and colouring constitutes. The I-V and P-V curves of the fabricated DSSC are measured under simulated light (100 mW/cm2). The highest visible light to electric conversion efficiency of 0.266% (using ITO) and 0.33% (using FTO) is achieved from the curcumin dye-sensitized cell.

  13. Performance and stability analysis of curcumin dye as a photo sensitizer used in nanostructured ZnO based DSSC.

    Science.gov (United States)

    Sinha, D; De, D; Ayaz, A

    2017-12-26

    Environmental friendly natural dye curcumin extracted from low-cost Curcumina longa stem is used as a photo-sensitizer for the fabrication of ZnO-based dye-sensitized solar cells (DSSC). Nanostructured ZnO is fabricated on a transparent conducting glass (TCO), using a cost-effective chemical bath deposition technique. Scanning electron microscopic images show hexagonal patterned ZnO nano-towers decorated with several nanosteps. The average length of ZnO nano-tower is 5μm and diameter is 1.2μm. The UV-Vis spectroscopic study of the curcumin dye is used to understand the light absorption behavior as well as band gap energy of the extracted natural dye. The dye shows wider absorption band-groups over 350-470nm and 500-600nm with two peaks positioned at 425nm and 525nm. The optical band gap energy and energy band position of the dye is derived which supports its stability and high electron affinity that makes it suitable for light harvesting and effortless electron transfer from dye to the semiconductor or interface between them. FTIR spectrum of curcumin dye-sensitized ZnO-based DSSC shows the presence of anchoring groups and colouring constitutes. The I-V and P-V curves of the fabricated DSSC are measured under simulated light (100mW/cm2). The highest visible light to electric conversion efficiency of 0.266% (using ITO) and 0.33% (using FTO) is achieved from the curcumin dye-sensitized cell. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Nucleophilic Addition of Reactive Dyes on Amidoximated Acrylic Fabrics

    Science.gov (United States)

    El-Shishtawy, Reda M.; El-Zawahry, Manal M.; Abdelghaffar, Fatma; Ahmed, Nahed S. E.

    2014-01-01

    Seven reactive dyes judiciously selected based on chemical structures and fixation mechanisms were applied at 2% owf of shade on amidoximated acrylic fabrics. Amidoximated acrylic fabric has been obtained by a viable amidoximation process. The dyeability of these fabrics was evaluated with respect to the dye exhaustion, fixation, and colour strength under different conditions of temperature and dyeing time. Nucleophilic addition type reactive dyes show higher colour data compared to nucleophilic substitution ones. FTIR studies further implicate the binding of reactive dyes on these fabrics. A tentative mechanism is proposed to rationalize the high fixation yield obtained using nucleophilic addition type reactive dyes. Also, the levelling and fastness properties were evaluated for all dyes used. Excellent to good fastness and levelling properties were obtained for all samples irrespective of the dye used. The result of investigation offers a new method for a viable reactive dyeing of amidoximated acrylic fabrics. PMID:25258720

  15. Nucleophilic addition of reactive dyes on amidoximated acrylic fabrics.

    Science.gov (United States)

    El-Shishtawy, Reda M; El-Zawahry, Manal M; Abdelghaffar, Fatma; Ahmed, Nahed S E

    2014-01-01

    Seven reactive dyes judiciously selected based on chemical structures and fixation mechanisms were applied at 2% of of shade on amidoximated acrylic fabrics. Amidoximated acrylic fabric has been obtained by a viable amidoximation process. The dyeability of these fabrics was evaluated with respect to the dye exhaustion, fixation, and colour strength under different conditions of temperature and dyeing time. Nucleophilic addition type reactive dyes show higher colour data compared to nucleophilic substitution ones. FTIR studies further implicate the binding of reactive dyes on these fabrics. A tentative mechanism is proposed to rationalize the high fixation yield obtained using nucleophilic addition type reactive dyes. Also, the levelling and fastness properties were evaluated for all dyes used. Excellent to good fastness and levelling properties were obtained for all samples irrespective of the dye used. The result of investigation offers a new method for a viable reactive dyeing of amidoximated acrylic fabrics.

  16. Adapting vat dye as an alternate dyeing agent for vegetable tanned ...

    African Journals Online (AJOL)

    This experiment was subdivided into three parts where various techniques for applying dyes were used. It proved successful, thus indicating that, with proper formulation, vat dye and its accompanying agents could perform effectively on protein fibre in leatherwork, just as it does on cellulose fibre in textiles.

  17. Disperse Dyes Based on Aminothiophenes: Their Dyeing Applications on Polyester Fabrics and Their Antimicrobial Activity

    Directory of Open Access Journals (Sweden)

    Saleh Mohammed Al-Mousawi

    2013-06-01

    Full Text Available A series of monoazo disperse dyes derived from arylazothienopyridazines were synthesized. Fastness properties of dyed polyester samples were measured. Most of the dyed fabrics tested displayed excellent washing and perspiration fastness and moderate light fastness. Finally, the biological activity of the synthesized dyes against Gram positive bacteria, Gram negative bacteria and yeast were evaluated.

  18. Acid-base indicator properties of dyes from local plants I: Dyes from ...

    African Journals Online (AJOL)

    DR. MIKE HORSFALL

    ABSTRACT: The acid-base indicator properties of aqueous and ethanol extracts from calyces of H. sabdariffa (Zobo) and a dye obtained from the ripe fruits of Basella alba (Indian spinach), two local plants, were investigated. A purple coloured dye obtained from the ripe fruits of Basella alba showed a λmax at. 580nm ...

  19. Isolation and screening of azo dye decolorizing bacterial isolates from dye-contaminated textile wastewater

    Directory of Open Access Journals (Sweden)

    Shahid Mahmood

    2011-04-01

    Full Text Available Azo dyes are released into wastewater streams without any pretreatment and pollute water and soilenvironments. To prevent contamination of our vulnerable resources, removal of these dye pollutants is of greatimportance. For this purpose, wastewater samples were collected from dye-contaminated sites of Faisalabad. About200 bacterial isolates were isolated through enrichment and then tested for their potential to remove RemazolBlack-B azo dye in liquid medium. Five bacterial isolates capable of degrading Remazol Black-B azo dye efficientlywere screened through experimentation on modified mineral salt medium. Isolate SS1 (collected from wastewater ofSupreme Textile Industry was able to completely remove the Remazol Black-B dye from the liquid medium in 18 h.Further, the isolate showed the best performance at the dye concentration of 100 mg L-1 medium (pH 7 and attemperature 35oC. Similarly, yeast extract proved to be the best carbon source for decolorization purpose. Theresults imply that the isolate SS1 could be used for the removal of the reactive dyes from textile effluents.

  20. Reactive dye extraction utilizing regenerated bleaching earth

    Directory of Open Access Journals (Sweden)

    M. Shahi

    2017-09-01

    Full Text Available Bentonite bleaching earth is utilized for purifying used motor oil through a recovery process in order to improve the quality and stability of the final product. Indeed, spent bleaching earth is generated due to adsorbing oil impurities. Polluted spent bleaching earth contains 20-40% (w/w oil and is flammable. Its disposal without pre-treatment leads to loss of oil along with environmental impacts. Accordingly, similar studies have been conducted since 1979 until now. This research was a laboratory study on reactive dye adsorption. Cleaning bleaching clay, thermal remediation and acid washing activation methods were utilized. Response surface methodology was used to design the experiments and determine the optimal parameters in order to run the dye adsorption process. The main experimental parameters have been concluded as temperature (200-800 °C, acid solution concentration (0.1-3 M, dye solution concentration (1-35 ppm, and ratio of activated earth to dye solution (0.1-2 %, w/w. Results revealed that dye adsorption process along with oil removal at a temperature of 650 °C, acid solution concentration of 0.83 M, dye solution concentration of 11.75 ppm and ratio of activated earth to dye solution of 1.52 % (w/w results in an adsorption efficiency of 68.57%. This removal efficiency is a bit higher than activated virgin bleaching earth and much higher than virgin bleaching earth, which has adsorption capacities of 66.75% and 51.56%, respectively. Considering this recycling process, the purified material is quite acceptable technically, environmentally and economically.

  1. An electro-optical and electron injection study of benzothiazole-based squaraine dyes as efficient dye-sensitized solar cell materials: a first principles study.

    Science.gov (United States)

    Al-Fahdan, Najat Saeed; Asiri, Abdullah M; Irfan, Ahmad; Basaif, Salem A; El-Shishtawy, Reda M

    2014-12-01

    Squaraine dyes have attracted significant attention in many areas of daily life from biomedical imaging to semiconducting materials. Moreover, these dyes are used as photoactive materials in the field of solar cells. In the present study, we investigated the structural, electronic, photophysical, and charge transport properties of six benzothiazole-based squaraine dyes (Cis-SQ1-Cis-SQ3 and Trans-SQ1-Trans-SQ3). The effect of electron donating (-OCH3) and electron withdrawing (-COOH) groups was investigated intensively. Ground state geometry and frequency calculations were performed by applying density functional theory (DFT) at B3LYP/6-31G** level of theory. Absorption spectra were computed in chloroform at the time-dependent DFT/B3LYP/6-31G** level of theory. The driving force of electron injection (ΔG (inject)), relative driving force of electron injection (ΔG r (inject)), electronic coupling constants (|VRP|) and light harvesting efficiency (LHE) of all six compounds were calculated and compared with previously studied sensitizers. The ΔG (inject), ΔG r (inject) and |VRP| of all six compounds revealed that these sensitizers would be efficient dye-sensitized solar cell materials. Cis/Trans-SQ3 exhibited superior LHE as compared to other derivatives. The Cis/Trans geometric effect was studied and discussed with regard to electro-optical and charge transport properties.

  2. Review of Recent Progress in Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Fan-Tai Kong

    2007-01-01

    Full Text Available We introduced the structure and the principle of dye-sensitized solar cell (DSC. The latest results about the critical technology and the industrialization research on dye-sensitized solar cells were reviewed. The development of key components, including nanoporous semiconductor films, dye sensitizers, redox electrolyte, counter electrode, and conducting substrate in dye-sensitized solar cells was reviewed in detail. The developing progress and prospect of dye-sensitized solar cells from small cells in the laboratory to industrialization large-scale production were reviewed. At last, the future development of DSC was prospective for the tendency of dye-sensitized solar cells.

  3. Physical and chemical investigations on natural dyes

    Science.gov (United States)

    Acquaviva, S.; D'Anna, E.; de Giorgi, M. L.; Della Patria, A.; Baraldi, P.

    2010-09-01

    Natural dyes have been used extensively in the past for many purposes, such us to colour fibers and to produce inks, watercolours and paints, but their use declined rapidly after the discovery of synthetic colours. Nowadays we witness a renewed interest, as natural dyes are neither toxic nor polluting. In this work, physical and chemical properties of four selected dyes, namely red (Madder), yellow (Weld and Turmeric) and blue (Woad) colours, produced by means of traditional techniques at the Museo dei Colori Naturali (Lamoli, Italy), have been investigated. The chromatic properties have been studied through the reflectance spectroscopy, a non-invasive technique for the characterisation of chromaticity. Reflection spectra both from powders and egg-yolk tempera models have been acquired to provide the typical features of the dyes in the UV-vis spectral range. Moreover, to assess the feasibility of laser cleaning procedures, tempera layers were investigated after irradiation with an excimer laser. Micro Raman spectroscopy, Scanning Electron Microscopy and Energy Dispersive X-Ray analyses have complemented the survey, returning compositional and morphological information as well. Efforts have been made to give scientific feedback to the production processes and to support the research activity in the restoration of the artworks where these dyes were employed.

  4. Chromed Leather Dyeing Peculiarities when Deliming with Peracetic Acid

    Directory of Open Access Journals (Sweden)

    Kęstutis BELEŠKA

    2013-05-01

    Full Text Available The research was aimed to investigate the influence of deliming with peracetic acid on leather dyeing kinetics. Hydrophobic C.I. Acid Red 213 and hydrophilic C.I. Acid Red 423 dyes were used. Sorption of dye depends on hydrophobicity/hydrophility of dye and dyeing temperature. Equilibrium of process is reached faster using hydrophobic C.I. Acid Red 213 at 45 ºC. However, both control and experimental leather fibres adsorb more hydrophilic dye C.I. Acid Red 423 and this fact does not depend on temperature. The diffusion coefficient of dye C.I. Acid Red 423 calculated according to Weisz model is higher when dyeing conventional leather. The change of deliming method has influence on chromed leather dyeing but this influence is not significant. The adsorption ability of control leather fibres at 30 ºC and 45 ºC is higher using both dyes as compared to the dyeing the experimental one. The increase of dyeing temperature increases the adsorption ability independently on the sort of leather fibres. Such dependence of the adsorption ability on the temperature shows that hydrophobic action and van der Waals forces prevail between dye and fibres during dyeing process. The Gibbs energy changes show that adsorption of both dyes by leather fibres independently on their sort is a spontaneous process. The affinity of both dyes to conventional leather fibres is higher comparing with experimental one. The change of enthalpy is positive in all cases, and it means that the driving force of the dyeing is the change of entropy.DOI: http://dx.doi.org/10.5755/j01.ms.19.2.4431

  5. Quantum dot-dye hybrid systems for energy transfer applications

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Ting

    2010-07-01

    In this thesis, we focus on the preparation of energy transfer-based quantum dot (QD)-dye hybrid systems. Two kinds of QD-dye hybrid systems have been successfully synthesized: QD-silica-dye and QD-dye hybrid systems. In the QD-silica-dye hybrid system, multishell CdSe/CdS/ZnS QDs were adsorbed onto monodisperse Stoeber silica particles with an outer silica shell of thickness 2-24 nm containing organic dye molecules (Texas Red). The thickness of this dye layer has a strong effect on the total sensitized acceptor emission, which is explained by the increase in the number of dye molecules homogeneously distributed within the silica shell, in combination with an enhanced surface adsorption of QDs with increasing dye amount. Our conclusions were underlined by comparison of the experimental results with Monte-Carlo simulations, and by control experiments confirming attractive interactions between QDs and Texas Red freely dissolved in solution. New QD-dye hybrid system consisting of multishell QDs and organic perylene dyes have been synthesized. We developed a versatile approach to assemble extraordinarily stable QD-dye hybrids, which uses dicarboxylate anchors to bind rylene dyes to QD. This system yields a good basis to study the energy transfer between QD and dye because of its simple and compact design: there is no third kind of molecule linking QD and dye; no spacer; and the affinity of the functional group to the QD surface is strong. The FRET signal was measured for these complexes as a function of both dye to QD ratio and center-to-center distance between QD and dye by controlling number of covered ZnS layers. Data showed that fluorescence resonance energy transfer (FRET) was the dominant mechanism of the energy transfer in our QD-dye hybrid system. FRET efficiency can be controlled by not only adjusting the number of dyes on the QD surface or the QD to dye distance, but also properly choosing different dye and QD components. Due to the strong stability, our QD-dye

  6. Effect of Mixing Dyes and Solvent in Electrolyte Toward Characterization of Dye Sensitized Solar Cell Using Natural Dyes as The Sensitizer

    Science.gov (United States)

    Puspitasari, Nurrisma; Nurul Amalia, Silviyanti S.; Yudoyono, Gatut; Endarko

    2017-07-01

    Dye Sensitized Solar Cell (DSSC) using natural dyes (chlorophyll, curcumin from turmeric extract, and anthocyanin from mangosteen extract) have been successfully fabricated for determining the effect of variation natural dyes, mixing dyes and acetonitrile in electrolyte toward characterization of DSSC. DSSC consists of five parts namely ITO (Indium Tin Oxide) as a substrate; TiO2 as semiconductor materials; natural dyes as an electron donor; electrolyte as electron transfer; and carbon as a catalyst that can convert light energy into electric energy. Two types of gel electrolyte based on PEG that mixed with liquid electrolyte have utilized for analyzing the lifetime of DSSC. Type I used distilled water as a solvent whilst type II used acetonitrile as a solvent with addition of concentration of KI and iodine. The main purpose of study was to investigate influence of solvent in electrolyte, variation of natural dyes and mixing dyes toward an efficiency that resulted by DSSC. The result showed that electrolyte type II is generally better than type I with efficiency 0,0556 and 0,0456 %, respectively. An efficiency values which resulted from a variation of mixed three natural dyes showed the greatest efficiency compared to mixed two natural dyes and one dye, with an efficiency value can be achieved at 0,0194 % for chlorophyll; 0,111 % for turmeric; 0,0105 % for mangosteen; 0,0244% (mangosteen and chlorophyll); 0,0117 % (turmeric and mangosteen); 0,0158 % (turmeric and chlorophyll); and 0.0566 % (mixed three natural dyes).

  7. Clinical approved fluorescent dyes coupled to endomicroscopy for in vivo diagnostic of peritoneal carcinomatosis

    Science.gov (United States)

    Abbaci, Muriel; Dartigues, Peggy; Soufan, Ranya; De Leeuw, Frederic; Fabre, Monique; Laplace-Builhé, Corinne

    2015-03-01

    Peritoneal carcinomatosis is metastatic stage aggravating digestive, gynecological or bladder cancer dissemination and the preoperative evaluation of lesions remains difficult. There is therefore a need for minimal invasive innovative techniques to establish a precise preoperative assessment of cancer peritoneal cavity. Probe-based confocal laser endomicroscopy (pCLE) provides dynamic images of the microarchitecture of tissues during an endoscopy. The PERSEE project proposes new developments in robotics and pCLE for the exploration of the peritoneal cavity during laparoscopy. Two fluorescent dyes, Patent blue V and Indocyanine green have been evaluated on human ex vivo samples to improve the contrast of pCLE images. For a future implementation in clinical study, two topically staining protocols operable in vivo have been validated on 70 specimens from 25 patients with a peritoneal carcinomatosis. The specimens were then imaged by pCLE with an optical probe designed for the application. A histo-morphological correlative study was performed on 350 pCLE images and 70 standard histological preparations. All images were interpreted in a random way by two pathologists. Differential histological diagnostics such as normal peritoneum or pseudomyxoma could be recognized on fluorescence images. The statistical analysis of the correlative study is underway. These dyes already approved for human use are interesting for pCLE imaging because some micromorphological criteria look like to conventional histology and are readable by pathologist. Thus pCLE images using both dyes do not require a specific semiology unlike to what is described in the literature, for pCLE associated with fluorescein for the in vivo imaging of pancreatic cysts.

  8. In-situ Decolorization of Residual Dye Effluent in Textile Jet Dyeing Machine by Ozone

    Directory of Open Access Journals (Sweden)

    Irfan Ahmed Shaikh

    2014-12-01

    Full Text Available In this study, a new idea of decolourization was investigated in which residual dyeing effluent from textile dyeing process was treated using O3 in the same machine where it was generated. The novelty comes from the idea of doing dyeing and treatment simultaneously. At the completion of dyeing process, O3 gas was injected directly into the machine to remove colour and COD from the wastewater. To evaluate the effectiveness of new method, pilot-scale studies were performed, and decolourization of residual dyeing effluents containing C.I. Reactive Orange 7, C.I. Reactive Blue 19, and C.I. Reactive Black 5 was carried out in specially built textile jet dyeing machine. The results showed that almost 100% colour removal and 90% COD reduction were achieved when process conditions such as pH, dye concentration (mg/L, ozone production rate (g/hr, and temperature were optimized. The study concludes that new method has a great potential to eliminate the need of a separate end-of-the-pipe wastewater treatment system, thus offering an on-site and cost-effective solution.

  9. Dyeing of Silk with Anthocyanins Dyes Extract from Liriope platyphylla Fruits

    Directory of Open Access Journals (Sweden)

    Huayin Wang

    2014-01-01

    Full Text Available A new source of natural anthocyanins dyes, from Liriope platyphylla fruit, is proposed. This paper analyzes the dye extracts, the primary color components of the extracts, the color features of the extracts under different pH conditions, and their application in silk dyeing. The research shows that, nine anthocyanins are found in  L. platyphylla fruits by analyzing the results of the HPLC/DAD, MS, and MS/MS spectra. The five major anthocyanins related to delphinidin, petunidin, and malvidin derivatives take up 91.72% of total anthocyanin contents. The color of the solution is red under acidic condition (pH < 3.0 and stays in yellow under alkaline condition with pH values above 7.0. The dye extracts applied to silk fabric with mordant free dyeing show different color under different pH conditions, changing between purple, blue, green, and yellow. However, the dyed colors is light and the dyeing rate is low. Metal mordant such as Sn in chelation enhances the dye depth and improves the fastness of the dyed silk fabrics, especially in silk fabrics dyed by premordanting and metamordanting.

  10. Comparison of Ca2+ transients and [Ca2+]i in the dendrites and boutons of non-fast-spiking GABAergic hippocampal interneurons using two-photon laser microscopy and high- and low-affinity dyes

    Science.gov (United States)

    Kisfali, Máté; Lőrincz, Tibor; Vizi, E Sylvester

    2013-01-01

    Using two-photon laser microscopy, high- and low-affinity dyes and patch clamp electrophysiology, we successfully measured somatic stimulation-evoked Ca2+ transients simultaneously in the dendrites and axonal boutons of the same non-fast-spiking GABAergic interneurons in acute slice preparations obtained from hippocampal area CA1. The advantage of the acute preparation is that both neuronal connections and anatomy are maintained. Calculated as unperturbed values, the amplitudes of Ca2+ transients and changes in [Ca2+]i in response to somatic single or burst stimulation were much higher in boutons (428 nm/AP) than in dendrites (49 nm/AP), leading to the conclusion that the much greater influx of Ca2+ observed in terminals might be due to a higher density of N-type voltage-sensitive Ca2+ channels compared to the L-type channels present in dendrites. Whereas the decay of Ca2+ transients recorded in dendrites was primarily mono-exponential, the decay in boutons was bi-exponential, as indicated by an initial fast phase, followed by a much slower reduction in fluorescence intensity. The extrusion of Ca2+ was much faster in boutons than in dendrites. To avoid saturation effects and the flawed conversion of fluorescence measures of [Ca2+]i, we assessed the limits of [Ca2+] measurements (which ranged between 6 and 82% of the applied dye saturation) when high- and low-affinity dyes were applied at different concentrations. When two APs were delivered at a high frequency (>3 Hz) of stimulation, the low-affinity indicators OGB-6F (KD= 3.0 μm) and OGB-5N (KD= 20 μm) were able to accurately reflect the changes in ΔF/F produced by the consecutive APs. There was no difference in the endogenous buffer capacity (κE), which can shape Ca2+ signals, calculated in dendrites (κE= 354) or boutons (κE= 458). PMID:23981718

  11. Light-Up "Channel Dyes" for Haloalkane-Based Protein Labeling in Vitro and in Bacterial Cells.

    Science.gov (United States)

    Clark, Spencer A; Singh, Vijay; Vega Mendoza, Daniel; Margolin, William; Kool, Eric T

    2016-12-21

    We describe a novel molecular strategy for engendering a strong light-up signal in fluorescence tagging of the genetically encoded HaloTag protein domain. We designed a set of haloalkane-derivatized dyes having twisted internal charge transfer (TICT) structures potentially narrow enough to partially fit into the enzyme's haloalkane-binding channel. Testing a range of short chain lengths revealed a number of active dyes, with seven carbons yielding optimum light-up signal. The dimethylaminostilbazolium chloroheptyl dye (1d) yields a 27-fold fluorescence emission enhancement (λex = 535 nm; Em(max) = 616 nm) upon reaction with the protein. The control compound with standard 12-atom linkage shows less efficient signaling, consistent with our channel-binding hypothesis. For emission further to the red, we also prepared a chloroheptyl naphthalene-based dye; compound 2 emits at 653 nm with strong fluorescence enhancement upon reaction with the HaloTag domain. The two dyes (1d, 2) were successfully tested in wash-free imaging of protein localization in bacteria, using a HaloTag fusion of the filamenting temperature-sensitive mutant Z (FtsZ) protein in Escherichia coli (E. coli). The new dye conjugates are inexpensive and easily synthesized enzyme substrates with low background and large Stokes shifts, offering substantial benefits over known fluorescent substrates for the HaloTag enzyme.

  12. Effectiveness of dye sensitised solar cell under low light condition using wide band dye

    Energy Technology Data Exchange (ETDEWEB)

    Sahmer, Ahmad Zahrin, E-mail: ahmadzsahmer@gmail.com; Mohamed, Norani Muti, E-mail: noranimuti-mohamed@petronas.com.my; Zaine, Siti Nur Azella, E-mail: ct.azella@gmail.com [Universiti Teknologi PETRONAS, Bandar Seri Iskandar, 31750 Tronoh, Perak (Malaysia)

    2015-07-22

    Dye sensistised solar cell (DSC) based on nanocrystalline TiO{sub 2} has the potential to be used in indoor consumer power application. In realizing this, the DSC must be optimized to generate power under low lighting condition and under wider visible light range. The use of wide band dye N749 which has a wider spectrum sensitivity increases the photon conversion to electron between the visible light spectrums of 390nm to 700nm. This paper reports the study on the effectiveness of the dye solar cell with N749 dye under low light condition in generating usable power which can be used for indoor consumer application. The DSC was fabricated using fluorine doped tin oxide (FTO) glass with screen printing method and the deposited TiO{sub 2} film was sintered at 500°C. The TiO{sub 2} coated FTO glass was then soaked in the N749 dye, assembled into test cell, and tested under the standard test condition at irradiance of 1000 W/m{sup 2} with AM1.5 solar soaker. The use of the 43T mesh for the dual pass screen printing TiO{sub 2} paste gives a uniform TiO{sub 2} film layer of 16 µm. The low light condition was simulated using 1/3 filtered irradiance with the solar soaker. The fabricated DSC test cell with the N749 dye was found to have a higher efficiency of 6.491% under low light condition compared to the N719 dye. Under the standard test condition at 1 sun the N749 test cell efficiency is 4.55%. The increases in efficiency is attributed to the wider spectral capture of photon of the DSC with N749 dye. Furthermore, the use of N749 dye is more effective under low light condition as the V{sub OC} decrement is less significant compared to the latter.

  13. Third row metal complexes as an alternative dye in dye sensitized solar cell system

    Science.gov (United States)

    Wahyuningsih, S.; Ramelan, A. H.; Badriyah, I.; Kristy, I. O.; Dewi, N. S.; Rahardjo, S. B.

    2013-10-01

    Copper(II), Cobalt (II) and Iron (II) complexes as photosensitizer on Dye Sensitized Solar Cell (DSSC) had been investigated. The aim of this research is to find out the respond addition of those dyes on FTO/TiO2 (FTO = fluorine Tin Oxide) thin film to visible light and the effect of various third row complexes to DSSC performance. Slip casting method was used to fabricate FTO/TiO2 and FTO/carbon thin film. The result from FTO/TiO2 UV-Vis spectra show no absorption on visible light. Dye solution was synthesized from free metal ions of Cu(II), Co(II), and Fe(II) in methanol with diphenylamine (dpa), 2,2,bypiridine (bpy), 1,10, phenathroline (phen), 4,4'-dicarboxylic acid-2,2'-bipyridine (dcbq), and anthocyanin (ant) ligands, respectively. UV-Vis spectrophotometry was used to identify FTO/TiO2/dye with various sensitizer dyes. The performance of DSSC was determined by I (current) - V (voltage) curve using Keithley 2602 A System Source. In this research, DSSCs are able to convert photon energy become electrical energy. Dye used in DSSC is greatly effect in photon to current efficiency (IPCE). The greater absorption in visible region of alternative dye used gains higher IPCE spectra. TiO2 character can help spread the absorption in whole visible region. The nanosize mesoporous TiO2 of TiO2/SiPA/CoII-PAR (SiPA = silylpropilamine) have greater value than P25 TiO2/SiPA-CoII-PAR. The SiPA/FeII-PAR and SiPA/CoII-PAR dyes are better dye than tpa.

  14. Oxidative degradation of azo dyes using tourmaline.

    Science.gov (United States)

    Wang, Cuiping; Zhang, Yanwei; Yu, Li; Zhang, Zhiyuan; Sun, Hongwen

    2013-09-15

    This study aimed to investigate the catalyzed degradation ability of tourmaline on the dyes methylene blue (MB), rhodamine B (RhB), and congo red (CR) at different pH values. Interestingly, tourmaline strongly adsorbed anionic dyes, but it did not adsorb cationic dyes. When H₂O₂ was introduced into the tourmaline-dye systems, the degradation percentage for CR catalysis by tourmaline was lower than the percentage of adsorption, whereas the opposite was true for MB and RhB systems. Notably, the catalyzed degradation decreased from 100% to 45% for MB, 100% to 15% for RhB and 100% to 25% for CR as the pH increased from 3.0 to 10.0, respectively, which was much greater than the degradation obtained for previously reported materials at pH values ranging from 4.0 to 10.0. Tourmaline catalytically degraded the dyes over a broad range of pH values, which was attributed to tourmaline automatically adjusting the pH of the dye solutions to approximately 5.5 from an initial range of 4.2-10.0. An electron paramagnetic resonance spin trapping technique observed peroxyl (ROO·) and alkoxy (RO·) or alkyl (R·) radicals originated from the attack of ·OH radicals and O₂(·-) radicals, indicating that these radicals were involved in the catalyzed degradation of MB. Importantly, four intermediate products of MB at m/z 383, 316, 203 and 181 were observed by LC/MS. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Continuous-wave organic dye lasers and methods

    Energy Technology Data Exchange (ETDEWEB)

    Shapira, Ofer; Chua, Song-Liang; Zhen, Bo; Lee, Jeongwon; Soljacic, Marin

    2014-09-16

    An organic dye laser produces a continuous-wave (cw) output without any moving parts (e.g., without using flowing dye streams or spinning discs of solid-state dye media to prevent photobleaching) and with a pump beam that is stationary with respect to the organic dye medium. The laser's resonant cavity, organic dye medium, and pump beam are configured to excite a lasing transition over a time scale longer than the associated decay lifetimes in the organic dye medium without photobleaching the organic dye medium. Because the organic dye medium does not photobleach when operating in this manner, it may be pumped continuously so as to emit a cw output beam. In some examples, operation in this manner lowers the lasing threshold (e.g., to only a few Watts per square centimeter), thereby facilitating electrical pumping for cw operation.

  16. Novel Tunable Dye Laser for Lidar Detection Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A tunable dye laser for Lidar detection will be fabricated based on the innovative dye-doped Holographic Polymer Dispersed Liquid Crystals (HPDLC) technology. The...

  17. Continuous-wave organic dye lasers and methods

    Science.gov (United States)

    Shapira, Ofer; Chua, Song-Liang; Zhen, Bo; Lee, Jeongwon; Soljacic, Marin

    2014-09-16

    An organic dye laser produces a continuous-wave (cw) output without any moving parts (e.g., without using flowing dye streams or spinning discs of solid-state dye media to prevent photobleaching) and with a pump beam that is stationary with respect to the organic dye medium. The laser's resonant cavity, organic dye medium, and pump beam are configured to excite a lasing transition over a time scale longer than the associated decay lifetimes in the organic dye medium without photobleaching the organic dye medium. Because the organic dye medium does not photobleach when operating in this manner, it may be pumped continuously so as to emit a cw output beam. In some examples, operation in this manner lowers the lasing threshold (e.g., to only a few Watts per square centimeter), thereby facilitating electrical pumping for cw operation.

  18. The Ideal Solvent for Paper Chromatography of Food Dyes.

    Science.gov (United States)

    Markow, Peter G.

    1988-01-01

    Uses paper chromatography with food dyes to provide a simple and inexpensive basis for teaching chromatography. Provides experimental methodology and tabled results. Includes a solvent system comparison (Rf) for seven dyes and twenty-two solvents. (MVL)

  19. Unconsumed precursors and couplers after formation of oxidative hair dyes

    DEFF Research Database (Denmark)

    Rastogi, Suresh Chandra; Søsted, Heidi; Johansen, Jeanne Duus

    2006-01-01

    Contact allergy to hair dye ingredients, especially precursors and couplers, is a well-known entity among consumers having hair colouring done at home or at a hairdresser. The aim of the present investigation was to estimate consumer exposure to some selected precursors (p-phenylenediamine, toluene......-2,5-diamine) and couplers (3-aminophenol, 4-aminophenol, resorcinol) of oxidative hair dyes during and after hair dyeing. Concentrations of unconsumed precursors and couplers in 8 hair dye formulations for non-professional use were investigated, under the conditions reflecting hair dyeing. Oxidative...... hair dye formation in the absence of hair was investigated using 6 products, and 2 products were used for experimental hair dyeing. In both presence and absence of hair, significant amounts of unconsumed precursors and couplers remained in the hair dye formulations after final colour development. Thus...

  20. Natural dye extract of lawsonia inermis seed as photo sensitizer for titanium dioxide based dye sensitized solar cells

    Science.gov (United States)

    Ananth, S.; Vivek, P.; Arumanayagam, T.; Murugakoothan, P.

    2014-07-01

    Natural dye extract of lawsonia inermis seed were used as photo sensitizer to fabricate titanium dioxide nanoparticles based dye sensitized solar cells. Pure titanium dioxide (TiO2) nanoparticles in anatase phase were synthesized by sol-gel technique and pre dye treated TiO2 nanoparticles were synthesized using modified sol-gel technique by mixing lawsone pigment rich natural dye during the synthesis itself. This pre dye treatment with natural dye has yielded colored TiO2 nanoparticles with uniform adsorption of natural dye, reduced agglomeration, less dye aggregation and improved morphology. The pure and pre dye treated TiO2 nanoparticles were subjected to structural, optical, spectral and morphological studies. Dye sensitized solar cells (DSSC) fabricated using the pre dye treated and pure TiO2 nanoparticles sensitized by natural dye extract of lawsonia inermis seed showed a promising solar light to electron conversion efficiency of 1.47% and 1% respectively. The pre dye treated TiO2 based DSSC showed an improved efficiency of 47% when compared to that of conventional DSSC.

  1. Spatiotemporal Profiles of Proprioception Processed by the Masseter Muscle Spindles in Rat Cerebral Cortex: An Optical Imaging Study.

    Science.gov (United States)

    Fujita, Satoshi; Kaneko, Mari; Nakamura, Hiroko; Kobayashi, Masayuki

    2017-01-01

    Muscle spindles in the jaw-closing muscles, which are innervated by trigeminal mesencephalic neurons (MesV neurons), control the strength of occlusion and the position of the mandible. The mechanisms underlying cortical processing of proprioceptive information are critical to understanding how sensory information from the masticatory muscles regulates orofacial motor function. However, these mechanisms are mostly unknown. The present study aimed to identify the regions that process proprioception of the jaw-closing muscles using in vivo optical imaging with a voltage-sensitive dye in rats under urethane anesthesia. First, jaw opening that was produced by mechanically pulling down the mandible evoked an optical response, which reflects neural excitation, in two cortical regions: the most rostroventral part of the primary somatosensory cortex (S1) and the border between the ventral part of the secondary somatosensory cortex (S2) and the insular oral region (IOR). The kinetics of the optical signal, including the latency, amplitude, rise time, decay time and half duration, in the S1 region for the response with the largest amplitude were comparable to those in the region with the largest response in S2/IOR. Second, we visualized the regions responding to electrical stimulation of the masseter nerve, which activates both motor efferent fibers and somatosensory afferent fibers, including those that transmit nociceptive and proprioceptive information. Masseter nerve stimulation initially excited the rostral part of the S2/IOR region, and an adjacent region responded to jaw opening. The caudal part of the region showing the maximum response overlapped with the region responding to jaw opening, whereas the rostral part overlapped with the region responding to electrical stimulation of the maxillary and mandibular molar pulps. These findings suggest that proprioception of the masseter is processed in S1 and S2/IOR. Other sensory information, such as nociception, is

  2. RISK ASSESSMENT FOR THE DYE AND PIGMENT ...

    Science.gov (United States)

    This risk assessment calculates the maximum loadings of constituents found in dyes and pigment industries waste streams which can be disposed in different types of waste management units without causing health benchmarks to be exceeded at plausible receptor locations. The assessment focuses on potential risks from volatilization and leaching to groundwater of constituents disposed in surface impoundments and landfills with either clay liners or composite liners. This product will be used by EPA decision makers to assist in determining whether certain waste streams generated by the dyes and pigments industries should be designated as hazardous.

  3. Tunability of optofluidic distributed feedback dye lasers

    DEFF Research Database (Denmark)

    Gersborg-Hansen, Morten; Kristensen, Anders

    2007-01-01

    We investigate the tunability of optofluidic distributed feedback (DFB) dye lasers. The lasers rely on light-confinement in a nano-structured polymer film where an array of nanofluidic channels constitutes a third order Bragg grating DFB laser resonator with a central phase-shift. The lasers...... are operated by filling the DFB laser resonator with a dye solution by capillary action and optical pumping with a frequency doubled Nd: YAG laser. The low reflection order of the DFB laser resonator yields low out-of-plane scattering losses as well as a large free spectral range (FSR), and low threshold...

  4. Waste Water Treatment of Dye Contamination

    Directory of Open Access Journals (Sweden)

    Pattana Boonyaprapa

    2009-01-01

    Full Text Available The objectives of this research were to study tie-dye process data and wastewater characteristics from 60 entrepreneurs, and to study the colour density treatment in pilot scale by using upflow anaerobic filters. From 60 filled-out questionnaires, it was found that all tie-dye entrepreneurs used reactive dyes by a hot method. Ninety-eight percent of the tie-dye enterpreneurs produced wastewater at the rate of not more than 1500 liters per day. All of them lacked tie-dye wastewater treatment systems. Eighty-five percent of tie-dye entrepreneurs agreed that there must be wastewater treatment before release into the environment. From group discussions, it was found that the entrepreneurs realized the wastewater problem and wanted to carry out environment friendly tie-dyeing. Our study demonstrated that the average value of the colour density, chemical oxygen demand (COD, total dissolved solids (TDS and pH of the wastewater characteristics were 170 SU (space units, 1584 mg/l, 2487 mg/l and 8, respectively. For the upflow anaerobic filter, 5 sets of experiments, with 24 hours retention time, were designed, with 0, 1, 2, 3 and 4 % of cow’s feces ferment, respectively (sets 1st-5th. The result showed decreasing colour densities from 170 SU to 160 SU (dark colour, 60 SU (very light colour, 12 SU (no colour, 10 SU (no colour and 10 SU (no colour, respectively. We conclude that the upflow anaerobic filter, containing 2% cow’s feces ferment is an efficient way to reduce colour density of the wastewater. Mixing cow’s feces ferment with tie-dye wastewater increased COD and TDS in wastewater. Mean COD was increased by residual organic matter from 1584 mg/l (before treatment to (after-treatment, sets 2nd- 5th 1600 mg/l, 1680 mg/l, 1710 mg/l and 1750 mg/l, respectively. COD aftertreatment was higher than the industrial effluence standard (400 mg/l. Further treatment COD might include wetland procedures. TDS was increased by some residual organic matter

  5. A high-light-harvesting-efficiency coumarin dye for stable dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Z.S.; Cui, Y.; Hara, K. [National Institute of Advanced Industrial, Science and Technology (AIST), Tsukuba, Ibaraki (Japan); Dan-oh, Y.; Kasada, C.; Shinpo, A. [Hayashibara Biochemical Laboratories, Inc., Okayama (Japan)

    2007-04-20

    A new coumarin dye for use in dye-sensitized solar cells (DSSCs) is reported. It exhibits near-unity light harvesting efficiency and incident photon-to-electron conversion efficiency over a wide spectral region in 6 {mu}m transparent TiO{sub 2} films. DSSCs based on this metal-free organic dye show long-term stability and power-conversion efficiencies of around 6 % under continuous light-soaking stress for up to 1000 h. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

  6. Red photoluminescence emission of laser dye doped DNA and PMMA

    Science.gov (United States)

    Yu, Zhou; Hagen, Josh A.; Grote, James G.; Steckl, Andrew J.

    2006-02-01

    DNA and PPMA were doped with the laser dye sulforhodamine 640. Red emission was observed from both dye-doped DNA and PMMA upon photoexcitation. Photoluminescence (PL) emission was studied as a function of dye concentration. The maximum PL intensity of dye in DNA host material is at least 17 times higher than that in PMMA. The DNA host shows higher doping concentration without optical quenching than PMMA does.

  7. Removal of textile dyes with biopolymers xanthan and alginic acid

    Energy Technology Data Exchange (ETDEWEB)

    Lozano-Alvarez, J.; Jauregui-Rincon, J.; Mendoza-Diaz, G.; Rodriguez-Vazquez, G.; Frausto-Reyes, C.

    2009-07-01

    Textile industry is an important activity that provides considerable benefits to people, but unfortunately dyeing of yarn and cloth produces pollution of water, a resource that is valuable and scarce. Dyeing of textiles fibers is an inefficient process, in view of the fact that approximately ten percent of total dye is thrown to municipal sewage. Although different treatment systems are applied to wastewater, dyes are resistant to physical, chemical and biological factors because of the way they are designed. (Author)

  8. Development of sustainable dye adsorption system using nutraceutical industrial fennel seed spent-studies using Congo red dye.

    Science.gov (United States)

    Taqui, Syed Noeman; Yahya, Rosiyah; Hassan, Aziz; Nayak, Nayan; Syed, Akheel Ahmed

    2017-07-03

    Fennel seed spent (FSS)-an inexpensive nutraceutical industrial spent has been used as an efficient biosorbent for the removal of Congo red (CR) from aqueous media. Results show that the conditions for maximum adsorption would be pH 2-4 and 30°C were ideal for maximum adsorption. Based on regression fitting of the data, it was determined that the Sips isotherm (R 2 = 0.994, χ 2 = 0.5) adequately described the mechanism of adsorption, suggesting that the adsorption occurs homogeneously with favorable interaction between layers with favorable interaction between layers. Thermodynamic analysis showed that the adsorption is favorable (negative values for ΔG°) and endothermic (ΔH° = 12-20 kJ mol -1 ) for initial dye concentrations of 25, 50, and 100 ppm. The low ΔH° value indicates that the adsorption is a physical process involving weak chemical interactions like hydrogen bonds and van der Waals interactions. The kinetics revealed that the adsorption process showed pseudo-second-order tendencies with the equal influence of intraparticle as well as film diffusion. The scanning electron microscopy images of FSS show a highly fibrous matrix with a hierarchical porous structure. The Fourier transform infrared spectroscopy analysis of the spent confirmed the presence of cellulosic and lignocellulosic matter, giving it both hydrophilic and hydrophobic properties. The investigations indicate that FSS is a cost-effective and efficient biosorbent for the remediation of toxic CR dye.

  9. Integrated and sequential anaerobic/aerobic biodegradation of azo dyes

    NARCIS (Netherlands)

    Tan, N.G.C.

    2001-01-01

    Azo dyes constitute a major class of environmental pollutants accounting for 60 to 70% of all dyes and pigments used. These compounds are characterized by aromatic moieties linked together with azo groups (-N=N-). The release of azo dyes into the environment is a concern due to coloration

  10. Aerobic decolourization of two reactive azo dyes under varying ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-02-01

    Feb 1, 2010 ... colourants; they are usually not easily biodegraded. Dye colours are visible in water at concentration as low as 1 mg/L, whereas textile processing waste water, normally contain more than 10-200 mg/L dye concentration, resulting in aesthetic problems (O'Neil et al., 1999). The toxicity of dye industrial waste ...

  11. Optimization of Crystal Violet dye removal from aqueous solution ...

    African Journals Online (AJOL)

    Batch adsorption process involving use of groundnut shell (GS) and orange peel (OP) as adsorbents was employed for the removal of carcinogenic Crystal Violet dye from aqueous solution. Studies were carried out as function of contact time, sorbent dosage, initial dye concentration and pΗ of the dye solution with a view of ...

  12. Page 1 PRELIMINARY INVESTIGATION OF DYE-ION ...

    African Journals Online (AJOL)

    forms were identified. Then acid buffers" and alkaline buffers' of appropriate pH values were prepared for use with each dye. A typical potentiometric titration result for a dye is shown in Fig. 1 for bromopyrogallol red while the dependence of its absorbance on pH is shown in Fig. 2. Stable pH values for the listed dyes are.

  13. Biotreatment of anthraquinone dye Drimarene Blue K2RL

    African Journals Online (AJOL)

    ISHIOMA

    Drimarene Blue (Db) K2RL is a reactive anthraquinone dye, used extensively in textile industry, due to poor adsorbability to textile fiber; it has a higher exhaustion rate in wastewater. The dye is toxic, carcinogenic, mutagenic and resistant to degradation. Decolorization of this dye was studied in two different systems.

  14. Fluorescence of dyes adsorbed on highly organized nanostructured gold surfaces

    NARCIS (Netherlands)

    Levi, S.; Mourran, Ahmed; Spatz, Joachim P.; van Veggel, F.C.J.M.; Reinhoudt, David; Möller, M.

    2002-01-01

    It is shown that fluorescent dyes can be adsorbed selectively on gold nanoparticles which are immobilized on a glass substrate and that the fluorescence originating from the adsorbed dyes exhibits significantly less quenching when compared to dyes adsorbed on bulk gold. Self-assembled monolayers of

  15. Comparison of dye decolorization efficiencies of indigenous fungal ...

    African Journals Online (AJOL)

    Different physicochemical cultural conditions were optimized for azo dye removal by using Acid Red 151 as a model dye, being of high consumer demand and usage during the present study. The three fungal strains having the dye removal abilities, Aspergillus niger SA1, Aspergillus flavus SA2 and Aspergillus terreus SA3 ...

  16. Synthesis and application of hetaryl disazo disperse dyes derived ...

    African Journals Online (AJOL)

    Also, it was found that the wash fastness property, which is an indicator whether a dye could have affinity for a textile fabric or not, have excellent ratings of 5. From these results, it can be concluded that the best of these disazo dye compounds could be commercially important in the textile industry. Keywords: Disazo dyes ...

  17. 40 CFR 721.9717 - Azo monochloro triazine reactive dye.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Azo monochloro triazine reactive dye... Substances § 721.9717 Azo monochloro triazine reactive dye. (a) Chemical substance and significant new uses... reactive dye (PMN P-96-238) is subject to reporting under this section for the significant new uses...

  18. 40 CFR 721.2527 - Substituted diphenylazo dye (generic name).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted diphenylazo dye (generic... Specific Chemical Substances § 721.2527 Substituted diphenylazo dye (generic name). (a) Chemical substance... substituted diphenylazo dye (PMN P-95-514) is subject to reporting under this section for the significant new...

  19. 40 CFR 721.5915 - Polysubstituted phenylazopolysubstitutedphenyl dye.

    Science.gov (United States)

    2010-07-01

    ... phenylazopolysubstitutedphenyl dye. 721.5915 Section 721.5915 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.5915 Polysubstituted phenylazopolysubstitutedphenyl dye. (a) Chemical... as a polysubstituted phenylazopolysubstitutedphenyl dye (PMN P-93-658) is subject to reporting under...

  20. 40 CFR 721.5917 - Phenyl azo dye (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Phenyl azo dye (generic). 721.5917... Substances § 721.5917 Phenyl azo dye (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a phenyl azo dye (PMN P-02-17) is subject to...

  1. 40 CFR 721.988 - Pyrazolone azomethine dye (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Pyrazolone azomethine dye (generic... Substances § 721.988 Pyrazolone azomethine dye (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a pyrazolone azomethine dye...

  2. Biotreatment of anthraquinone dye Drimarene Blue K 2 RL | Siddiqui ...

    African Journals Online (AJOL)

    Drimarene Blue (Db) K2RL is a reactive anthraquinone dye, used extensively in textile industry, due to poor adsorbability to textile fiber; it has a higher exhaustion rate in wastewater. The dye is toxic, carcinogenic, mutagenic and resistant to degradation. Decolorization of this dye was studied in two different systems.

  3. Aerobic decolourization of two reactive azo dyes under varying ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-02-01

    Feb 1, 2010 ... Key words: Bioremediation, decolourization, textile dye, Bacillus cereus. INTRODUCTION. Dyes are organic chemical compounds, which impart colour to other materials by saturating them in aqueous solution. Synthetic dyes have a wide application in the food, pharmaceutical, textile, leather, cosmetics ...

  4. Taming fluorescence yield of dye insensitive to temperature by non ...

    Indian Academy of Sciences (India)

    2014-02-12

    Feb 12, 2014 ... ... due to the heat generated by circulation pumps and non-radiative decay processes of excited dye molecules. The QYF of RhB dye in water was found to be not sensitive to temperature in the practical operating region 16–25°C of dye laser by adopting supramolecular route to form an inclusion complex of ...

  5. 17 EFFECTS OF MORDANTING METHODS OF DYE FROM ...

    African Journals Online (AJOL)

    Frederick Iraki

    dyeing woven cotton with natural dyes from the leaves of Vernonia amygdalina. The effects analyzed are color fastness ... INTRODUCTION. In Uganda, plants have traditionally been utilized as a source of colorants for dyeing mats, ropes and other home based materials for a long time. These plants are a potential source of ...

  6. Decolourisation of chemically different dyes by enzymes from spent ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-01-04

    Jan 4, 2010 ... 042 Afr. J. Biotechnol. microorganisms degrade dyes by azoreductase activity and this leads to the formation of aromatic amines which pose a more serious biotoxic threat than the original azo dyes (Chung and Stevens, 1993). The biodegradation of dyes by white rot fungi and their ligninolytic enzyme sys-.

  7. 21 CFR 864.1850 - Dye and chemical solution stains.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Dye and chemical solution stains. 864.1850 Section... solution stains. (a) Identification. Dye and chemical solution stains for medical purposes are mixtures of synthetic or natural dyes or nondye chemicals in solutions used in staining cells and tissues for diagnostic...

  8. Sequestration of Congo red Dye from Aqueous Solution using ...

    African Journals Online (AJOL)

    The adsorption of Congo red dye in aqueous solution using locally sourced almond shell adsorbent was investigated in this study. The effect of various factors such as contact time, initial dye concentration and adsorbent dosage on the adsorption capacity of the adsorbent was studied. The adsorption of Congo red dye was ...

  9. Controlled Modulation of Serum Protein Binding and Biodistribution of Asymmetric Cyanine Dyes by Variation of the Number of Sulfonate Groups

    Directory of Open Access Journals (Sweden)

    Franziska M. Hamann

    2011-07-01

    Full Text Available To assess the suitability of asymmetric cyanine dyes for in vivo fluoro-optical molecular imaging, a comprehensive study on the influence of the number of negatively charged sulfonate groups governing the hydrophilicity of the DY-67x family of asymmetric cyanines was performed. Special attention was devoted to the plasma protein binding capacity and related pharmacokinetic properties. Four members of the DY-67x cyanine family composed of the same main chromophore, but substituted with a sequentially increasing number of sulfonate groups (n = 1−4; DY-675, DY-676, DY-677, DY-678, respectively, were incubated with plasma proteins dissolved in phosphate-buffered saline. Protein binding was assessed by absorption spectroscopy, gel electrophoresis, ultrafiltration, and dialysis. Distribution of dye in organs was studied by intraveneous injection of 62 nmol dye/kg body weight into mice (n = 12; up to 180 minutes postinjection using whole-body near-infrared fluorescence imaging. Spectroscopic studies, gel electrophoresis, and dialysis demonstrated reduced protein binding with increasing number of sulfonate groups. The bovine serum albumin binding constant of the most hydrophobic dye, DY-675, is 18 times higher than that of the most hydrophilic fluorophore, DY-678. In vivo biodistribution analysis underlined a considerable influence of dye hydrophilicity on biodistribution and excretion pathways, with the more hydrophobic dyes, DY-675 and DY-676, accumulating in the liver, followed by strong fluorescence signals in bile and gut owing to accumulation in feces and comparatively hydrophilic DY-678-COOH accumulating in the bladder. Our results demonstrate the possibility of selectively controlling dye-protein interactions and, thus, biodistribution and excretion pathways via proper choice of the fluorophore's substitution pattern. This underlines the importance of structure-property relationships for fluorescent labels. Moreover, our data could provide the

  10. Using two dyes with the same fluorophore to monitor cellular calcium concentration in an extended range.

    Directory of Open Access Journals (Sweden)

    Lourdes Figueroa

    Full Text Available We extend the sensitivity of quantitative concentration imaging to an approximately 1000-fold range of concentrations by a method that uses two fluorescent dyes with the same fluorophore, having different affinity for the monitored species. While the formulation and illustration refer to a monitor of calcium concentration, the method is applicable to any species that binds to multiple indicators with the same spectral properties. The use of a common fluorophore has the virtue of leaving vast regions of the electromagnetic spectrum available for other applications. We provide the exact analytic expression relating measured fluorescence to [Ca(2+] at equilibrium and an approximate analytic expression that does not require the equilibrium assumption. The sensitivity of the method is calculated numerically for two useful dye pairs. As illustrative application of the enhanced measurement, we use fluo-4 and fluo-4FF to image the calcium wave produced by a cardiac myocyte in response to a small artificial calcium spark.

  11. The dopant dependent photocatalytic activity of polyaniline towards the degradation of Rose Bengal dye

    Science.gov (United States)

    Chatterjee, Mukulika Jana; Banerjee, Dipali; Ghosh, Amrita; Mondal, Anup

    2016-05-01

    Polyaniline (PANI) with two different dopants, hydrochloric acid (HCl) and bismuth nitrate (Bi (NO3)3), were synthesized to investigate the effect of dopant on photocatalytic degradation of Rose Bengal, an organic dye, in presence of sunlight. PANI, synthesized by in situ polymerization was characterized by FESEM images, FTIR and UV-Vis spectra. FESEM images show rod like structures obtained for both the dopants. FTIR spectra confirms the formation of conducting PANI with the presence of C=N, C=C stretching modes in quinoid and benzenoid units. Band gap of PANI has been obtained from UV-Vis spectrum. Doped polyaniline exhibited a fast degradation of dye by 98.62 % & 98.12 % within 5 min & 8 min under visible light illumination for the dopant HCl & Bi (NO3)3 respectively.

  12. Two dye combinations suitable for two-color/two-dye laser-induced fluorescence thermography for ethanol

    Science.gov (United States)

    Fenner, Andreas; Stephan, Peter

    2017-06-01

    This paper presents two dye combinations suitable for two-color/two-dye laser-induced fluorescence thermography for ethanol. Besides the temperature dependency of the fluorescence, the influences of laser fluence, dye concentration, pressure, dissolved air, and photobleaching are also discussed. The experimental data are compared with models and data available in literature. Based on this, parameter ranges for two-color/two-dye laser-induced fluorescence thermography applications can be determined.

  13. Tracking of a Fluorescent Dye in a Freshwater Lake with an Unmanned Surface Vehicle and an Unmanned Aircraft System

    Directory of Open Access Journals (Sweden)

    Craig Powers

    2018-01-01

    Full Text Available Recent catastrophic events in our oceans, including the spill of toxic oil from the explosion of the Deepwater Horizon drilling rig and the rapid dispersion of radioactive particulates from the meltdown of the Fukushima Daiichi nuclear plant, underscore the need for new tools and technologies to rapidly respond to hazardous agents. Our understanding of the movement and aerosolization of hazardous agents from natural aquatic systems can be expanded upon and used in prevention and tracking. New technologies with coordinated unmanned robotic systems could lead to faster identification and mitigation of hazardous agents in lakes, rivers, and oceans. In this study, we released a fluorescent dye (fluorescein into a freshwater lake from an anchored floating platform. A fluorometer (fluorescence sensor was mounted underneath an unmanned surface vehicle (USV, unmanned boat and was used to detect and track the released dye in situ in real-time. An unmanned aircraft system (UAS was used to visualize the dye and direct the USV to sample different areas of the dye plume. Image processing tools were used to map concentration profiles of the dye plume from aerial images acquired from the UAS, and these were associated with concentration measurements collected from the sensors onboard the USV. The results of this project have the potential to transform monitoring strategies for hazardous agents, enabling timely and accurate exposure assessment and response in affected areas. Fast response is essential in reacting to the introduction of hazardous agents, in order to quickly predict and contain their spread.

  14. Emulsion liquid membrane for textile dye removal: Stability study

    Science.gov (United States)

    Kusumastuti, Adhi; Syamwil, Rodia; Anis, Samsudin

    2017-03-01

    Although textile dyes is basically available in very low concentration; it should be removed due to the toxicity to human body and environment. Among the existing methods, emulsion liquid membrane (ELM) is a promising method by providing high interfacial area and the ability to remove a very low concentration of the solute. The optimal emulsions were produced using commercially supplied homogeniser. The drop size was measured by the aid of microscope and image J software. Initially, methylene blue in simulated wastewater was extracted using a stirrer. Methylene blue concentration was determined using spectrophotometer. The research obtained optimal emulsion at surfactant concentration of 4 wt. %, kerosene as diluent, emulsification time of 30 min, emulsification speed of 2000 rpm. The lowest membrane breakage and the longest stability time were about 0.11% and 150 min, respectively.

  15. A near-infrared phthalocyanine dye-labeled agent for integrin αvβ6-targeted theranostics of pancreatic cancer.

    Science.gov (United States)

    Gao, Duo; Gao, Liquan; Zhang, Chenran; Liu, Hao; Jia, Bing; Zhu, Zhaohui; Wang, Fan; Liu, Zhaofei

    2015-06-01

    Integrin αvβ6 is widely upregulated in variant malignant cancers but is undetectable in normal organs, making it a promising target for cancer diagnostic imaging and therapy. Using streptavidin-biotin chemistry, we synthesized an integrin αvβ6-targeted near-infrared phthalocyanine dye-labeled agent, termed Dye-SA-B-HK, and investigated whether it could be used for cancer imaging, optical imaging-guided surgery, and phototherapy in pancreatic cancer mouse models. Dye-SA-B-HK specifically bound to integrin αvβ6 in vitro and in vivo with high receptor binding affinity. Using small-animal optical imaging, we detected subcutaneous and orthotopic BxPC-3 human pancreatic cancer xenografts in vivo. Upon optical image-guidance, the orthotopically growing pancreatic cancer lesions could be successfully removed by surgery. Using light irradiation, Dye-SA-B-HK manifested remarkable antitumor effects both in vitro and in vivo. (18)F-FDG positron emission tomography (PET) imaging and ex vivo fluorescence staining validated the observed decrease in proliferation of treated tumors by Dye-DA-B-HK phototherapy. Tissue microarray results revealed overexpression of integrin αvβ6 in over 95% cases of human pancreatic cancer, indicating that theranostic application of Dye-DA-B-HK has clear translational potential. Overall, the results of this study demonstrated that integrin αvβ6-specific Dye-SA-B-HK is a promising theranostic agent for the management of pancreatic cancer. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Dye-sensitized solar cells with natural dyes extracted from achiote seeds

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Ortiz, N.M.; Vazquez-Maldonado, I.A.; Azamar-Barrios, J.A.; Oskam, G. [Departamento de Fisica Aplicada, CINVESTAV-IPN, Merida, Yuc. 97310 (Mexico); Perez-Espadas, A.R.; Mena-Rejon, G.J. [Laboratorio de Quimica Organica de Investigacion, Facultad de Quimica, Universidad Autonoma de Yucatan, Merida, Yuc. 97150 (Mexico)

    2010-01-15

    We have explored the application of natural dyes extracted from the seeds of the achiote shrub (Bixa orellana L.) in dye-sensitized solar cells (DSCs). The main pigments are bixin and norbixin, which were obtained by separation and purification from the dark-red extract (annatto). The dyes were characterized using {sup 1}H-NMR, FTIR spectroscopy, and UV-Vis spectrophotometry. Solar cells were prepared using TiO{sub 2} and ZnO nanostructured, mesoporous films and the annatto, bixin, and norbixin as sensitizers. The best results were obtained with bixin-sensitized TiO{sub 2} solar cells with efficiencies of up to 0.53%, illustrating the importance of purification of dyes from natural extracts. (author)

  17. Dye-Sensitized Solar Cells (DSSCs) reengineering using TiO2 with natural dye (anthocyanin)

    Science.gov (United States)

    Subodro, Rohmat; Kristiawan, Budi; Ramelan, Ari Handono; Wahyuningsih, Sayekti; Munawaroh, Hanik; Hanif, Qonita Awliya; Saputri, Liya Nikmatul Maula Zulfa

    2017-01-01

    This research on Dye-Sensitized Solar Cells (DSSCs) reengineering was carried out using TiO2 with natural dye (anthocyanin). The fabrication of active carbon layer/TiO2 DSSC solar cell was based on natural dye containing anthocyanins such as mangosteen peel, red rose flower, black glutinous rice, and purple eggplant peel. DSSC was prepared with TiO2 thin layer doped with active carbon; Natural dye was analyzed using UV-Vis and TiO2 was analyzed using X-ray diffractometer (XRD), meanwhile scanning electron microscope (SEM) was used to obtain the size of the crystal. Keithley instrument test was carried out to find out I-V characteristics indicating that the highest efficiency occurred in DSSCs solar cell with 24-hour soaking with mangosteen peel 0.00047%.

  18. Dye linked conjugated homopolymers: using conjugated polymer electroluminescence to optically pump porphyrin-dye emission

    DEFF Research Database (Denmark)

    Nielsen, K.T.; Spanggaard, H.; Krebs, Frederik C

    2004-01-01

    Zinc-porphyrin dye molecules were incorporated into the backbone of a conjugated polymer material by a method, which allowed for the incorporation of only one zinc-porphyrin dye molecule into the backbone of each conjugated polymer molecule. The electronic properties of the homopolymer were....... Electroluminescent devices of the homopolymer itself and of the zinc-porphyrin containing polymer were prepared and the nature of the electroluminescence was characterized. The homopolymer segments were found to optically pump the emission of the zinc-porphyrin dye moities. The homopolymer exhibits blue......-green emission and the zinc-porphyrin linked homopolymers emit near-infrared/infrared light. This was demonstrated to be due to electroluminescence pumping of the zinc-porphyrin moieties that were covalently linked to homopolymer material. When only one zinc-porphyrin dye was incorporated into the backbone...

  19. Development auxiliaries for dyeing polyester with disperse dyes at low temperatures

    Science.gov (United States)

    Carrion-Fite, F. J.; Radei, S.

    2017-10-01

    High-molecular weight organic compounds known as carriers are widely used to expedite polyester dyeing at atmospheric pressure at 100 °C. However, carriers are usually poorly biodegradable and can partially plasticize fibres. Also, dyeing at temperatures above 100 °C in the absence of a carrier entails using expensive equipment. In this work, we developed an alternative method for dyeing polyester at temperatures below 100 °C that reduces energy expenses, dispenses with the need to invest in new equipment and avoids the undesirable effects of non-biodegradable carriers. The method uses disperse dyes in a microemulsion containing a low proportion of a non-toxic organic solvent and either of two alternative development auxiliaries (coumarin and o-vanillin) that is prepared with the aid of ultrasound.

  20. Dye-sensitized photopolymerization of N, N ...

    Indian Academy of Sciences (India)

    The rate of polymerization is proportional to [MBA] and [AH2]. Kinetic results indicate that semi-quinone (DH) dye radical and semi-oxidized form () of ascorbic acid are unable to initiate polymerization. Formation of H2O2 is proposed and confirmed. A suitable mechanism is proposed in accordance with experimental ...

  1. Dye-sensitised solar cell (artificial photosynthesis)

    CSIR Research Space (South Africa)

    Le Roux, Lukas J

    2006-02-01

    Full Text Available is the nano- crystalline TiO2dye- sensitised solar cell (DSC), in conjunction with several new concepts, such as nanotechnology and molecular devices. An efficient and low-cost cell can be produced by using simple materials. The production process generates...

  2. SOLID STATE PHOTOELECTROCHEMICAL CELL BASED ON DYE ...

    African Journals Online (AJOL)

    isothiocyanato)bis(2,2'-bipyridyl-4,4'-dicarboxylato)-ruthenium(II) (N719) dye has been constructed and characterized. The current density–voltage characteristics in the dark and under white light illumination and action spectra under monochromatic ...

  3. COLOR POLLUTION CONTROL IN TEXTILE DYEING INDUSTRY ...

    African Journals Online (AJOL)

    a

    E-mail: ssreedharreddy@yahoo.com. COLOR POLLUTION CONTROL IN TEXTILE DYEING INDUSTRY EFFLUENTS. USING TANNERY SLUDGE DERIVED ACTIVATED CARBON. Sajjala Sreedhar Reddy1∗, Bijjam Kotaiah2 and Nanaga Siva Prasad Reddy3. 1Adama University, Faculty of Technology, Post Box No. 1888 ...

  4. Micro-Cavity Fluidic Dye Laser

    DEFF Research Database (Denmark)

    Helbo, Bjarne; Kristensen, Anders; Menon, Aric Kumaran

    2003-01-01

    We have successfully designed, fabricated and characterized a micro-cavity fluidic dye laser with metallic mirrors, which can be integrated with polymer based lab-on-a-chip microsystems without further processing steps. A simple rate-equation model is used to predict the average pumping power...

  5. Removal of Triphenylmethane Dyes by Bacterial Consortium

    Directory of Open Access Journals (Sweden)

    Jihane Cheriaa

    2012-01-01

    Full Text Available A new consortium of four bacterial isolates (Agrobacterium radiobacter; Bacillus spp.; Sphingomonas paucimobilis, and Aeromonas hydrophila-(CM-4 was used to degrade and to decolorize triphenylmethane dyes. All bacteria were isolated from activated sludge extracted from a wastewater treatment station of a dyeing industry plant. Individual bacterial isolates exhibited a remarkable color-removal capability against crystal violet (50 mg/L and malachite green (50 mg/L dyes within 24 h. Interestingly, the microbial consortium CM-4 shows a high decolorizing percentage for crystal violet and malachite green, respectively, 91% and 99% within 2 h. The rate of chemical oxygen demand (COD removal increases after 24 h, reaching 61.5% and 84.2% for crystal violet and malachite green, respectively. UV-Visible absorption spectra, FTIR analysis and the inspection of bacterial cells growth indicated that color removal by the CM-4 was due to biodegradation. Evaluation of mutagenicity by using Salmonella typhimurium test strains, TA98 and TA100 studies revealed that the degradation of crystal violet and malachite green by CM-4 did not lead to mutagenic products. Altogether, these results demonstrated the usefulness of the bacterial consortium in the treatment of the textile dyes.

  6. (Hair-dye) and Renal Impairment

    African Journals Online (AJOL)

    Introduction: Paraphenylenediamine (PPD) is widely used in hair dyes and cosmetic skin application. PPD intoxication following oral ingestion could be an important cause of ARF in Sudan, Morocco and the Indian Subcontinent. Repeated and prolonged exposure to PPD may also be associated with Chronic Kidney ...

  7. Removal of Triphenylmethane Dyes by Bacterial Consortium

    Science.gov (United States)

    Cheriaa, Jihane; Khaireddine, Monia; Rouabhia, Mahmoud; Bakhrouf, Amina

    2012-01-01

    A new consortium of four bacterial isolates (Agrobacterium radiobacter; Bacillus spp.; Sphingomonas paucimobilis, and Aeromonas hydrophila)-(CM-4) was used to degrade and to decolorize triphenylmethane dyes. All bacteria were isolated from activated sludge extracted from a wastewater treatment station of a dyeing industry plant. Individual bacterial isolates exhibited a remarkable color-removal capability against crystal violet (50 mg/L) and malachite green (50 mg/L) dyes within 24 h. Interestingly, the microbial consortium CM-4 shows a high decolorizing percentage for crystal violet and malachite green, respectively, 91% and 99% within 2 h. The rate of chemical oxygen demand (COD) removal increases after 24 h, reaching 61.5% and 84.2% for crystal violet and malachite green, respectively. UV-Visible absorption spectra, FTIR analysis and the inspection of bacterial cells growth indicated that color removal by the CM-4 was due to biodegradation. Evaluation of mutagenicity by using Salmonella typhimurium test strains, TA98 and TA100 studies revealed that the degradation of crystal violet and malachite green by CM-4 did not lead to mutagenic products. Altogether, these results demonstrated the usefulness of the bacterial consortium in the treatment of the textile dyes. PMID:22623907

  8. Energy consumption in a dye works

    Energy Technology Data Exchange (ETDEWEB)

    Aird, R.J.; Bruffell, P.D.; Wooldridge, D.M.

    1984-06-01

    Basic engineering principles were used to estimate the energy consumption in specific areas of a small dye works. This energy was related to production and heating requirements and this was found to correspond with historical data. The reduction in fuel consumption due to insulation of the steam supply was predicted and the achieved saving was clearly demonstrated using a cumulative sum chart.

  9. Triphenylmethane Dye Activation of Beta-Arrestin

    Science.gov (United States)

    2013-01-01

    β-Arrestins regulate G protein-coupled receptor signaling as competitive inhibitors and protein adaptors. Low molecular weight biased ligands that bind receptors and discriminate between the G protein dependent arm and β-arrestin, clathrin-associated arm of receptor signaling are considered therapeutically valuable as a result of this distinctive pharmacological behavior. Other than receptor agonists, compounds that activate β-arrestins are not available. We show that within minutes of exposure to the cationic triphenylmethane dyes malachite green and brilliant green, tissue culture cells recruit β-arrestins to clathrin scaffolds in a receptor-activation independent manner. In the presence of these compounds, G protein signaling is inhibited, ERK and GSK3β signaling are preserved, and the recruitment of the beta2-adaptin, AP2 adaptor complex to clathrin as well as transferrin internalization is reduced. Moreover, malachite green binds β-arrestin2-GFP coated immunotrap beads relative to GFP only coated beads. Triphenylmethane dyes are FDA approved for topical use on newborns as components of triple-dye preparations and are not approved but used effectively as aqueous antibiotics in fish husbandry. As possible carcinogens, their chronic ingestion in food preparations, particularly through farmed fish, is discouraged in the U.S. and Europe. Our results indicate triphenylmethane dyes as a result of novel pharmacology may have additional roles as β-arrestin/clathrin pathway signaling modulators in both pharmacology research and clinical therapy. PMID:23865508

  10. Optofluidic dye laser in a foil

    DEFF Research Database (Denmark)

    Vannahme, Christoph; Christiansen, Mads Brøkner; Mappes, Timo

    2010-01-01

    First order distributed feedback optofluidic dye lasers embedded in a 350 mu m thick TOPAS (R) foil are demonstrated. They are designed in order to give high output pulse energies. Microfluidic channels and first order distributed feedback gratings are fabricated in parallel by thermal nanoimprint...

  11. Dye-sensitised solar cell (artificial photosynthesis)

    CSIR Research Space (South Africa)

    Le Roux, Lukas J

    2005-07-01

    Full Text Available A novel system that harnesses solar energy is the nano-crystalline TiO dye-sensitised solar cell (DSC), in conjunction with several new concepts, such as nanotechnology and molecular devices. An efficient and low-cost cell can be produced by using...

  12. Expeditious, mechanochemical synthesis of BODIPY dyes

    OpenAIRE

    Laramie P. Jameson; Sergei V. Dzyuba

    2013-01-01

    Summary BODIPY dyes have been synthesized under solvent-free or essentially solvent-free conditions, within about 5 minutes in an open-to-air setup by using a pestle and mortar, with yields that are comparable to those obtained via traditional routes that typically require reaction times of several hours to days.

  13. Expeditious, mechanochemical synthesis of BODIPY dyes

    Directory of Open Access Journals (Sweden)

    Laramie P. Jameson

    2013-04-01

    Full Text Available BODIPY dyes have been synthesized under solvent-free or essentially solvent-free conditions, within about 5 minutes in an open-to-air setup by using a pestle and mortar, with yields that are comparable to those obtained via traditional routes that typically require reaction times of several hours to days.

  14. Expeditious, mechanochemical synthesis of BODIPY dyes.

    Science.gov (United States)

    Jameson, Laramie P; Dzyuba, Sergei V

    2013-01-01

    BODIPY dyes have been synthesized under solvent-free or essentially solvent-free conditions, within about 5 minutes in an open-to-air setup by using a pestle and mortar, with yields that are comparable to those obtained via traditional routes that typically require reaction times of several hours to days.

  15. Effect of dye extracting solvents and sensitization time on photovoltaic performance of natural dye sensitized solar cells

    Directory of Open Access Journals (Sweden)

    Md. Khalid Hossain

    Full Text Available In this study, natural dye sensitizer based solar cells were successfully fabricated and photovoltaic performance was measured. Sensitizer (turmeric sources, dye extraction process, and photoanode sensitization time of the fabricated cells were analyzed and optimized. Dry turmeric, verdant turmeric, and powder turmeric were used as dye sources. Five distinct types of solvents were used for extraction of natural dye from turmeric. Dyes were characterized by UV–Vis spectrophotometric analysis. The extracted turmeric dye was used as a sensitizer in the dye sensitized solar cell’s (DSSC photoanode assembly. Nano-crystalline TiO2 was used as a film coating semiconductor material of the photoanode. TiO2 films on ITO glass substrate were prepared by simple doctor blade technique. The influence of the different parameters VOC, JSC, power density, FF, and η% on the photovoltaic characteristics of DSSCs was analyzed. The best energy conversion performance was obtained for 2 h adsorption time of dye on TiO2 nano-porous surface with ethanol extracted dye from dry turmeric. Keywords: DSSC, Natural dye, TiO2 photoanode, Dye extracting solvent, Dye-adsorption time

  16. Dye-sensitized solar cell using natural dyes extracted from spinach and ipomoea

    Energy Technology Data Exchange (ETDEWEB)

    Chang, H., E-mail: f10381@ntut.edu.t [Department of Mechanical Engineering, National Taipei University of Technology, No. 1. Sec. 3, Chung-Hsiao E. Rd., Taipei 10608, Taiwan (China); Wu, H.M. [Department of Materials Engineering, Tatung University, No. 40, Sec. 3, Jhongshan N. Rd. Jhongshan District, Taipei City 104, Taiwan (China); Chen, T.L. [Department of Industrial Design, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd., Taipei 10608, Taiwan (China); Huang, K.D. [Department of Vehicle Engineering, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd., Taipei 10608, Taiwan (China); Jwo, C.S. [Department of Energy and Air-Conditioning Refrigeration Engineering, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd., Taipei 10608, Taiwan (China); Lo, Y.J. [Department of Mechanical Engineering, National Taipei University of Technology, No. 1. Sec. 3, Chung-Hsiao E. Rd., Taipei 10608, Taiwan (China)

    2010-04-16

    This study used spinach extract, ipomoea leaf extract and their mixed extracts as the natural dyes for a dye-sensitized solar cell (DSSC). Spinach and ipomoea leaves were first placed separately in ethanol and the chlorophyll of these two kinds of plants was extracted to serve as the natural dyes for using in DSSCs. In addition, the self-developed nanofluid synthesis system prepared a TiO{sub 2} nanofluid with an average particle size of 50 nm. Electrophoresis deposition was performed to let the TiO{sub 2} deposit nanoparticles on the indium tin oxide (ITO) conductive glass, forming a TiO{sub 2} thin film with the thickness of 11.61 {mu}m. This TiO{sub 2} thin film underwent sintering at 450 {sup o}C to enhance the compactness of thin film. Finally, the sintered TiO{sub 2} thin film was immersed in the natural dye solutions extracted from spinach and ipomoea leaves, completing the production of the anode of DSSC. This study then further inspected the fill factor, photoelectric conversion efficiency and incident photon current efficiency of the encapsulated DSSC. According to the experimental results of current-voltage curve, the photoelectric conversion efficiency of the DSSCs prepared by natural dyes from ipomoea leaf extract is 0.318% under extraction temperature of 50 {sup o}C and pH value of extraction fluid at 1.0. This paper also investigated the influence of the temperature in the extraction process of this kind of natural dye and the influence of pH value of the dye solution on the UV-VIS patterns absorption spectra of the prepared natural dye solutions, and the influence of these two factors on the photoelectric conversion efficiency of DSSC.

  17. Pond dyes are Culex mosquito oviposition attractants

    Directory of Open Access Journals (Sweden)

    Natali Ortiz Perea

    2017-05-01

    Full Text Available Background British mosquito population distribution, abundance, species composition and potential for mosquito disease transmission are intimately linked to the physical environment. The presence of ponds and water storage can significantly increase the density of particular mosquito species in the garden. Culex pipiens is the mosquito most commonly found in UK gardens and a potential vector of West Nile Virus WNV, although the current risk of transmission is low. However any factors that significantly change the distribution and population of C. pipiens are likely to impact subsequent risk of disease transmission. Pond dyes are used to control algal growth and improve aesthetics of still water reflecting surrounding planting. However, it is well documented that females of some species of mosquito prefer to lay eggs in dark water and/or containers of different colours and we predict that dyed ponds will be attractive to Culex mosquitoes. Methods Black pond dye was used in oviposition choice tests using wild-caught gravid C. pipiens. Larvae from wild-caught C. pipiens were also reared in the pond dye to determine whether it had any impact on survival. An emergence trap caught any adults that emerged from the water. Water butts (80 L were positioned around university glasshouses and woodland and treated with black pond dye or left undyed. Weekly sampling over a six month period through summer and autumn was performed to quantified numbers of larvae and pupae in each treatment and habitat. Results Gravid female Culex mosquitoes preferred to lay eggs in dyed water. This was highly significant in tests conducted under laboratory conditions and in a semi-field choice test. Despite this, survivorship in black dyed water was significantly reduced compared to undyed water. Seasonal analysis of wild larval and pupal numbers in two habitats with and without dye showed no impact of dye but a significant impact of season and habitat. Mosquitoes were more

  18. Method of dye removal for the textile industry

    Science.gov (United States)

    Stone, Mark L.

    2000-01-01

    The invention comprises a method of processing a waste stream containing dyes, such as a dye bath used in the textile industry. The invention comprises using an inorganic-based polymer, such as polyphosphazene, to separate dyes and/or other chemicals from the waste stream. Membranes comprising polyphosphazene have the chemical and thermal stability to survive the harsh, high temperature environment of dye waste streams, and have been shown to completely separate dyes from the waste stream. Several polyphosplhazene membranes having a variety of organic substituent have been shown effective in removing color from waste streams.

  19. Study on decolorization of dyeing wastewater by electrochemical treatment

    Science.gov (United States)

    Chen, Jianjun; Xiaohui, Wang; Hao, Wu; Qi, Jiang

    2018-02-01

    In view of the decolorization of dyeing wastewater, three different kinds of simulated dyeing wastewater were treated by electrochemical method. The effects of current density, initial pH, electrolyte concentration and initial concentration of dye on the treatment effect were investigated, and the decolorization mechanism and color reversion were studied. The experimental results show that the decolorization rate of the three kinds of dyeing wastewater is more than 90% after 60min treatment. And the decolorization process is mainly chromogenic groups gradually destroyed, the dye molecules are gradually degraded. Moreover, in the natural conditions, aeration conditions, heating conditions, almost no phenomenon of color reversion occured.

  20. Re-evaluation of azo dyes as food additives

    DEFF Research Database (Denmark)

    Pratt, Iona; Larsen, John Christian; Mortensen, Alicja

    2013-01-01

    Aryl azo compounds are widely used as colorants (azo dyes) in a wide range of products including textiles, leather, paper, cosmetics, pharmaceuticals and food.As part of its systematic re-evaluation of food additives, the European Food Safety Authority (EFSA) has carried out new risk assessments...... of allazo dyes permitted in food. EFSA has also evaluated a number of azo dyes found illegally in food in recent years, including Sudan dyes, Para Red and Orange II. The re-evaluation of all food colours, including the azo dyes,was considered high priority (i) because colorants were among the first...

  1. Encapsulation of Solitary Dye Molecules in Silica Nanoshells

    Science.gov (United States)

    Levinger, Nancy E.; Langdon, Benjamin

    2000-03-01

    We report on the encapsulation of solitary coumarin 343 dye molecules within hollow silica nanospheres. Through steady-state and time-resolved spectroscopy, we demonstrate that the dye molecule is isolated from bulk solution. The fluorescence lifetime of the dye is dramatically shortened and non-single exponential. Fluorescence quenching shows that the encapsulated dye is unaffected by the presence of the methyl viologen quencher. Time resolved fluorescence anisotropy shows that the encapsulated dye does not move freely as it does in bulk solution. Interpretation of the results will be presented.

  2. Raman Spectroscopic Investigation of Dyes in Spices

    Science.gov (United States)

    Uhlemann, Ute; Ramoji, Anuradha; Rösch, Petra; Da Costa Filho, Paulo Augusto; Robert, Fabien; Popp, Jürgen

    2010-08-01

    In this study, a number of synthetic colorants for spices have been investigated by means of Raman spectroscopy, resonance Raman spectroscopy, and surface enhanced (resonance) Raman spectroscopy (SER(S)). The aim of the study was the determination of limits of detection for each dye separately and in binary mixtures of dyes in spiked samples of the spices. Most of the investigated dyes have been azo dyes, some being water-soluble, the other being fat-soluble. Investigating the composition of food preparations is an ongoing and important branch of analytical sciences. On one hand, new ingredients have to be analyzed with regard to their contents, on the other hand, raw materials that have been tampered have to be eliminated from food production processes. In the last decades, the various Raman spectroscopic methods have proven to be successful in many areas of life and materials sciences. The ability of Raman spectroscopy to distinguish even structural very similar analytes by means of their vibrational fingerprint will also be important in this study. Nevertheless, Raman scattering is a very weak process that is oftentimes overlaid by matrix interferences or fluorescence. In order to achieve limits of detection in the nanomolar range, the signal intensity has to be increased. According to the well-known equations, there are several ways of achieving this increase: •increasing sample concentration •increasing laser power •decreasing the laser wavelength •using electronic resonance •increasing the local electromagnetic field In this study, nearly all of the above-mentioned principles were applied. In a first step, all dyes were investigated in solution at different concentrations to determine a limit of detection. In the second step, spiked spice samples have been extracted with a variety of solvents and process parameters tested. To lower the limit of detection even further, SERS spectroscopy has been used as well in as out of electronic resonance.

  3. BODIPY-doped silica nanoparticles with reduced dye leakage and enhanced singlet oxygen generation.

    Science.gov (United States)

    Wang, Zhuyuan; Hong, Xuehua; Zong, Shenfei; Tang, Changquan; Cui, Yiping; Zheng, Qingdong

    2015-07-27

    Photodynamic therapy (PDT) is a promising modality for cancer treatment. The essential element in PDT is the photosensitizer, which can be excited by light of a specific wavelength to generate cytotoxic oxygen species (ROS) capable of killing tumor cells. The effectiveness of PDT is limited in part by the low yield of ROS from existing photosensitizers and the unwanted side effects induced by the photosensitizers toward normal cells. Thus the design of nanoplatforms with enhanced PDT is highly desirable but remains challenging. Here, we developed a heavy atom (I) containing dipyrromethene boron difluoride (BODIPY) dye with a silylated functional group, which can be covalently incorporated into a silica matrix to form dye-doped nanoparticles. The incorporated heavy atoms can enhance the generation efficiency of ROS. Meanwhile, the covalently dye-encapsulated nanoparticles can significantly reduce dye leakage and subsequently reduce unwanted side effects. The nanoparticles were successfully taken up by various tumor cells and showed salient phototoxicity against these cells upon light irradiation, demonstrating promising applications in PDT. Moreover, the incorporated iodine atom can be replaced by a radiolabeled iodine atom (e.g., I-124, I-125). The resulting nanoparticles will be good contrast agents for positron emission tomography (PET) imaging with their PDT functionality retained.

  4. pH-sensitive wax emulsion copolymerization with acrylamide hydrogel using gamma irradiation for dye removal

    Science.gov (United States)

    Ghobashy, Mohamed Mohamady; Elhady, Mohamed., A.

    2017-05-01

    Emulsion polymerization is an efficient method for the production of new wax-hydrogel matrices of cetyl alcohol: stearic acid wax and acrylamide hydrogel using triethylamine (TEA) as an emulsifier. A cross-linking reaction occurred when a mixture of wax-hydrogel solution was irradiated with gamma rays at a dose of 20 kGy. The gelation percentage of the matrices (CtOH-StA/PAAm) was 86%, which indicates that a sufficiently high conversion occurred in these new wax-hydrogel matrices. The ability of PAAm and CtOH-StA/PAAm as an adsorbent for dye removal was investigated. The removal of three reactive dyes, namely Remazol Red (RR), Amido Black (AB), and Toluidine Blue (TB), from aqueous solutions depends on the pH of the dye solution. Removal efficiency was investigated by UV spectrophotometry, and the results showed the affinity of the wax hydrogel to adsorb TB was 98% after 320 min. Fourier transform infrared-attenuated total reflectance spectra confirmed the cross-linking process involved between the chains of wax and hydrogel; furthermore, scanning electron microscopy images showed that the wax and hydrogel were completely miscible to form a single matrix. Swelling measurements showed the high affinity of adsorbed dyes from aqueous solutions at different pH values to the wax-hydrogel network; the highest swelling values of 13.05 and 8.24 (g/g) were observed at pH 10 and 6, respectively

  5. Synthesis of oxidized guar gum by dry method and its application in reactive dye printing.

    Science.gov (United States)

    Gong, Honghong; Liu, Mingzhu; Zhang, Bing; Cui, Dapeng; Gao, Chunmei; Ni, Boli; Chen, Jiucun

    2011-12-01

    The aim of this study was to prepare oxidized guar gum with a simple dry method, basing on guar gum, hydrogen peroxide and a small amount of solvent. To obtain a product with suitable viscosity for reactive dye printing, the effects of various factors such as the amount of oxidant and solvent, reaction temperature and time were studied with respect to the viscosity of reaction products. The product was characterized by Fourier transform infrared spectroscopy, size exclusion chromatography, scanning electron microscopy and differential scanning calorimetry. The hydrated rate of guar gum and oxidized guar gum was estimated through measuring the required time when their solutions (1%, w/v) reached the maximum viscosity. The effects of the salt concentration and pH on viscosity of the resultant product were studied. The mixed paste containing oxidized guar gum and carboxymethyl starch was prepared and its viscosity was determined by the viscometer. The rheological property of the mixed paste was appraised by the printing viscosity index. In addition, the applied effect of mixed paste in reactive dye printing was examined by assessing the fabric stiffness, color yield and sharp edge to the printed image in comparison with sodium alginate. And the results indicated that the mixed paste could partially replace sodium alginate as thickener in reactive dye printing. The study also showed that the method was low cost and eco-friendly and the product would have an extensive application in reactive dye printing. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Improving the Spectral Response of Black Dye by Cosensitization with a Simple Indoline Based Dye in Dye-Sensitized Solar Cell

    Directory of Open Access Journals (Sweden)

    Md. Akhtaruzzaman

    2013-01-01

    Full Text Available Indoline dye D-1 was successfully applied as a cosensitizer for improving the spectral response of black dye in dye-sensitized solar cells (DSCs. It was observed that D-1 effectively increases the short-circuit photocurrent by offsetting the competitive light absorption by I/I3- electrolyte in the wavelength region 350–500 nm when adsorbed on the TiO2 nanocrystaline films in a mix dye system. The DSCs containing the D-1 and black dye achieved a power conversion efficiency of 9.80% with higher short-circuit photocurrent of 19.54 mA/cm2 compared to the system of black dye without cosensitization under standard AM 1.5 sunlight.

  7. Chemical Modification on Reactive Dye Adsorption Capacity of Castor Seeds

    Directory of Open Access Journals (Sweden)

    V. Dharmalingam

    2011-01-01

    Full Text Available Abstract: The roles played by four major functional groups (amine, carboxyl, azo, hydroxyl groups in the biomass of castor seeds in adsorption of seven dyes were investigated. These functional groups in castor seeds were chemically modified individually to determine their contribution to the adsorption of ionic dyes. The dyes used were remazol red B, procino yellow, fast green FCF, brilliant cresyl blue, methylene blue, neutral red, red-141. It was found that hydroxyl group inhibited the adsorption of anionic dyes but it was major functional group in the adsorption of cationic dyes, hydroxyl group was important functional group in the adsorption of all seven dyes and the effect of methylation of amino group was not significant on the adsorption of seven dyes.

  8. Investigation of dye functional group on the photocatalytic degradation of dyes by nano-TiO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Vinu, R.; Akki, Spurti U. [Department of Chemical Engineering, Indian Institute Of Science, Bangalore, 560012, Karnataka (India); Madras, Giridhar, E-mail: giridhar@chemeng.iisc.ernet.in [Department of Chemical Engineering, Indian Institute Of Science, Bangalore, 560012, Karnataka (India)

    2010-04-15

    The photocatalytic degradation of five anionic, eight cationic and three solvent dyes using combustion-synthesized nano-TiO{sub 2} (CS TiO{sub 2}) and commercial Degussa P-25 TiO{sub 2} (DP-25) were evaluated to determine the effect of the functional group in the dye. The degradation of the dyes was quantified using the initial rate of decolorization and mineralization. The decolorization of the anionic dyes with CS TiO{sub 2} followed the order: indigo carmine > eosin Y > amido black 10B > alizarin cyanine green > orange G. The decolorization of the cationic dyes with DP-25 followed the order: malachite green > pyronin Y > rhodamine 6G > azure B > nile blue sulfate > auramine O {approx} acriflavine {approx} safranin O. CS TiO{sub 2} showed higher rates of decolorization and mineralization for all the anionic dyes compared to DP-25, while DP-25 was better in terms of decolorization for most of the cationic dyes. The solvent dyes exhibited adsorption dependent decolorization. The order of decolorization and mineralization of the anionic and cationic dyes (a) with CS TiO{sub 2} and DP-25 was different and correlated with the surface properties of these catalysts (b) were rationalized with the molecular structure of the dye and the degradation pathway of the dye.

  9. Investigation of dye functional group on the photocatalytic degradation of dyes by nano-TiO2.

    Science.gov (United States)

    Vinu, R; Akki, Spurti U; Madras, Giridhar

    2010-04-15

    The photocatalytic degradation of five anionic, eight cationic and three solvent dyes using combustion-synthesized nano-TiO(2) (CS TiO(2)) and commercial Degussa P-25 TiO(2) (DP-25) were evaluated to determine the effect of the functional group in the dye. The degradation of the dyes was quantified using the initial rate of decolorization and mineralization. The decolorization of the anionic dyes with CS TiO(2) followed the order: indigo carmine > eosin Y > amido black 10B > alizarin cyanine green > orange G. The decolorization of the cationic dyes with DP-25 followed the order: malachite green > pyronin Y > rhodamine 6G > azure B > nile blue sulfate > auramine O approximately = acriflavine approximately = safranin O. CS TiO(2) showed higher rates of decolorization and mineralization for all the anionic dyes compared to DP-25, while DP-25 was better in terms of decolorization for most of the cationic dyes. The solvent dyes exhibited adsorption dependent decolorization. The order of decolorization and mineralization of the anionic and cationic dyes (a) with CS TiO(2) and DP-25 was different and correlated with the surface properties of these catalysts (b) were rationalized with the molecular structure of the dye and the degradation pathway of the dye. 2009 Elsevier B.V. All rights reserved.

  10. Towards Rational Designing of Efficient Sensitizers Based on Thiophene and Infrared Dyes for Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Ahmad Irfan

    2014-01-01

    Full Text Available Geometries, electronic properties, and absorption spectra of the dyes which are a combination of thiophene based dye (THPD and IR dyes (covering IR region; TIRBD1-TIRBD3 were performed using density functional theory (DFT and time dependent density functional theory (TD-DFT, respectively. Different electron donating groups, electron withdrawing groups, and IR dyes have been substituted on THPD to enhance the efficiency. The bond lengths of new designed dyes are almost the same. The lowest unoccupied molecular orbital energies of designed dyes are above the conduction band of TiO2 and the highest occupied molecular orbital energies are below the redox couple revealing that TIRBD1-TIRBD3 would be better sensitizers for dye-sensitized solar cells. The broad spectra and low energy gap also showed that designed materials would be efficient sensitizers.

  11. Synthesis and dyeing performance of bisazo disperse dyes based on 3-[4-(4-amino-2-chlorophenoxyanilino]phenol

    Directory of Open Access Journals (Sweden)

    Rajesh H. Parab

    2016-09-01

    Full Text Available The present communication aims to develop bisazo disperse dyes based on 3-[4-(4-amino-2-chlorophenoxyanilino]phenol (DAP both as a coupling component as well as a diazonium salt. Coupling reaction of DAP was carried out with a diazonium salt of 4-aminoacetanilide to yield a monoazo disperse dye, and then it was further used as a diazonium salt and coupled with a different aromatic phenol to synthesize bisazo disperse dyes. All the disperse dyes were characterized by elemental analysis, IR, NMR and UV–Visible spectral studies with a view to determine their chemical structure. The dyeing ability of these bisazo disperse dyes has been evaluated in terms of their dyeing behavior and fastness properties on different fabrics.

  12. Use of the ultrasonic cavitation in wool dyeing process: Effect of the dye-bath temperature.

    Science.gov (United States)

    Actis Grande, G; Giansetti, M; Pezzin, A; Rovero, G; Sicardi, S

    2017-03-01

    The present work aims to study the effect of the liquid temperature on the performance of ultrasounds (US) in a dyeing process. The approach was both theoretical and experimental. In the theoretical part the simplified model of a single bubble implosion is used to demonstrate that the "maximum implosion pressure" calculated with the well known Rayleigh-Plesset equation for a single bubble can be correlated with the cavitation intensity experimentally measured with an Ultrasonic Energy Meter (by PPB Megasonics). In particular the model was used to study the influence of the fluid temperature on the cavitation intensity. The "relative" theoretical data calculated from the implosion pressure were satisfactorily correlated with the experimental ones and evidence a zone, between 50 and 60°C, were the cavitation intensity is almost constant and still sufficiently high. Hence an experimental part of wool dyeing was carried out both to validate the previous results and to verify the dyeing quality at low temperatures (40-70°C) in presence of US. A prototype dyeing equipment able to treat textile samples with US system of 600W power, was used. The dyeing performances in the presence and absence of US were verified by measuring ΔE (colour variation), R e,% (reflectance percentage), K/S (colour strength) and colour fastness. The US tests performed in the temperature range of 40-70°C were compared with the conventional wool dyeing at 98°C. The obtained results show that a temperature close to 60°C should be chosen as the recommended US dyeing condition, being a compromise between the cavitation intensity and the kinetics which rules the dyestuff diffusion within the fibres. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Novel diyne-bridged dyes for efficient dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Jing-Kun, E-mail: fjk@njust.edu.cn [Department of Chemistry, School of Chemical Engineering, Nanjing University of Science and Technology, Xiaolingwei Street No. 200, Nanjing, 210094 (China); Sun, Tengxiao [Department of Chemistry, School of Chemical Engineering, Nanjing University of Science and Technology, Xiaolingwei Street No. 200, Nanjing, 210094 (China); Tian, Yi [Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577 (Japan); Zhang, Yingjun, E-mail: ZhangYingjun@hec.cn [HEC Pharm Group, HEC R& D Center, Dongguan, 523871 (China); Jin, Chuanfei [HEC Pharm Group, HEC R& D Center, Dongguan, 523871 (China); Xu, Zhimin; Fang, Yu; Hu, Xiangyu; Wang, Haobin [Department of Chemistry, School of Chemical Engineering, Nanjing University of Science and Technology, Xiaolingwei Street No. 200, Nanjing, 210094 (China)

    2017-07-01

    Three new metal free organic dyes (FSD101-103) were synthesized to investigate the influence of diyne unit on dye molecules. FSD101 and FSD102 with diyne unit and FSD103 with monoyne unit were applied as sensitizers in the dye-sensitized solar cells (DSSCs). The optical and electrochemical properties, theoretical studies, and photovoltaic parameters of DSSCs sensitized by these dyes were systematically investigated. By replacing the monoyne unit with a diyne unit, FSD101 exhibited broader absorption spectrum, lower IP, higher EA, lower band gap energy, higher oscillator strength, more efficient electron injection ability, broader IPCE response range and higher τ{sub e} in comparison with FSD103. Hence, DSSC sensitized by FSD101 showed higher J{sub sc} and V{sub oc} values, and demonstrated a power conversion efficiency of 3.12%, about 2-fold as that of FSD103 (1.55%). FSD102 showed similar results as FSD101, with a power conversion efficiency of 2.98%, despite a stronger electron withdraw cyanoacrylic acid group was introduced. This may be due to the lower efficiency of the electron injection from dye to TiO{sub 2} and lower τ{sub e} of FSD102 than that of FSD101. These results indicate that the performance of DSSCs can be significantly improved by introducing a diyne unit into this type of organic dyes. - Highlights: • Diyne-bridge was introduced into dye molecules by a transition-metal-free protocol. • Power conversion efficiency grows from 1.55% to 3.12% by replacing monoyne unit with diyne unit. • FSD101 with diyne unit shows the highest electron lifetime resulting in a higher V{sub oc}.

  14. Detoxification of azo dyes in the context of environmental processes.

    Science.gov (United States)

    Rawat, Deepak; Mishra, Vandana; Sharma, Radhey Shyam

    2016-07-01

    Azo dyes account for >70% of the global industrial demand (∼9 million tons). Owing to their genotoxic/carcinogenic potential, the annual disposal of ∼4,500,000 tons of dyes and/or degraded products is an environmental and socio-economic concern. In comparison to physico-chemical methods, microbe-mediated dye degradation is considered to be low-input, cost-effective and environmentally-safe. However, under different environmental conditions, interactions of chemically diverse dyes with metabolically diverse microbes produce metabolites of varying toxicity. In addition, majority of studies on microbial dye-degradation focus on decolorization with least attention towards detoxification. Therefore, the environmental significance of microbial dye detoxification research of past >3 decades is critically evaluated with reference to dye structure and the possible influence of microbial interactions in different environments. In the absence of ecosystem-based studies, the results of laboratory-based studies on dye degradation, metabolite production and their genotoxic impact on model organisms are used to predict the possible fate and consequences of azo dyes/metabolites in the environment. In such studies, the predominance of fewer numbers of toxicological assays that too at lower levels of biological organization (molecular/cellular/organismic) suggests its limited ecological significance. Based on critical evaluation of these studies the recommendations on inclusion of multilevel approach (assessment at multiple levels of biological organization), multispecies microcosm approach and native species approach in conjunction with identification of dye metabolites have been made for future studies. Such studies will bridge the gap between the fundamental knowledge on dye-microbe-environment interactions and its application to combat dye-induced environmental toxicity. Thus an environmental perspective on dye toxicity in the background of dye structure and effects of

  15. Imaging Prostate Cancer Microenvironment by Collagen Hybridization

    Science.gov (United States)

    2016-10-01

    transconjugated dye-labeled serum proteins . 13   Future Plans The PCa imaging in animal model was mainly conducted in the lab of Dr. Pomper at the Johns...the dye can transfer from CMP onto serum proteins (e.g. albumin) resulting in an unexpected drop in signal during serum stability assays and off...specifically target digested collagens with unfolded and partially denatured collagen triple helices. 2. Demonstration of ex vivo and in vivo targeting

  16. Dye-sensitized nanocrystalline TiO{sub 2} solar cells based on novel coumarin dyes

    Energy Technology Data Exchange (ETDEWEB)

    Hara, Kohjiro; Tachibana, Yasuhiro; Sayama, Kazuhiro; Sugihara, Hideki; Arakawa, Hironori [National Inst. of Advanced Industrial Science and Technology, Ibaraki (Japan). Photoreaction Control Research Center; Ohga, Yasuyo; Shinpo, Akira; Suga, Sadaharu [Hayashibara Biochemical Labs., Okayama (Japan)

    2003-04-30

    We have developed dye-sensitized nanocrystalline TiO{sub 2} solar cells (DSSCs) based on novel coumarin-dye photosensitizers. The absorption spectra of these novel dyes are red-shifted remarkably in the visible region relative to the spectrum of C343, a conventional coumarin dye. Introduction of a methine unit (-CH=CH-) connecting the cyano (-CN) and carboxyl (-COOH) groups into the coumarin framework expanded the {pi}-conjugation in the dye and thus resulted in a wide absorption in the visible region. These novel dyes performed as efficient photosensitizers for DSSCs. A DSSC based on 2-cyano-5-(1,1,6,6-tetramethyl-10-oxo-2,3,5,6-tetrahydro-1H,4H,10H-11-oxa-3a-a= za-benzo[de]anthracen-9-yl)-penta-2,4-dienoic acid (NKX-2311), produced a 6.0% solar energy-to-electricity conversion efficiency ({eta}), the highest performance among DSSCs based on organic-dye photosensitizers, under AM 1.5 irradiation (100 mW cm{sup -2}) with a short-circuit current density (J{sub sc}) of 14.0 mA cm{sup -2}, an open-circuit voltage (V{sub oc}) of 0.60 V, and a fill factor of 0.71. Our results suggests that the structure of NKX-2311 whose carboxyl group is directly connected to the -CH=CH- unit, is advantageous for effective electron injection from the dye into the conduction band of TiO{sub 2}. In addition, the cyano group, owing to its strong electron-withdrawing ability, might play an important role in electron injection in addition to a red shift in the absorption region. On a long-term stability test under continuous irradiation with white light (80 mW cm{sup -2}), stable performance was attained with a solar cell based on the NKX-2311 dye with a turnover number of 2.6x10{sup 7} per one molecule. (Author)

  17. Dye-sensitized nanocrystalline TiO{sup 2} solar cells based on novel coumarin dyes

    Energy Technology Data Exchange (ETDEWEB)

    Hara, Kohjiro; Tachibana, Yasuhiro; Sayama, Kazuhiro; Sugihara, Hideki; Arakawa, Hironori [Photoreaction Control Research Center (PCRC) Science and Technology, National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565 (Japan); Ohga, Yasuyo; Shinpo, Akira; Suga, Sadaharu [Hayashibara Biochemical Laboratories, Inc., 564-176 Fujita, Okayama 701-0221 (Japan)

    2003-04-30

    We have developed dye-sensitized nanocrystalline TiO{sub 2} solar cells (DSSCs) based on novel coumarin-dye photosensitizers. The absorption spectra of these novel dyes are red-shifted remarkably in the visible region relative to the spectrum of C343, a conventional coumarin dye. Introduction of a methine unit (-CH==CH-) connecting the cyano (-CN) and carboxyl (-COOH) groups into the coumarin framework expanded the {pi}-conjugation in the dye and thus resulted in a wide absorption in the visible region. These novel dyes performed as efficient photosensitizers for DSSCs. A DSSC based on 2-cyano-5-(1,1,6,6-tetramethyl-10-oxo-2,3,5,6-tetrahydro-1H,4H,10H-11-oxa-3a- aza-benzo[de]anthracen-9-yl)-penta-2,4-dienoic acid (NKX-2311), produced a 6.0% solar energy-to-electricity conversion efficiency ({eta}), the highest performance among DSSCs based on organic-dye photosensitizers, under AM 1.5 irradiation (100mWcm{sup -2}) with a short-circuit current density (J{sub sc}) of 14.0mAcm{sup -2}, an open-circuit voltage (V{sub oc}) of 0.60V, and a fill factor of 0.71. Our results suggests that the structure of NKX-2311 whose carboxyl group is directly connected to the -CH==CH- unit, is advantageous for effective electron injection from the dye into the conduction band of TiO{sub 2}. In addition, the cyano group, owing to its strong electron-withdrawing ability, might play an important role in electron injection in addition to a red shift in the absorption region. On a long-term stability test under continuous irradiation with white light (80mWcm{sup -2}), stable performance was attained with a solar cell based on the NKX-2311 dye with a turnover number of 2.6x10{sup 7} per one molecule.

  18. Investigation of TiO 2 /zeolite photocatalytic activity for Safranin dye removal of aqueous solution

    Directory of Open Access Journals (Sweden)

    Masoud Rismanchian

    2015-01-01

    Full Text Available Aims: This study was aimed to determine the TiO 2 /zeolite photocatalytic activity for removing red Safranin dye form aqueous phase. Materials and Methods: In this study, TiO 2 nanoparticles were produced using sol-gel method and 2.5 ml sol-gel was coated on 1.2222 g of zeolite. X-ray diffraction (XRD and scanning electron microscopy (SEM were applied to specify the structure and morphology of TiO 2 nanoparticles. The effect of TiO 2 coating on zeolite, ultraviolet (UV radiation intensity, initial concentration of dye and the type of photocatalyst substrate (fixed and moving on photocatalytic process was investigated. Results: According to XRD results, the TiO 2 nanoparticles had two phases including anatase (80.5% and rutile (19.5%. The uniformity of nanoparticles was obvious in the SEM images. The removal efficiency of TiO 2 coated on zeolite was higher than TiO 2 photocatalysis with increasing UV radiation intensity from 2.4 w/m 2 to 3.9 w/m 2 , the photocatalytic efficiency was also enhanced. The removal efficiency decreased from 91.61% to 77.91% by increasing the red Safranin dye concentration from 10 mg/L to 50 mg/L. The moving bed of TiO 2 /zeolite photocatalyst had a higher efficiency than the fixed bed. Conclusion: In over all, the TiO 2 /zeolite photocatalyst was much more effective than TiO 2 photocatalyst for Safranin dye removal from the aqueous phase. With increasing UV radiation intensity and decreasing dye concentration photocatalytic efficiency, was improved. TiO 2 /zeolite photocatalyst with fixed bed is recommended to be used in water treatment. The most important problem of using moving-bed TiO 2 /zeolite photocatalyst in the water treatment is opacity.

  19. Nanoimprinted polymer photonic crystal dye lasers

    DEFF Research Database (Denmark)

    Christiansen, Mads Brøkner; Smith, Cameron; Buss, Thomas

    2010-01-01

    Optically pumped polymer photonic crystal band-edge dye lasers are presented. The photonic crystal is a rectangular lattice providing laser feedback as well as an optical resonance for the pump light. The lasers are defined in a thin film of photodefinable Ormocore hybrid polymer, doped...... with the laser dye Pyrromethene 597. A compact frequency doubled Nd:YAG laser (352 nm, 5 ns pulses) is used to pump the lasers from above the chip. The laser devices are 450 nm thick slab waveguides with a rectangular lattice of 100 nm deep air holes imprinted into the surface. The 2-dimensional rectangular...... lattice is described by two orthogonal unit vectors of length a and b, defining the P and X directions. The frequency of the laser can be tuned via the lattice constant a (187 nm - 215 nm) while pump light is resonantly coupled into the laser from an angle () depending on the lattice constant b (355 nm...

  20. Yellow Dye Extraction from Eucalyptus Grandis Bark.

    OpenAIRE

    Chengeto Zvavamwe; Cathrine Khetiwe Mkandhla; Clever Mpofu; Vernon Phiri; Felicity Bgwoni; Bettina Khonzokuhle Ncube; Mafika Sibutha; Joel Tshuma

    2016-01-01

    In this article, yellow dye was extracted from Eucalyptus Grandis bark using methanol solvent at a temperature of 250C and pressure of 1 atmosphere. The extraction process was optimized by varying extraction material-to-liquor ratio, in the ratios of 1:100, 1:50, 3:100, 1:25, 1:20, 3:50, 7:100, 2:25, 9:100 and 1:10. The extraction pH was varied from 1 to 13 at an interval of pH 1. The mass of the dye extract was found to be directly proportional to the mass of the bark at each pH. The optimum...

  1. Solvatochromic dyes detect the presence of homeopathic potencies.

    Science.gov (United States)

    Cartwright, Steven J

    2016-02-01

    A systematic approach to the design of simple, chemical systems for investigating the nature of homeopathic medicines has led to the development of an experimental protocol in which solvatochromic dyes are used as molecular probes of serially diluted and agitated solutions. Electronic spectroscopy has been used to follow changes in the absorbance of this class of dyes across the visible spectrum in the presence of homeopathic potencies. Evidence is presented using six different solvatochromic dyes in three different solvent systems. In all cases homeopathic potencies produce consistent and reproducible changes in the spectra of the dyes. Results suggest that potencies influence the supramolecular chemistry of solvatochromic dyes, enhancing either dye aggregation or disaggregation, depending upon dye structure. Comparable dyes lacking the intramolecular charge transfer feature of solvatochromic dyes are unaffected by homeopathic potencies, suggesting potencies require the oscillating dipole of solvatochromic dyes for effective interaction. The implications of the results presented, both for an eventual understanding of the nature of homeopathic medicines and their mode of action, together with future directions for research in this area, are discussed. Copyright © 2015 The Author. Published by Elsevier Ltd.. All rights reserved.

  2. Knowledge, attitude, and practice of dyeing and printing workers

    Directory of Open Access Journals (Sweden)

    Paramasivam Parimalam

    2010-01-01

    Full Text Available Background: Millions of workers are occupationally exposed to dyes in the world, but little is known about their knowledge and attitudes toward the effects of dye on their health. Objectives: The aim of this study was to assess the fabric dyers′ and fabric printers′ knowledge, attitude, and practice toward the health hazard of dyes. Materials and Methods: The present study was taken up in the Madurai district which is situated in the Southern Tamil Nadu, India. One hundred and forty-two workers employed in small-scale dyeing and printing units participated in a face-to-face confidential interview . Results: The mean age of fabric dyers and fabric printers was 42 years (΁10.7. When enquired about whether dyes affect body organ(s, all the workers agreed that dye(s will affect skin, but they were not aware that dyes could affect other parts of the body. All the workers believed that safe methods of handling of dyes and disposal of contaminated packaging used for dyes need to be considered. It was found that 34% of the workers were using personal protective equipment (PPE such as rubber hand gloves during work. Conclusion: The workers had knowledge regarding the occupational hazards, and their attitudinal approach toward the betterment of the work environment is positive.

  3. Knowledge, attitude, and practice of dyeing and printing workers.

    Science.gov (United States)

    Paramasivam, Parimalam; Raghavan, Premalatha Mundankandath; Srinivasan, Padmini Dasu; Kumar, Ganguli Anindya

    2010-10-01

    Millions of workers are occupationally exposed to dyes in the world, but little is known about their knowledge and attitudes toward the effects of dye on their health.. The aim of this study was to assess the fabric dyers' and fabric printers' knowledge, attitude, and practice toward the health hazard of dyes. The present study was taken up in the Madurai district which is situated in the Southern Tamil Nadu, India. One hundred and forty-two workers employed in small-scale dyeing and printing units participated in a face-to-face confidential interview. The mean age of fabric dyers and fabric printers was 42 years (±10.7). When enquired about whether dyes affect body organ(s), all the workers agreed that dye(s) will affect skin, but they were not aware that dyes could affect other parts of the body. All the workers believed that safe methods of handling of dyes and disposal of contaminated packaging used for dyes need to be considered. It was found that 34% of the workers were using personal protective equipment (PPE) such as rubber hand gloves during work. The workers had knowledge regarding the occupational hazards, and their attitudinal approach toward the betterment of the work environment is positive.

  4. The pattern of hair dyeing in koreans with gray hair.

    Science.gov (United States)

    Jo, Seong Jin; Shin, Hyoseung; Paik, Seung Hwan; Choi, Jae Woo; Lee, Jong Hee; Cho, Soyun; Kwon, Ohsang

    2013-11-01

    Hair graying is considered as a part of normal ageing process. Nonetheless, this process raises a significant cosmetic concern, especially among ethnic Korean elderly whose baseline hair color is black. For this reason, Korean elderly dye their hair with frequency despite the risk of dermatologic problems such as allergic contact dermatitis. In this study, the authors investigate the prevalence and pattern of hair dyeing and its relation with scalp diseases in Korea. Six hundred twenty subjects (330 men and 290 women) with graying hair were given a questionnaire survery and underwent a physical examination. Of the 620 total, 272 subjects (43.9%) dyed their hair. Hair dyeing was significantly more frequent among women than among men (phair dyeing when compared to either younger or older groups. Subjective self-assessment of the extent of hair graying was associated with increased prevalence of hair dyeing, that is, individuals who feel graying has advanced by more than 20% of the overall hair were much more likely to dye their hair (pHair dyeing did not correlate with either alopecia or scalp disease. Our survey has found that the prevalence of hair dyeing is higher among Korean women than men. People in their fifties and sixties and people with more than 20% extent of grayness were more likely to dye their hair than otherwise. Hair dyeing was not associated with any increase in the prevalence of scalp diseases.

  5. Degradation of azo dyes by environmental microorganisms and helminths

    Energy Technology Data Exchange (ETDEWEB)

    Kingthom Chung; Stevens, S.E. Jr. (Memphis State Univ., TN (United States). Dept. of Biology)

    1993-11-01

    The degradation of azo dyes by environmental microorganisms, fungi, and helminths is reviewed. Azo dyes are used in a wide variety of products and can be found in the effluent of most sewage treatment facilities. Substantial quantities of these dyes have been deposited in the environment, particularly in streams and rivers. Azo dyes were shown to affect microbial activities and microbial population sizes in the sediments and in the water columns of aquatic habitats. Only a few aerobic bacteria have been found to reduce azo dyes under aerobic conditions, and little is known about the process. A substantial number of anaerobic bacteria capable of azo dye reduction have been reported. The enzyme responsible for azo dye reduction has been partially purified, and characterization of the enzyme is proceeding. The nematode Ascaris lumbricoides and the cestode Moniezia expanza have been reported to reduce azo dyes anaerobically. Recently the fungus Phanerochaete chrysoporium was reported to mineralize azo dyes via a peroxidation-mediated pathway. A possible degradation pathway for the mineralization of azo dye is proposed and future research needs are discussed.

  6. Radiocontrast Dye Extravasation During Sialography.

    Science.gov (United States)

    Truong, Kristy; Hoffman, Henry T; Policeni, Bruno; Maley, Joan

    2018-01-01

    Evaluate the pathophysiology of contrast extravasation. Two hundred fifty-five sialograms at the University of Iowa from 2008 to 2016 were reviewed. Twelve sialograms (4.7% of total) were identified with main ductal extravasation. In each case, ductal stenosis as a diagnosis was supported by clinical history and the finding of difficulty in advancing the cannula into the duct during sialography. In all but 1 case, extravasation occurred at the distal duct with no further imaging of the ductal system. Each of the 5 cases treated with sialendoscopy with or without gland resection confirmed stenosis. Ultrasound evaluation of 5 of the cases detected ductal dilation in 4 (80%). Six of 11 computed tomography scans done before the sialogram were interpreted as normal with indirect evidence for ductal stenosis (duct dilation) reported in only 1. All extravasations were associated with either stricture alone or stricture with stone (1 case). Radiocontrast extravasation from the main duct during sialography is highly associated with the presence of ductal stricture. In our experience, the inability to fill the ductal system with radiocontrast is a useful sialographic finding that correlated closely with anatomic abnormality rather than technical error. The frequent finding of extravasation of radiocontrast supports the use of water soluble contrast.

  7. Novel conjugated organic dyes for efficient dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Hara, K.; Sato, T.; Katoh, R.; Furube, A.; Yoshihara, T.; Murai, M.; Kurashige, M.; Arakawa, H. [National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565 (Japan); Ito, S.; Shinpo, A.; Suga, S. [Hayashibara Biochemical Laboratories, Inc., 564-176 Fujita, Okayama 701-0221 (Japan)

    2005-02-01

    Novel conjugated organic dyes that have N,N-dimethylaniline (DMA) moieties as the electron donor and a cyanoacetic acid (CAA) moiety as the electron acceptor were developed for use in dye-sensitized nanocrystalline-TiO{sub 2} solar cells (DSSCs). We attained a maximum solar-energy-to-electricity conversion efficiency ({eta}) of 6.8 % under AM 1.5 irradiation (100 mW cm{sup -2}) with a DSSC based on 2-cyano-7,7-bis(4-dimethylamino-phenyl)hepta-2,4,6-trienoic acid (NKX-2569): short-circuit photocurrent density (J{sub sc}) = 12.9 mA cm{sup -2}, open-circuit voltage (V{sub oc}) = 0.71 V, and fill factor (ff) = 0.74. The high performance of the solar cells indicated that highly efficient electron injection from the excited dyes to the conduction band of TiO{sub 2} occurred. The experimental and calculated Fourier-transform infrared (FT-IR) absorption spectra clearly showed that these dyes were adsorbed on the TiO{sub 2} surface with the carboxylate coordination form. A molecular-orbital calculation indicated that the electron distribution moved from the DMA moiety to the CAA moiety by photoexcitation of the dye. (Abstract Copyright [2005], Wiley Periodicals, Inc.)

  8. Comparative Testis Tissue Proteomics Using 2-Dye Versus 3-Dye DIGE Analysis.

    Science.gov (United States)

    Holland, Ashling

    2018-01-01

    Comparative tissue proteomics aims to analyze alterations of the proteome in response to a stimulus. Two-dimensional difference gel electrophoresis (2D-DIGE) is a modified and advanced form of 2D gel electrophoresis. DIGE is a powerful biochemical method that compares two or three protein samples on the same analytical gel, and can be used to establish differentially expressed protein levels between healthy normal and diseased pathological tissue sample groups. Minimal DIGE labeling can be used via a 2-dye system with Cy3 and Cy5 or a 3-dye system with Cy2, Cy3, and Cy5 to fluorescently label samples with CyDye flours pre-electrophoresis. DIGE circumvents gel-to-gel variability by multiplexing samples to a single gel and through the use of a pooled internal standard for normalization. This form of quantitative high-resolution proteomics facilitates the comparative analysis and evaluation of tissue protein compositions. Comparing tissue groups under different conditions is crucially important for advancing the biomedical field by characterization of cellular processes, understanding pathophysiological development and tissue biomarker discovery. This chapter discusses 2D-DIGE as a comparative tissue proteomic technique and describes in detail the experimental steps required for comparative proteomic analysis employing both options of 2-dye and 3-dye DIGE minimal labeling.

  9. Comparing the mode of action of intraocular lutein-based dyes with synthetic dyes.

    Science.gov (United States)

    Sousa-Martins, Diogo; Caseli, Luciano; Figueiredo, Mafalda C; Sa E Cunha, Claudia; Mota-Filipe, Helder; Souza-Lima, Acácio; Belfort, Rubens; Rodrigues, Eduardo; Maia, Mauricio

    2015-02-19

    To investigate and compare the mechanism by which lutein-based and synthetic intraocular dyes interact with their target membranes during ophthalmic surgeries. Surrogate membrane models were used in order to simulate the different intraocular membranes: internal limiting membrane (ILM), vitreous, anterior capsule (AC), and epiretinal membrane (ERM). Different lutein-based dyes, such as Phacodyne, Retidyne, Retidyne Plus, and Vitreodyne were tested, as well as Trypan Blue (TB), Indocyanine Green (ICG), Brilliant Blue (BB), and Triamcinolone Acetonide (TA). The interactions between the film components occurring at the air-water interface were investigated with surface pressure-area isotherms and polarization modulation infrared reflection-absorption spectroscopy (PM-IRRAS). With the exception of TA and ICG, none of the tested dyes revealed toxicity to the analyzed membranes. The interaction of TA with the vitreous model affected deeply the biointerface structure of the model. A significant condensation of the monolayer is noted when ICG contacted with ILM by the isotherms or even a solubilization of part of the monolayer toward the aqueous subphase. Retidyne Plus may provide the fluidization of the membrane, but maintains intact the structure of proteins present in the model. The present study demonstrates for the first time that lutein-based dyes interact through a physical mechanism of action with membrane models of structures present in human eye. On the other hand, the chemical interaction of synthetic dyes TA and ICG resulted in an alteration of the membrane models. Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.

  10. Treatment of Direct Blending Dye Wastewater and Recycling of Dye Sludge

    Directory of Open Access Journals (Sweden)

    Ming-Li Li

    2012-03-01

    Full Text Available A new sorbent material, barium sulfate-Direct Blending Yellow D-3RNL hybrid (BSD, was synthesized and characterized by various methods. Both the anionic dyes, Reactive Brilliant Red X-3B and Weak Acid Green GS were hardly adsorbed by the BSD material, while the sorption of Ethyl Violet (EV and Victoria Blue B were extremely obvious. The sorption of cationic dyes obeyed the Langmuir isotherm model, which depended on the electric charge attraction. The saturation amount of EV adsorbed onto the BSD material approached to 39.36 mg/g. The sorption of EV changed little with pH from 3 to 12 while it increased with increasing levels of electrolyte. A dye wastewater sampled from Jinjiang Chemicals was treated, and the color removal rate was more than the COD removal rate. In addition, the cationic dye-BSD sludge was utilized as a colorant fill-in coating. The light stability and thermal stability of the colorant was measured and exhibited good features. This work provided a simple and eco-friendly method for dye wastewater treatment with recycling of waste.

  11. Effects of reduction products of ortho-hydroxyl substituted azo dyes on biodecolorization of azo dyes

    Energy Technology Data Exchange (ETDEWEB)

    Liu Guangfei [Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental and Biological Science and Technology, Dalian University of Technology, Linggong Road No. 2, Dalian 116024 (China); Wang Jing, E-mail: wangjingbio@yahoo.cn [Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental and Biological Science and Technology, Dalian University of Technology, Linggong Road No. 2, Dalian 116024 (China); Lu Hong; Jin Ruofei; Zhou Jiti; Zhang Long [Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental and Biological Science and Technology, Dalian University of Technology, Linggong Road No. 2, Dalian 116024 (China)

    2009-11-15

    The mediated effects of reduction products of some ortho-hydroxyl substituted azo dyes on biodecolorization were investigated. The results indicated that the addition of reduction products could effectively accelerate dye decolorization by Shigella sp. QRZ-1. The best accelerating effect was obtained with the addition of reduction products of Acid Red 14 (AR14), resulting in an over 3-fold increase in decolorization efficiency of many azo dyes. In sequencing batch reactor experiments, the accelerating effect of reduction products of AR14 was more obvious (1.5-fold) during the startup of the system. When the dye concentration was increased to 500 mg L{sup -1}, the accelerated decolorization efficiency was still maintained around 95%. The presence of AR14 in the feed enhanced the decolorization performance of anaerobic sludge, indicating that the strategy may be beneficial for practical application. 1-Naphthol-2-amino-4-sulfonic acid, which is one of the reduction products of AR14, may function as redox mediator to speed up azo dye biodecolorization.

  12. Time dependent – density functional theory characterization of organic dyes for dye-sensitized solar cells

    KAUST Repository

    Hilal, Rifaat

    2017-06-19

    We aim at providing better insight into the parameters that govern the intramolecular charge transfer (ICT) and photo-injection processes in dyes for dye-sensitised solar cells (DSSC). Density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations are utilized to study the geometry, electronic structure, electrostatic potential (ESP) and absorption spectrum, for a representative donor-π bridge-acceptor (D–π–A) dye for DSSC. The coplanar geometry of the dye (D1) facilitates strong conjugation and considerable delocalization originating the π CT interaction from donor to acceptor orbitals and the hyper-conjugative interactions involving Rydberg states. A model simulating the adsorption of the dye on the TiO surface is utilized to estimate binding energies. The effect of fluorine substituents in the π-spacer on the quantum efficiency of DSSCs was investigated. Gibb’s free energy values, redox potentials, excited state lifetime, non-linear optical properties (NLO) and driving forces for D1 and its fluorinated derivatives were computed.

  13. Novel organic dyes based on phenyl-substituted benzimidazole for dye sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Saltan, Gözde Murat [Department of Chemistry, Faculty of Arts and Science, Celal Bayar University, Yunus Emre, 45140 Manisa (Turkey); Dinçalp, Haluk, E-mail: haluk.dincalp@cbu.edu.tr [Department of Chemistry, Faculty of Arts and Science, Celal Bayar University, Yunus Emre, 45140 Manisa (Turkey); Kıran, Merve; Zafer, Ceylan [Solar Energy Institute, Ege University, Bornova, 35100 Izmir (Turkey); Erbaş, Seçil Çelik [Celal Bayar University, Materials Engineering Department, Faculty of Engineering, Yunus Emre, 45140 Manisa (Turkey)

    2015-08-01

    Two new sensitizers derived from benzimidazole core for dye-sensitized solar cell (DSSC) applications were designed and synthesized as D–π–A structures, in which two phenyl-substituted benzimidazole group, a phenyl ring and a cyanoacrylic acid were used as the electron donor, π-conjugated linkage and the electron acceptor, respectively. Effect of methoxy- and N,N-dimetylamino- moieties attached to the phenyl groups of benzimidazole were investigated by means of optical and photovoltaic measurements. The compounds exhibit broad absorption maximum at 387 nm with the tail extending up to 500 nm on TiO{sub 2}-coated thin film. The longer wavelength absorption band around 360 nm and the much longer decay components could be attributed to the existence of charge transfer state of the dyes in solutions. DSSC device fabricated by using methoxy substituted dye (BI5a) as a sensitizer shows much better incident photon-to-current conversion efficiency (IPCE) of 64% giving cell efficiency of 2.68%. - Graphical abstract: Display Omitted - Highlights: • Long decay times suggest the delayed fluorescence caused by the existence of ICT. • The best solar energy conversion efficiency was obtained for BI5a dye (2.68%). • More fluorescent BI5a dye gives higher photocurrent generation.

  14. Medical imaging systems

    Energy Technology Data Exchange (ETDEWEB)

    Frangioni, John V [Wayland, MA

    2012-07-24

    A medical imaging system provides simultaneous rendering of visible light and fluorescent images. The system may employ dyes in a small-molecule form that remains in a subject's blood stream for several minutes, allowing real-time imaging of the subject's circulatory system superimposed upon a conventional, visible light image of the subject. The system may also employ dyes or other fluorescent substances associated with antibodies, antibody fragments, or ligands that accumulate within a region of diagnostic significance. In one embodiment, the system provides an excitation light source to excite the fluorescent substance and a visible light source for general illumination within the same optical guide that is used to capture images. In another embodiment, the system is configured for use in open surgical procedures by providing an operating area that is closed to ambient light. More broadly, the systems described herein may be used in imaging applications where a visible light image may be usefully supplemented by an image formed from fluorescent emissions from a fluorescent substance that marks areas of functional interest.

  15. SUITABLE MORDANTS FOR DYEING POSIDONIA OCEANICA FIBERS

    Directory of Open Access Journals (Sweden)

    ROMÁN Silvia

    2017-05-01

    Full Text Available Posidonia oceanica is the most extended sea grass in the Mediterranean Sea. Important quantities of this alga are accumulated on coasts making necessary the cleaninness of those beaches where it can be found. For this reason, many authors are developmenting new products made by this raw material, like green composites or are studing this material to be used as biomass, for example. The aim of this study is to dye the Posidonia Oceanica fiber using commercial natural dye to change their appearance to get a material more attractive for different areas. To achieve this aim, fibers were scoured and bleached in order to remove the brown colour of the Posidonia Oceanica fibers. Scoured and bleached processes were followed by the treatment done for cellulosic fibers, because some researches indicate that P. Oceanica is composed of high quantity of cellulose. Different types of biomordants were use in the pre-treatment of the fiber to improve the affinity between the fiber and the dye used. To compare the results, we evaluate the colour of each sample using CIELAB parameters and colour differences (ΔE*, which are obtained by reflexion spectrophotometre. The results showed that medium molecular weight chitosan, which was used as biomordant, gets the highest intensity of colour

  16. Plastic encapsulated, dye sensitised photovoltaic cells

    Energy Technology Data Exchange (ETDEWEB)

    Potter, R.J.; Otley, L.C.; Durrant, J.R.; Haque, S.; Xu, C. [Imperial College of Science, Technology and Medicine, London (United Kingdom); Holmes, A.B.; Park, T.; Schulte, N. [Cambridge Univ. (United Kingdom)

    2004-07-01

    The report presents the results of a collaborative project that aimed to demonstrate the technical feasibility of a plastic-encapsulated, solid state, dye-sensitised solar cell (DSSC) with an energy conversion efficiency (ECE) of at least 3%. DSSCs offer a possible 'step change' in photovoltaic technology resulting in lower costs compared with existing technologies. The project involved a series of eight main tasks: the development of first and second generation HTM electrolytes; the development of polymer-supported electrolytes; the development of low temperature electrode coating procedures; dye development; cell assembly and testing; component integration; and overall process development. A wide range of innovative HTMs have been synthesised, including materials incorporating both hole-transporting and ion-chelating functional groups. The ruthenium-based dye, N3, remained the preferred sensitising component. The project has produced a system that can routinely achieve over 5% ECE at 0.1 Sun illumination on 1 cm{sup 2} cells using polymer-supported electrolytes.

  17. Patent blue dye in lymphaticovenular anastomosis.

    Science.gov (United States)

    Yap, Yan Lin; Lim, Jane; Shim, Timothy W H; Naidu, Shenthilkumar; Ong, Wei Chen; Lim, Thiam Chye

    2009-08-01

    Lymphaticovenular anastomosis (LVA) has been described as a treatment of chronic lymphoedema. This microsurgical technique is new and technically difficult. The small caliber and thin wall lymphatic vessels are difficult to identify and easily destroyed during the dissection. We describe a technique of performing lymphaticovenular anastomosis with patent blue dye enhancement. Our patient is a 50-year-old lady who suffers from chronic lymphoedema of the upper limb after mastectomy and axillary clearance for breast cancer 8 years ago. Patent blue dye is injected subdermally and is taken up readily by the draining lymphatic channels. This allows for easy identification of their course. The visualisation of the lumen of the lymphatic vessel facilitates microsurgical anastomosis. The patency of the anastomosis is also demonstrated by the dynamic pumping action of the lymphatic within the vessels. Patent blue dye staining during lymphaticovenular anastomosis is a simple, effective and safe method for mapping suitable subdermal lymphatics, allowing for speedier dissection of the lymphatic vessels intraoperatively. This technique also helps in the confirmation of the success of the lymphaticovenular anastomosis.

  18. Confinement of pyridinium hemicyanine dye within an anionic metal-organic framework for two-photon-pumped lasing

    Science.gov (United States)

    Yu, Jiancan; Cui, Yuanjing; Xu, Hui; Yang, Yu; Wang, Zhiyu; Chen, Banglin; Qian, Guodong

    2013-10-01

    Two-photon-pumped dye lasers are very important because of their applications in wavelength up-conversion, optical data storage, biological imaging and photodynamic therapy. Such lasers are very difficult to realize in the solid state because of the aggregation-caused quenching. Here we demonstrate a new two-photon-pumped micro-laser by encapsulating the cationic pyridinium hemicyanine dye into an anionic metal-organic framework (MOF). The resultant MOF⊃dye composite exhibits significant two-photon fluorescence because of the large absorption cross-section and the encapsulation-enhanced luminescent efficiency of the dye. Furthermore, the well-faceted MOF crystal serves as a natural Fabry-Perot resonance cavity, leading to lasing around 640 nm when pumped with a 1064-nm pulse laser. This strategy not only combines the crystalline benefit of MOFs and luminescent behaviour of organic dyes but also creates a new synergistic two-photon-pumped lasing functionality, opening a new avenue for the future creation of solid-state photonic materials and devices.

  19. Removal of azo dye acid orange 7 using aerobic membrane bioreactor

    Directory of Open Access Journals (Sweden)

    A.H. Konsowa

    2011-03-01

    Full Text Available A laboratory scale aerobic membrane bioreactor (MBR using a submerged microfiltration (MF; hollow-fiber membrane was used for treating wastewater polluted with azo dye acid orange 7 (AO7. Initial dye concentrations studied were from 50 to 400 mg/l with a COD ranging from 95 to 550 mg O2/l and hydraulic retention times (HRT 4, 6, 8 and 24 h. Results showed that the biological process was responsible for almost 60–80% of COD removal and almost all the removal of AO7 color. Membrane microfiltration merely balanced the unstable biological treatment of COD and demonstrated almost no contribution to AO7 color removal. Trans-membrane pressure (TMP increased with time, and with the increase of dye concentration reaching a maximum of 4.175 psi. Scanning electron microscope (SEM images of the membrane’s filament were taken and compared with a SEM image of a virgin membrane; clear deformation in membrane’s pore structure could be noticed as well as scale formation on the outer surface of filaments, foulants were determined using the energy dispersive X-ray analysis (EDX.

  20. First-principles study of Carbz-PAHTDDT dye sensitizer and two Carbz-derived dyes for dye sensitized solar cells

    CERN Document Server

    Mohammadi, Narges

    2014-01-01

    Two new carbazole-based organic dye sensitizers are designed and investigated in silico. These dyes are designed through chemical modifications of the conjugated bridge of a reference organic sensitizer known as Carbz-PAHTDDT (S9) dye. The aim of designing these dyes was to reduce the energy gap between their highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) and to red-shift their absorption response compared to those of the reference S9 dye sensitizer. This reference dye has a reported promising efficiency when coupled with ferrocene-based electrolyte composition. To investigate geometric and electronic structure, density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations were conducted on the new dyes as well as the reference dye. The present study indicated that the long-range correction to the theoretical model in the TD-DFT simulation is important to produce accurate absorption wavelengths.The theoretical studies have shown a reduced HOMO-LUMO gap ...

  1. The comparison of spectra and dyeing properties of new azonaphthalimide with analogues azobenzene dyes on natural and synthetic polymers

    Directory of Open Access Journals (Sweden)

    Mozhgan Hosseinnezhad

    2017-05-01

    Full Text Available The aim of the present research was to prepare new acid dyes based on naphthalimides. In this respect a series of monoazo acid dyes have been obtained using 4-amino-N-methyl (alternatively N-butyl-1,8-naphthalimide, aniline and p-nitroaniline as diazo components. 2-Naphthol-6-sulfonic acid (Schaeffer’s acid and 1-naphthol-8-amino-3,6-disulfonic acid (H-acid were used as coupling components. The spectrophotometric properties of the synthesized dyes were investigated in various solvents and compared with analogues azobenzene dyes. It is found, when acid dyes are applied in various solvents and different pH, additional bathochromically shifted bands of different intensity appear in the electronic spectra. This effect is caused by the occurrence of the equilibrium of azo and hydrazone forms in the dyes. The synthesized acid dyes were applied on wool fabrics in order to consider their dyeing properties, fastnesses and the obtainable color gamut. The synthesized dyes represented that they have the ability of dyeing wool and polyamide fabrics and give red to violet hues with good wash, medium light, and good milling and perspiration fastnesses.

  2. Synthesis and investigation of antimicrobial activity and spectrophotometric and dyeing properties of some novel azo disperse dyes based on naphthalimides.

    Science.gov (United States)

    Shaki, Hanieh; Gharanjig, Kamaladin; Khosravi, Alireza

    2015-01-01

    A series of novel disperse dyes containing azo group were synthesized through a diazotization and coupling process. The 4-amino-N-2-aminomethylpyridine-1,8-naphthalimide was diazotized by nitrosylsulphuric acid and coupled with various aromatic amines such as N,N-diethylaniline, N,N-dihydroxyethylaniline, 8-hydroxyquinoline, and 2-methylindole. Chemical structures of the synthesized dyes were characterized by Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), proton nuclear magnetic resonance ((1) H NMR), carbon nuclear magnetic resonance ((13) C NMR), elemental analysis, and ultraviolet-visible (UV-visible) spectroscopy. The spectrophotometric data of all dyes were evaluated in various solvents with different polarity. Eventually, the dyes were applied on polyamide fabrics in order to investigate their dyeing properties. The fastness properties of the dyed fabrics such as wash, light, and rubbing fastness degrees were measured by standard methods. Moreover, the color gamut of the synthesized dyes was measured on polyamide fabrics. Results indicated that some of the synthesized dyes were able to dye polyamide fabrics with deep shades. They had very good wash and rubbing fastness degrees and moderate-to-good light fastness on polyamide fabrics. The antibacterial and antifungal activities of the synthesized dyes were evaluated in soluble state and on the dyed fabrics. The results indicated that dye 2 containing N,N-dihydroxyethylaniline as coupler had the highest activity against all the bacteria and fungi used. © 2015 American Institute of Chemical Engineers.

  3. The influence of the addition of dye surface modifier on the performance of transparent dye sensitized solar cells

    Science.gov (United States)

    Rosa, Erlyta Septa; Shobih, Retnaningsih, Lilis; Muliani, Lia; Hidayat, Jojo

    2017-11-01

    The light-harvesting properties and charge injection kinetics of dye molecules play a significant role to improve the performance of dye-sensitized solar cells (DSSC). Dyes based on metal complexes with ruthenium complexes also a variety of metal-organic dyes such as Zn-porphyrin derivatives have been used. The requirements for dye to function as a photosensitizer in DSSC are the absorption in the visible or near-infrared regions of the solar spectrum and the binding to the semiconductor TiO2. In order to interact with the TiO2 surface it is preferable that the dye has a functional group as anchoring group such as carboxylic or other peripheral acidic. The carboxylic group is the most frequently used anchoring group, as in ruthenium-complex based dyes. However, carboxylic acid as an anchoring group is still not enough for conducting in electron injection to TiO2. In this research, 0.87 mg phosphonic acid is added to N719 and Z907 ruthenium-complex based dyes, rspectively, as a surface modifier to strengthen the anchoring group. The addition of dyes surface modifier on the transparent DSSC device performance is investigated. Under illumination of 500 Wm-2, the power conversion efficiency (PCE) of DSSC using N719 ruthenium increases from 2.09 % to 3.22 % by the addition of surface modifier. However, different results are obtained on Z907 dye, where efficiency decreases from 2.02 % to 1.58 %.

  4. Dye-Sensitized Approaches to Photovoltaics

    Science.gov (United States)

    Grätzel, Michael

    2008-03-01

    Sensitization of wide band-gap semiconductors to photons of energy less than the band-gap is a key step in two technically important processes - panchromatic photography and photoelectrochemical solar cells. In both cases the photosensitive species is not the semiconductor - silver halide or metal oxide - but rather an electrochemically active dye. The gap between the highest occupied molecular level (HOMO) and the lowest unoccupied molecular level (LUMO) is less than the band-gap of the semiconductor with which it is associated. It can therefore absorb light of a wavelength longer than that to which the semiconductor itself is sensitive. The electrochemical process is initiated when the dye molecule relaxes from its photoexcited level by electron injection into the semiconductor, which therefore acts as a photoanode. If the dye is in contact with a redox electrolyte, the negative charge represented by the lost electron can be recovered from the reduced state of the redox system, which in return is regenerated by charge transfer from a cathode. An external load completes the electrical circuit. The system therefore represents a conversion of the energy of absorbed photons into an electrical current by a regenerative device in every functional respect analogous to a solid-state photovoltaic cell. As in any engineering system, choice of materials, their optimization and their synergy are essential to efficient operation. While a semiconductor-electrolyte contact is analogous to a Schottky contact, in that a barrier is established between two materials of different conduction mechanism, with the possibility of optical absorption, charge carrier pair generation and separation, it should be remembered that the photogenerated valence band hole in the semiconductor represents a powerful oxidizing agent. Given that the band-gap is related to the strength and therefore the stability of chemical bonding within the semiconductor, for narrow-gap materials the most likely

  5. Parametric Optimization of Dye-Sensitized Solar Cells Using Far red Sensitizing Dye with Cobalt Electrolyte

    Science.gov (United States)

    Pradhan, A.; Saikiran, M.; Kapil, G.; Pandey, S. S.; Hayase, S.

    2017-11-01

    A far-red sensitizing dye SQ-75 has been employed as a model sensitizer with Co(bpy)2+/3+ redox electrolytes to fabricate dye-sensitized solar cells (DSSCs) and optimize the various device parameters which influence the overall photoconversion efficiency (PCE). It has been found that the optimization of the TiO2 thickness, surface treatment with TiCl4, and an optimum amount of the chenodeoxycholic acid (CDCA) as coadsorber are necessary to attain the overall improved PCE. TiCl4 surface treatment on both FTO and TiO2 has been found to outperform as compared to their untreated counterparts owing to the suppression of the charge recombination. DSSCs with an optimized TiO2 thickness of 6 μm and CDCA concentration of 4 mM have exhibited best performance due to enhanced photon harvesting and reduced dye aggregation, respectively.

  6. Triple dye plus rubbing alcohol versus triple dye alone for umbilical cord care.

    Science.gov (United States)

    Suliman, Alawia K; Watts, Heidi; Beiler, Jessica; King, Tonya S; Khan, Sana; Carnuccio, Marybeth; Paul, Ian M

    2010-01-01

    Current practices for umbilical cord care vary across centers, but the evidence regarding these practices and their impact on cord separation, complications, and health care use are limited. The objective of this study was to compare the effect of triple dye alone (brilliant green, crystal violet, and proflavine hemisulfate) versus triple dye plus rubbing alcohol (isopropyl alcohol) twice daily on time to umbilical cord separation, complications, and health care use. For the 90 newborns who completed the study, there were no significant differences between treatment groups for time to cord separation, cord-related morbidities, or cord-related urgent care. Based on these study results, there does not appear to be significant benefit to the addition of twice daily applications of rubbing alcohol to neonatal umbilical cords following triple dye treatment after birth.

  7. FATE OF WATER SOLUBLE AZO DYES IN THE ACTIVATED SLUDGE PROCESS

    Science.gov (United States)

    The objective of this study was to determine the partitioning of water soluble azo dyes in the activated sludge process (ASP). Azo dyes are of concern because some of the dyes, dye precursors , and/or their degradation products such as aromatic amines (which are also dye precurso...

  8. Preparation of 6-hydroxyindolines and their use for preparation of novel laser dyes

    Science.gov (United States)

    Field, G.F.; Hammond, P.R.

    1993-10-26

    A novel method is described for the synthesis of 6-hydroxyindolines and new fluorescent dyes produced therefrom, which dyes are ring-constrained indoline-based rhodamine class dyes. These dyes have absorption and emission spectra which make them particularly useful in certain dye laser applications.

  9. The Effect of Two African Mineral Dyes on the Activity of Alkaline ...

    African Journals Online (AJOL)

    DR. MIKE HORSFALL

    The use of hair dye is fast gaining popularity especially among ladies and old men. Young ladies engage in the use of dyes mainly for fashion while old men use dyes to mask their grey hair. Dyes are basically of two types namely natural dyes and synthetic .... organic and inorganic components in the samples. The colour ...

  10. Biosynthesis of gold nanoparticles by Trichoderma sp. WL-Go for azo dyes decolorization.

    Science.gov (United States)

    Qu, Yuanyuan; Shen, Wenli; Pei, Xiaofang; Ma, Fang; You, Shengnan; Li, Shuzhen; Wang, Jingwei; Zhou, Jiti

    2017-06-01

    Developing an eco-friendly approach for metallic nanoparticles synthesis is important in current nanotechnology research. In this study, green synthesis of gold nanoparticles (AuNPs) was carried out by a newly isolated strain Trichoderma sp. WL-Go. UV-vis spectra of AuNPs showed a surface plasmon resonance peak at 550nm, and transmission electron microscopy images revealed that the AuNPs were of varied shape with well dispersibility. The optimal conditions for AuNPs synthesis were HAuCl4 1.0mmol/L, biomass 0.5g and pH7-11. Moreover, the bio-AuNPs could efficiently catalyze the decolorization of various azo dyes. This research provided a new microbial resource candidate for green synthesis of AuNPs and demonstrated the potential application of bio-AuNPs for azo dye decolorization. Copyright © 2016. Published by Elsevier B.V.

  11. Refractometric monitoring of dissolution and fluid flow with distributed feedback dye laser sensor

    DEFF Research Database (Denmark)

    Vannahme, Christoph; Sørensen, Kristian Tølbøl; Gade, Carsten

    2015-01-01

    and fast fluid flow with DFB dye laser sensors with an optical imaging spectroscopy setup is presented. The dye laser sensors provide both low detection limits and high spatial resolution. It is demonstrated how the materials NaCl, sucrose, and bovine serum albumin show characteristic dissolution patterns......Monitoring the dissolution of solid material in liquids and monitoring of fluid flow is of significant interest for applications in chemistry, food production, medicine, and especially in the fields of microfluidics and lab on a chip. Here, real-time refractometric monitoring of dissolution....... The unique feature of the presented method is a high frame rate of up to 20 Hz, which is proven to enable the monitoring of fast flow of a sucrose solution jet into pure water. (C) 2015 Optical Society of America...

  12. Synthesis and characterisation of highly fluorescent core-shell nanoparticles based on Alexa dyes

    Energy Technology Data Exchange (ETDEWEB)

    Natte, Kishore; Behnke, Thomas; Orts-Gil, Guillermo, E-mail: guillermo.orts-gil@bam.de; Wuerth, Christian; Friedrich, Joerg F.; Oesterle, Werner; Resch-Genger, Ute, E-mail: ute.resch@bam.de [BAM Federal Institute for Materials Research and Testing (Germany)

    2012-02-15

    Current and future developments in the emerging field of nanobiotechnology are closely linked to the rational design of novel fluorescent nanomaterials, e.g. for biosensing and imaging applications. Here, the synthesis of bright near infrared (NIR)-emissive nanoparticles based on the grafting of silica nanoparticles (SNPs) with 3-aminopropyl triethoxysilane (APTES) followed by covalent attachment of Alexa dyes and their subsequent shielding by an additional silica shell are presented. These nanoparticles were investigated by dynamic light scattering (DLS), transmission electron microscopy (TEM) and fluorescence spectroscopy. TEM studies revealed the monodispersity of the initially prepared and fluorophore-labelled silica particles and the subsequent formation of raspberry-like structures after addition of a silica precursor. Measurements of absolute fluorescence quantum yields of these scattering particle suspensions with an integrating sphere setup demonstrated the influence of dye labelling density-dependent fluorophore aggregation on the signaling behaviour of such nanoparticles.

  13. Refractometric monitoring of dissolution and fluid flow with distributed feedback dye laser sensor.

    Science.gov (United States)

    Vannahme, Christoph; Sørensen, Kristian Tølbøl; Gade, Carsten; Dufva, Martin; Kristensen, Anders

    2015-03-09

    Monitoring the dissolution of solid material in liquids and monitoring of fluid flow is of significant interest for applications in chemistry, food production, medicine, and especially in the fields of microfluidics and lab on a chip. Here, real-time refractometric monitoring of dissolution and fast fluid flow with DFB dye laser sensors with an optical imaging spectroscopy setup is presented. The dye laser sensors provide both low detection limits and high spatial resolution. It is demonstrated how the materials NaCl, sucrose, and bovine serum albumin show characteristic dissolution patterns. The unique feature of the presented method is a high frame rate of up to 20 Hz, which is proven to enable the monitoring of fast flow of a sucrose solution jet into pure water.

  14. Optical properties of cyanine dyes in nanotubes of chrysotile asbestos

    Science.gov (United States)

    Starovoytov, Anton A.; Vartanyan, Tigran A.; Belotitskii, Vladimir I.; Kumzerov, Yuri A.; Sysoeva, Anna A.

    2017-08-01

    Optical properties of cyanine dye molecules incorporated in nanotubes of natural chrysotile asbestos are studied. The absorption and fluorescence spectra of dye in asbestos have the similar shapes as in the ethanol solution, apart from small blue shift of the maxima. The Stokes shift in asbestos is smaller than in the ethanol solution. The fluorescence decay times of the dyes in asbestos nanotubes are found to be larger than that in the case of thin films of the same dyes formed on the transparent dielectric supports. This observation is rationalized in terms of the stereoisomerization hindrance in the excited electronic state of dye molecules. At the same time linear dichroism and fluorescence anisotropy observed in the experiment indicate that the embedded dye molecules are well-isolated monomer oriented predominantly along asbestos nanotubes.

  15. Biosorption of Azo dyes by spent Rhizopus arrhizus biomass

    Science.gov (United States)

    Salvi, Neeta A.; Chattopadhyay, S.

    2017-10-01

    In the present study, spent Rhizopus arrhizus biomass was used for the removal of six azo dyes from aqueous solutions. The dye removal capacity of the biomass was evaluated by conducting batch tests as a function of contact time, biomass dosage, pH and initial dye concentrations. The pseudo-second-order kinetic model fitted well with the experimental data with correlation coefficients greater than 0.999, suggesting that chemisorptions might be the rate limiting step. The equilibrium sorption data showed good fit to the Langmuir isotherm model. Among the six dyes tested, the maximum monolayer adsorption capacity for fast red A and metanil yellow was found to be 108.8 and 128.5 mg/g, respectively. These encouraging results suggest that dead Rhizopus arrhizus biomass could be a potential biomaterial for the removal of azo dyes from aqueous dye solution.

  16. Co-sensitization of organic dyes for efficient dye-sensitized solar cells.

    Science.gov (United States)

    Cheng, Ming; Yang, Xichuan; Li, Jiajia; Zhang, Fuguo; Sun, Licheng

    2013-01-01

    Novel cyanine dyes, in which a tetrahydroquinoline derivative is used as an electron donor and 1-butyl-5-carboxy-3, 3-dimethyl-indol-1-ium moiety is used as an electron acceptor and anchoring group, were designed and synthesized for application in dye-sensitized solar cells. The photovoltaic performance of these solar cells depends markedly on the molecular structure of the dyes in terms of the n-hexyl chains and the methoxyl unit. Retardation of charge recombination caused by the introduction of n-hexyl chains resulted in an increase in electron lifetime. As a consequence, an improvement of open-circuit photovoltage (V(oc)) was achieved. Also, the electron injection efficiencies were improved by the introduction of methoxyl moiety, which led to a higher short-circuit photocurrent density (J(sc)). The highest average efficiency of the sensitized devices (η) was 5.6% (J(sc)=13.3 mA cm(-2), V(oc)=606 mV, and fill factor FF=69.1%) under 100 mW cm(-2) (AM 1.5G) solar irradiation. All of these dyes have very high absorption extinction coefficients and strong absorption in a relatively narrow spectrum range (500-650 nm), so one of our organic dyes was explored as a sensitizer in co-sensitized solar cells in combination with the other two other existing organic dyes. Interestingly, a considerably improved photovoltaic performance of 8.2% (J(sc)=20.1 mA cm(-2), V(oc)=597 mV, and FF=68.3%) was achieved and the device showed a panchromatic response with a high incident photon-to-current conversion efficiency exceeding 85% in the range of 400-700 nm. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Panchromatic Response in Solid-State Dye-Sensitized Solar Cells Containing Phosphorescent Energy Relay Dyes

    KAUST Repository

    Yum, Jun-Ho

    2009-11-23

    Running relay: Incorporating an energyrelay dye (ERD) into the hole transporter of a dye-sensitized solar cell increased power-conversion efficiency by 29% by extending light harvesting into the blue region. In the operating mechanism (see picture), absorption of red photons by the sensitizer transfers an electron into TiO2 and a hole into the electrolyte. Blue photons absorbed by the ERD are transferred by FRET to the sensitizer. Chemical Equitation Presentation © 2009 Wiley-VCH Verlag GmbH & Co. KGaA.

  18. Dye sensitized photovoltaic cells: Attaching conjugated polymers to zwitterionic ruthenium dyes

    DEFF Research Database (Denmark)

    Krebs, Frederik C; Biancardo, M.

    2006-01-01

    The synthesis of a zwitterionic ruthenium dye that binds to anatase surfaces and has a built-in functionality that allows for the attachment of a conjugated polymer chain is presented. The system was found to adsorb on the surface of anatase anchored by the ruthenium dye. Two types of devices were...... and the complex was adsorbed onto the surface before evaporation of gold electrodes. Alternative devices were obtained by spincoating of the polymer solution onto PEDOT:PSS covered indium-doped tin oxide substrates. PEC solar cells gave the best results and the main finding was that the polymer chain served...

  19. Synthesis of dye linked conducting block copolymers, dye linked conducting homopolymers and preliminary application to photovoltaics

    DEFF Research Database (Denmark)

    Krebs, Frederik C; Hagemann, O.; Jørgensen, M.

    2004-01-01

    A synthetic approach to the synthesis of a large super molecule composed of two chemically different conducting polymer blocks with, respectively, high and low lying electronic energy levels linked through a porphyrin dye molecule is presented. The synthetic strategies to these molecular architec......A synthetic approach to the synthesis of a large super molecule composed of two chemically different conducting polymer blocks with, respectively, high and low lying electronic energy levels linked through a porphyrin dye molecule is presented. The synthetic strategies to these molecular...

  20. A New Generation of Glycoconjugated Azo Dyes Based on Aminosugars

    OpenAIRE

    Guazzelli, Lorenzo; Catelani, Giorgio; D’Andrea, Felicia

    2015-01-01

    The third generation of glycoconjugated azo dyes (GADs) was prepared linking monoazo dyes to 6-amino-6-deoxy-d-galactose or 6′amino-6′-deoxylactose through mixed amido-ester connections. The complementary conjugation reactions were studied using the succinyl derivative of either the acetal protected aminosugar or the azo dye. Target “naturalized” GADs were obtained after acid hydrolysis of the acetal protecting groups present on the sugar moiety.

  1. A New Generation of Glycoconjugated Azo Dyes Based on Aminosugars

    Directory of Open Access Journals (Sweden)

    Lorenzo Guazzelli

    2015-01-01

    Full Text Available The third generation of glycoconjugated azo dyes (GADs was prepared linking monoazo dyes to 6-amino-6-deoxy-d-galactose or 6′amino-6′-deoxylactose through mixed amido-ester connections. The complementary conjugation reactions were studied using the succinyl derivative of either the acetal protected aminosugar or the azo dye. Target “naturalized” GADs were obtained after acid hydrolysis of the acetal protecting groups present on the sugar moiety.

  2. Adsorption Properties of Lac Dyes on Wool, Silk, and Nylon

    Directory of Open Access Journals (Sweden)

    Bo Wei

    2013-01-01

    Full Text Available There has been growing interest in the dyeing of textiles with natural dyes. The research about the adsorption properties of natural dyes can help to understand their adsorption mechanism and to control their dyeing process. This study is concerned with the kinetics and isotherms of adsorption of lac dyes on wool, silk, and nylon fibers. It was found that the adsorption kinetics of lac dyes on the three fibers followed the pseudosecond-order kinetic model, and the adsorption rate of lac dyes was the fastest for silk and the slowest for wool. The activation energies for the adsorption process on wool, silk, and nylon were found to be 107.15, 87.85, and 45.31 kJ/mol, respectively. The adsorption of lac dyes on the three fibers followed the Langmuir mechanism, indicating that the electrostatic interactions between lac dyes and those fibers occurred. The saturation values for lac adsorption on the three fibers decreased in the order of wool > silk > nylon; the Langmuir affinity constant of lac adsorption on nylon was much higher than those on wool and silk.

  3. UV protection property of cloths dyed with flavonoid plant dye

    OpenAIRE

    小林, 優子; 鈴木, 恒夫

    2011-01-01

    The aging of skin and pigmentation are caused by the ultraviolet radiation (UV). It is important for UV protection of clothes to protection of human body. Materials, dyes and tissue textiles were the factors that affect UV protection of clothes. Among them, dyes were paid attention and vegetable dyes were used in this experiment. Plant pigment in a cell was an essential material of growth and sustaining life. And it was related with sun light. This study was examined about the dyeing with oni...

  4. Phase change material for efficient removal of crystal violet dye.

    Science.gov (United States)

    Haik, Yousef; Qadri, Shahnaz; Ganoe, Ashley; Ashraf, Sarmadia; Sawafta, Reyad

    2010-04-15

    Hazardous dye removal and recovery from wastewater requires efficient capturing material. We report a phase change material (PCM) with phase change temperature of 16 degrees C giving up to 98% removal of crystal violet in few minutes. The PCM was found to collect 54 times of its weight soluble dye. The dye adsorption kinetics obeys a second order pseudo rate. Upon cooling the PCM to below 16 degrees C it gels and enabled solid removal of the captured dye. 2009 Elsevier B.V. All rights reserved.

  5. Removal of synthetic food dyes in aqueous solution by Octolig.

    Science.gov (United States)

    Martin, Dean F; Alessio, Rachael J; McCane, Cheryl H

    2013-01-01

    We studied six of the seven food dyes commonly used, e.g., FD&C Blue No. 1 and No. 2, Green No. 3, Red No. 3 and No. 40, Yellow No. 5 and No. 6. Quantitative removal was achieved by passage of dyes in aqueous solutions over chromatography columns packed with Octolig, a polyethylenediimine covalently attached to high-surface-area silica. A structural feature most of the dyes have in common are the presence of sulfonate groups attached to aromatic molecules. Prior studies and the current one indicated that the seventh food dye (Green No. 3) should also be quantitatively removed. Matrix effects were considered, but none were observed.

  6. Disperse dyeing properties of (easy dyeable polyester)/spandex blend

    Science.gov (United States)

    Rahman, M. M.; Mamun Kabir, S. M.; Kim, H.; Koh, J.

    2017-10-01

    Using a low and a high energy disperse dye, several dyeing properties, like colour depth, partition ratio, degree of dye exhaustion, build–up and fastness properties of (easy dyeable polyester)/spandex blend were thoroughly investigated. Various dyeing temperatures ranging from 90°C to 130°C were applied. To check its performance, the conventional (regular polyester/spandex) blend was also dyed. (easy dyeable polyester)/spandex blend showed higher dyeability on PET and lower staining on spandex at low temperature compared to (regular polyester)/spandex blend..

  7. Solid state microcavity dye lasers fabricated by nanoimprint lithography

    DEFF Research Database (Denmark)

    Nilsson, Daniel; Nielsen, Theodor; Kristensen, Anders

    2004-01-01

    We present a solid state polymer microcavity dye laser, fabricated by thermal nanoimprint lithography (NIL) in a dye-doped thermoplast. The thermoplast poly-methylmethacrylate (PMMA) is used due to its high transparency in the visible range and its robustness to laser radiation. The laser dye...... propagating TE–TM modes. The laser cavity has the lateral shape of a trapezoid, supporting lasing modes by reflection on the vertical cavity walls. The solid polymer dye lasers emit laterally through one of the vertical cavity walls, when pumped optically through the top surface by means of a frequency...

  8. Cosensitization with Vat-Based Organic Dyes for Enhanced Spectral Response of Dye-Sensitized Solar Cells

    Science.gov (United States)

    Hosseinnezhad, Mozhgan

    2017-04-01

    Cosensitization using two organic dyes with supplementary absorption spectra on a photoelectrode is an effective method for improving the photovoltaic properties of dye-sensitized solar cells. Two organic dyes based on indigo and thioindigo have been synthesized, purified, and used to sensitize solar cells with spectral response extending across the entire visible region. To improve their photoelectric properties, different molar ratios were investigated, yielding total efficiency of 6.17% at dye 1:dye 2 = 4:6. The effect of the concentration of Cheno antiaggregation agent on the performance of the dye-sensitized solar cells was also considered. The results demonstrate that higher conversion efficiency ( η = 6.82%) was achieved with 10 × 10-3 M Cheno. Finally, the performance of cosensitized solar cells was measured at different temperatures between 10°C and 50°C. The results indicated that J sc decreased with increasing temperature, directly affecting the conversion efficiency.

  9. Effects of heat treatment on the dye adsorption of ZnO nanorods for dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Won Suk; Choi, Seok Cheol; Sohn, Sang Ho [Kyungpook National University, Daegu (Korea, Republic of); Oh, Sang Jin [Phoenix Materials, Gumi (Korea, Republic of)

    2012-11-15

    Well-aligned ZnO nanorods for the photoelectrode of dye-sensitized solar cells (DSSCs) were grown via a sonochemical method, and the heat-treatment effects on the dye adsorption in the DSSCs were studied. The heat treatment of well-aligned ZnO nanorods was performed at 200 ∼ 500 .deg. C for 1 h, which was immediately followed by the dye adsorption. The dye amounts adsorbed in the ZnO nanorods were estimated from the UV-Vis absorbance by using Beer-Lambert's law. The efficiency of the DSSCs with ZnO nanorods was measured to investigate the heat-treatment effects of ZnO nanorods on the dye adsorption properties. The heat-treatment of ZnO nanorods was found to yield a change in their dye adsorption ability, resulting in a change in the efficiency of the DSSCs.

  10. Effects of heat treatment on the dye adsorption of ZnO nanorods for dye-sensitized solar cells

    Science.gov (United States)

    Yun, Won Suk; Choi, Seok Cheol; Sohn, Sang Ho; Oh, Sang Jin

    2012-11-01

    Well-aligned ZnO nanorods for the photoelectrode of dye-sensitized solar cells (DSSCs) were grown via a sonochemical method, and the heat-treatment effects on the dye adsorption in the DSSCs were studied. The heat treatment of well-aligned ZnO nanorods was performed at 200 ˜ 500 °C for 1 h, which was immediately followed by the dye adsorption. The dye amounts adsorbed in the ZnO nanorods were estimated from the UV-Vis absorbance by using Beer-Lambert's law. The efficiency of the DSSCs with ZnO nanorods was measured to investigate the heat-treatment effects of ZnO nanorods on the dye adsorption properties. The heat-treatment of ZnO nanorods was found to yield a change in their dye adsorption ability, resulting in a change in the efficiency of the DSSCs.

  11. Natural dye extracted from karkadah and its application in dye-sensitized solar cells: experimental and density functional theory study.

    Science.gov (United States)

    Reda, S M; Soliman, K A

    2016-02-01

    This work presents an experimental and theoretical study of cyanidin natural dye as a sensitizer for ZnO dye-sensitized solar cells. ZnO nanoparticles were prepared using ammonia and oxalic acid as a capping agent. The calculated average size of the synthesized ZnO with different capping agents was found to be 32.1 nm. Electronic properties of cyanidin and delphinidin dye were studied using density functional theory (DFT) and time-dependent DFT with a B3LYP/6-31G(d,p) level. By comparing the theoretical results with the experimental data, the cyanidin dye can be used as a sensitizer in dye-sensitized solar cells. An efficiency of 0.006% under an AM-1.5 illumination at 100  mW/cm(2) was attained. The influence of dye adsorption time on the solar cell performance is discussed.

  12. A Note on the Dyeing of Wool Fabrics Using Natural Dyes Extracted from Rotten Wood-Inhabiting Fungi

    Directory of Open Access Journals (Sweden)

    Vicente A. Hernández

    2018-02-01

    Full Text Available Fungal isolates obtained from rotten wood samples were identified and selected by their ability to produce fungal dyes in liquid media. Fungal isolates produced natural extracellular dyes with colors ranging from red to orange, yellow and purple. Dyes from two of these fungi, Talaromyces australis (red and Penicillium murcianum (yellow, were extracted and used to dye wool samples in a Data Color Ahiba IR Pro-Trade (model Top Speed II machine. The protein nature of wool interacted well with the fungal dyes producing colors suitable for textile applications when used to a concentration of 0.1 g L−1. Results on color fastness when washing confirmed the affinity of the dyes with wool as the dyed samples kept their color in acceptable ranges after washing, without the implementation of mordanting pretreatments or the use of fixing agents.

  13. Inhibitory effect and mechanism of azo dyes on anaerobic methanogenic wastewater treatment: Can redox mediator remediate the inhibition?

    Science.gov (United States)

    Dai, Ruobin; Chen, Xiaoguang; Luo, Ying; Ma, Puyue; Ni, Shengsheng; Xiang, Xinyi; Li, Gang

    2016-11-01

    Inhibitory effect of azo dyes on anaerobic methanogenic wastewater treatment (AMWT) has been studied mainly focusing on biological toxicity in the batch test with simulated sole co-substrate. Detailed information on inhibitory effect and mechanism of azo dyes during the long-term operation with real complex co-substrate is limited. Moreover, whether redox mediator (RM) could remediate the inhibition is still unclear in previous studies, especially under the complex scenario. In this study, the real textile wastewater with alternative concentrations of azo dyes (0-600 mg/L) were used to operate a lab-scale high-rate anaerobic methanogenic bioreactor for 127 days, and 50 μM anthraquinone-2-sulfonate (AQS) as RM was added at the last period of operation. Azo dyes with concentration of 600 mg/L could cause significant inhibition on overall (decolorizing and methanogenic) performance of AMWT. Specific methanogenic activity assays showed that acetoclastic methanogens was more susceptible to high concentration azo dyes than hydrogenotrophic methanogens. The spatial distribution of extracellular polymeric substance in the anaerobic granular sludge (AGS) showed that the high biological toxicity of azo dyes was mainly attributed to enrichment effect in tightly bound-EPS (TB-EPS). The channels of AGS was clogged by azo dyes, which was evidenced by the hard release of aromatic amines in EPSs as well as decreased porosity of AGS and scanning electron microscope images. Meanwhile, the settling ability, particle size and strength of AGS all deteriorated after azo dyes concentration exceeded 450 mg/L. The dosing of AQS could mostly remediate overall performance of the bioreactor even if the recovery of acetoclastic methanogens was slow. However, except for the porosity with a part of recovery, physical characteristics of AGS hardly recovered, and washout of sludge from the bioreactor was still happening. It suggested that additional attention should be paid to prevent sludge

  14. Database of two-dimensional polyacrylamide gel electrophoresis of proteins labeled with CyDye DIGE Fluor saturation dye.

    Science.gov (United States)

    Fujii, Kazuyasu; Kondo, Tadashi; Yokoo, Hideki; Okano, Tetsuya; Yamada, Masayo; Yamada, Tesshi; Iwatsuki, Keiji; Hirohashi, Setsuo

    2006-03-01

    CyDye DIGE Fluor saturation dye (saturation dye, GE Healthcare Amersham Biosciences) enables highly sensitive 2-D PAGE. As the dye reacts with all reduced cysteine thiols, 2-D PAGE can be performed with a lower amount of protein, compared with CyDye DIGE Fluor minimal dye (GE Healthcare Amersham Biosciences), the sensitivity of which is equivalent to that of silver staining. We constructed a 2-D map of the saturation dye-labeled proteins of a liver cancer cell line (HepG2) and identified by MS 92 proteins corresponding to 123 protein spots. Functional classification revealed that the identified proteins had chaperone, protein binding, nucleotide binding, metal ion binding, isomerase activity, and motor activity. The functional distribution and the cysteine contents of the proteins were similar to those in the most comprehensive 2-D database of hepatoma cells (Seow et al.., Electrophoresis 2000, 21, 1787-1813), where silver staining was used for protein visualization. Hierarchical clustering on the basis of the quantitative expression profiles of the 123 characterized spots labeled with two charge- and mass-matched saturation dyes (Cy3 and Cy5) discriminated between nine hepatocellular carcinoma cell lines and primary cultured hepatocytes from five individuals, suggesting the utility of saturation dye and our database for proteomic studies of liver cancer.

  15. Theoretical study on the application of double-donor branched organic dyes in dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Yan-Hong; Liu, Rui-Rui [Gansu Key Laboratory of Polymer Materials, College of Chemistry and Chemical Engineering, Key Laboratory of Eco-environment-related Polymer Materials, Ministry of Education, Northwest Normal University, Lanzhou, 730070, Gansu (China); Zhu, Kai-Li [College of Chemistry and Life Science, Gansu Normal University for Nationalities, Hezuo, 747000, Gansu (China); Song, Yan-Lin [Gansu Key Laboratory of Polymer Materials, College of Chemistry and Chemical Engineering, Key Laboratory of Eco-environment-related Polymer Materials, Ministry of Education, Northwest Normal University, Lanzhou, 730070, Gansu (China); Geng, Zhi-Yuan, E-mail: zhiyuangeng@126.com [Gansu Key Laboratory of Polymer Materials, College of Chemistry and Chemical Engineering, Key Laboratory of Eco-environment-related Polymer Materials, Ministry of Education, Northwest Normal University, Lanzhou, 730070, Gansu (China)

    2016-09-15

    A novel organic dye with 2D-A structure has been designed and calculated whereby density functional theory (DFT) and time-dependent density functional theory (TD-DFT) for dye-sensitized solar cells. The double-donor branched dye which was consisted of two separated light-harvesting moieties was beneficial to photocurrent generation. First, we discussed the effects of different donor chains on photoelectric performance in the dye molecule, using the DTP-B8 which was a previously reported structure as the reference. Only to conclude that the suitable length can achieve the satisfactory efficiency. Secondly, to modify and sift potential sensitizers further, three series of dyes (BC-series, CB-series and CC-series) were designed and characterized. The increased molar extinction coefficient and the red-shifted λ{sub max} was attributed to an increasing in electron conjunction. This work presented a new route to design sensitizers that provide two channels for donating more electrons and improve the final efficiency. It is expected to provide some theoretical guidance on designing and synthetizing high efficiency photosensitive dye in the future experiments. - Highlights: • A novel organic dye with 2D-A structure was designed and characterized. • The double-donor branched dye was consisted of two separated light-harvesting paths. • The double-donor branched dye was beneficial to photocurrent generation. • The molar extinction coefficient was greatly improved in this novel structure. • Four promising candidates have been screened out.

  16. Synthesis, dyeing performance on polyester fiber and antimicrobial studies of some novel pyrazolotriazine and pyrazolyl pyrazolone azo dyes

    Directory of Open Access Journals (Sweden)

    Hala F. Rizk

    2017-05-01

    Full Text Available 5-Amino-4-heterylazo-3-phenyl-1H-pyrazoles (2a–d were diazotized and coupled with malononitrile to give pyrazoloazo malononitrile which by heating in glacial acetic acid gave novel pyrazolo[5,1-c][1,2,4]triazine dyes (3a–d. Also, some diazopyrazolyl pyrazolone dyes (4a–h were synthesized by diazotization of 2a–d and coupled with some pyrazolone derivatives. The structure of the synthesized dyes was determined by elemental analysis and spectral data. All the synthesized compounds were applied as disperse dyes and their dyeing performance on polyester fabric was studied. The fastness and colorimetric properties were measured. The results revealed that the monoazo dyes have good fastness and good to moderate affinity to polyester fabric than diazo dyes. In addition, the synthesized dyes were screened for their antimicrobial activities against Staphylococcus aureus, Pseudomonas aeruginosa (Gram positive, Bacillus subtitles, Escherichia coli (Gram negative and Candida albicans, Aspergillus niger (Fungi. The results revealed that most of the prepared dyes have high antibacterial activity.

  17. Biosorption and biodegradation of a sulfur dye in high-strength dyeing wastewater by Acidithiobacillus thiooxidans.

    Science.gov (United States)

    Nguyen, Thai Anh; Fu, Chun-Chieh; Juang, Ruey-Shin

    2016-11-01

    The ability of the bacterial strain Acidithiobacillus thiooxidans to remove sulfur blue 15 (SB15) dye from water samples was examined. This bacterium could not only oxidize sulfur compounds to sulfuric acid but also promote the attachment of the cells to the surface of sulfidic particles, therefore serving as an efficient biosorbent. The biosorption isotherms were better described by the Langmuir equation than by the Freundlich or Dubinin-Radushkevich equation. Also, the biosorption process followed the pseudo-second-order kinetics. At pH 8.3 and SB15 concentrations up to 2000 mg L(-1) in the biomass/mineral salt solution, the dye removal and decolorization were 87.5% and 91.4%, respectively, following the biosorption process. Biodegradation was proposed as a subsequent process for the remaining dye (250-350 mg L(-1)). A central composite design was used to analyze independent variables in the response surface methodology study. Under the optimal conditions (i.e., initial dye concentration of 300 mg L(-1), initial biomass concentration of 1.0 g L(-1), initial pH of 11.7, and yeast extract dose of 60 mg L(-1)), up to 50% of SB15 was removed after 4 days of biodegradation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Rhodanine dyes for dye-sensitized solar cells : spectroscopy, energy levels and photovoltaic performance.

    Science.gov (United States)

    Marinado, Tannia; Hagberg, Daniel P; Hedlund, Maria; Edvinsson, Tomas; Johansson, Erik M J; Boschloo, Gerrit; Rensmo, Håkan; Brinck, Tore; Sun, Licheng; Hagfeldt, Anders

    2009-01-07

    Three new sensitizers for photoelectrochemical solar cells were synthesized consisting of a triphenylamine donor, a rhodanine-3-acetic acid acceptor and a polyene connection. The conjugation length was systematically increased, which resulted in two effects: first, it led to a red-shift of the optical absorption of the dyes, resulting in an improved spectral overlap with the solar spectrum. Secondly, the oxidation potential decreased systematically. The excited state levels were, however, calculated to be nearly stationary. The experimental trends were in excellent agreement with density functional theory (DFT) computations. The photovoltaic performance of this set of dyes as sensitizers in mesoporous TiO2 solar cells was investigated using electrolytes containing the iodide/triiodide redox couple. The dye with the best absorption characteristics showed the poorest solar cell efficiency, due to losses by recombination of electrons in TiO2 with triiodide. Addition of 4-tert butylpyridine to the electrolyte led to a strongly reduced photocurrent for all dyes due to a reduced electron injection efficiency, caused by a 0.15 V negative shift of the TiO2 conduction band potential.

  19. Organic Dyes Containing Coplanar Dihexyl-Substituted Dithienosilole Groups for Efficient Dye-Sensitised Solar Cells

    Directory of Open Access Journals (Sweden)

    Ciaran Lyons

    2017-01-01

    Full Text Available A chromophore containing a coplanar dihexyl-substituted dithienosilole (CL1 synthesised for use in dye-sensitised solar cells displayed an energy conversion efficiency of 6.90% under AM 1.5 sunlight irradiation. The new sensitiser showed a similar fill factor and open-circuit voltage when compared with N719. Impedance measurements showed that, in the dark, the charge-transfer resistance of a cell using CL1 in the intermediate-frequency region was higher compared to N719 (69.8 versus 41.3 Ω. Under illumination at AM 1.5G-simulated conditions, the charge-transfer resistances were comparable, indicative of similar recombination rates by the oxidised form of the redox couple. The dye showed instability in ethanol solution, but excellent stability when attached to TiO2. Classical molecular dynamics indicated that interactions between ethanol and the dye are likely to reduce the stability of CL1 in solution form. Time-dependent density functional theory studies were performed to ascertain the absorption spectrum of the dye and assess the contribution of various transitions to optical excitation, which showed good agreement with experimental results.

  20. Difference gel electrophoresis (DIGE) using CyDye DIGE fluor minimal dyes.

    Science.gov (United States)

    Chakravarti, Bulbul; Gallagher, Sean R; Chakravarti, Deb N

    2005-02-01

    One- and two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (1- and 2-D SDS-PAGE) have been widely used for the separation and quantitative estimation of proteins. Following electrophoresis, the gels are stained appropriately to visualize the proteins. Difference gel electrophoresis (DIGE) is a new technique in which different protein samples, individually labeled with specific CyDyes, are combined together followed by electrophoresis and post electrophoretic co-detection and co-analysis on the same gel. CyDye DIGE fluor minimal dyes, which consist of three different CyDyes with different spectral characteristics, have been widely used for such purposes. The technique is highly sensitive with a wide dynamic range for detection of proteins and compatible with state-of-the-art protein identification techniques using mass spectrometry. Although DIGE is mainly used to compare differential expression of various protein samples using 2-D SDS-PAGE, 1-D DIGE also has important applications in quantitative proteomic studies.

  1. Decolorization of azo dyes by Geobacter metallireducens.

    Science.gov (United States)

    Liu, Guangfei; Zhou, Jiti; Chen, Congcong; Wang, Jing; Jin, Ruofei; Lv, Hong

    2013-09-01

    Geobacter metallireducens was found to be capable of decolorizing several azo dyes with different structures to various extents. Pyruvate, ethanol, acetate, propionate, and benzoate could support 66.3 ± 2.6-93.7 ± 2.1 % decolorization of 0.1 mM acid red 27 (AR27) in 40 h. The dependence of the specific decolorization rate on AR27 concentration (25 to 800 μM) followed Michaelis-Menten kinetics (K m = 186.9 ± 1.4 μΜ, V max = 0.65 ± 0.02 μmol mg protein(-1) h(-1)). Enhanced AR27 decolorization was observed with the increase of cell concentrations ranging from 7.5 to 45 mgL(-1). AR27 decolorization by G. metallireducens was retarded by the presence of goethite, which competed electrons with AR27 and was reduced to Fe(II). The addition of low concentrations of humic acid (1-100 mgL(-1)) or 2-hydroxy-1,4-naphthoquinone (0.5-50 μM) could improve the decolorization performance of G. metallireducens. High-performance liquid chromatography analysis suggested reductive pathway to be responsible for decolorization. This was the first study on azo dye decolorization by Geobacter strain and might improve our understanding of natural attenuation and bioremediation of environments polluted by azo dyes.

  2. Photoactive dye-enhanced tissue ablation for endoscopic laser prostatectomy.

    Science.gov (United States)

    Ahn, Minwoo; Hau, Nguyen Trung; Van Phuc, Nguyen; Oh, Junghwan; Kang, Hyun Wook

    2014-11-01

    Laser light has been widely used as a surgical tool to treat benign prostate hyperplasia (BPH) over 20 years. Recently, application of high laser power up to 200 W was often reported to swiftly remove a large amount of prostatic tissue. The purpose of this study was to validate the feasibility of photoactive dye injection to enhance light absorption and eventually to facilitate tissue vaporization with low laser power. Chicken breast tissue was selected as a target tissue due to minimal optical absorption at the visible wavelength. Four biocompatible photoactive dyes, including amaranth (AR), black dye (BD), hemoglobin powder (HP), and endoscopic marker (EM), were selected and tested in vitro with a customized 532 nm laser system with radiant exposure ranging from 0.9 to 3.9 J/cm(2) . Light absorbance and ablation threshold were measured with UV-Vis spectrometer and Probit analysis, respectively, and compared to feature the function of the injected dyes. Ablation performance with dye-injection was evaluated in light of radiant exposure, dye concentration, and number of injection. Higher light absorption by injected dyes led to lower ablation threshold as well as more efficient tissue removal in the order of AR, BD, HP, and EM. Regardless of the injected dyes, ablation efficiency principally increased with radiant exposure, dye concentration, and number of injection. Among the dyes, AR created the highest ablation rate of 44.2 ± 0.2 µm/pulse due to higher absorbance and lower ablation threshold. High aspect ratios up to 7.1 ± 0.4 entailed saturation behavior in the tissue ablation injected with AR and BD, possibly resulting from plume shielding and increased scattering due to coagulation. Preliminary tests on canine prostate with a hydraulic injection system demonstrated that 80 W with dye injection yielded comparable ablation efficiency to 120 W with no injection, indicating 33% reduced laser power with almost equivalent performance. Due to

  3. Assessment of different dyes used in leakage studies.

    Science.gov (United States)

    Mente, Johannes; Ferk, Stephan; Dreyhaupt, Jens; Deckert, Andreas; Legner, Milos; Staehle, Hans Joerg

    2010-06-01

    The goal of this in vitro study was to identify the most suitable dye for endodontic dye leakage studies, which could be a further step towards standardisation. The root canals of 70 extracted, single-rooted human adult teeth were enlarged to apical size 50 using hand instruments. The teeth were divided into seven groups (n = 10 each), and all root canals were completely filled by injection with one of the following dyes: methylene blue 0.5% and 5%, blue ink, black ink, eosin 5%, basic fuchsin 0.5% and drawing ink. Transverse root sections from the coronal, middle and apical part of the roots were examined, and the percentage of the dentine penetrated by dye was evaluated by software-supported light microscopy. In addition, the range of particle size of drawing ink particles was evaluated. There were conspicuous differences in the relative dye penetration into the root dentine and the penetration behaviour in the different root sections (two-way ANOVA, both p < 0.0001). One dye (drawing ink) penetrated less into the root dentine compared with all the others (p <0.0001). The particle size of this agent (0.1-2 microm) corresponds best with the size range of a representative selection of 21 species of pathogenic endodontic bacteria. Compared to the other dyes tested, drawing ink appears to be superior for use in endodontic dye leakage studies. The penetration behaviour into the root dentine of all the other dyes tested might be one factor that limits the applicability of these dyes in dye leakage studies.

  4. Textile dye degradation using nano zero valent iron: A review.

    Science.gov (United States)

    Raman, Chandra Devi; Kanmani, S

    2016-07-15

    Water soluble unfixed dyes and inorganic salts are the major pollutants in textile dyeing industry wastewater. Existing treatment methods fail to degrade textile dyes and have limitations too. The inadequate treatment of textile dyeing wastewater is a major concern when effluent is directly discharged into the nearby environment. Long term disposal threatens the environment, which needs reclamation. This article reviews the current knowledge of nano zero valent iron (nZVI) technique in the degradation of textile dyes. The application of nZVI on textile dye degradation is receiving great attention in the recent years because nZVI particles are highly reactive towards the pollutant, less toxic, and economical. The nZVI particles aggregate quickly with respect to time and the addition of supports such as resin, nickel, zinc, bentonite, biopolymer, kaolin, rectorite, nickel-montmorillonite, bamboo, cellulose, biochar, graphene, and clinoptilolite enhanced the stability of iron nanoparticles. Inclusion of supports may in turn introduce additional toxic pollutants, hence green supports are recommended. The majority of investigations concluded dye color removal as textile dye compound removal, which is not factual. Very few studies monitored the removal of total organic carbon and observed the products formed. The results revealed that partial mineralization of the textile dye compound was achieved. Instead of stand alone technique, nZVI can be integrated with other suitable technique to achieve complete degradation of textile dye and also to treat multiple pollutants in the real textile dyeing wastewater. It is highly recommended to perform more bench-scale and pilot-scale studies to apply this technique to the textile effluent contaminated sites. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Daylight-driven photocatalytic degradation of ionic dyes with negatively surface-charged In2S3 nanoflowers: dye charge-dependent roles of reactive species

    Science.gov (United States)

    Ge, Suxiang; Cai, Lejuan; Li, Dapeng; Fa, Wenjun; Zhang, Yange; Zheng, Zhi

    2015-12-01

    Even though dye degradation is a successful application of semiconductor photocatalysis, the roles of reactive species in dye degradation have not received adequate attention. In this study, we systematically investigated the degradation of two cationic dyes (rhodamine B and methylene blue) and two anionic dyes (methyl orange and orange G) over negatively surface-charged In2S3 nanoflowers synthesized at 80 °C under indoor daylight lamp irradiation. It is notable to find In2S3 nanoflowers were more stable in anionic dyes degradation compared to that in cationic dyes removal. The active species trapping experiments indicated photogenerated electrons were mainly responsible for cationic dyes degradation, but holes were more important in anionic dyes degradation. A surface-charge-dependent role of reactive species in ionic dye degradation was proposed for revealing such interesting phenomenon. This study would provide a new insight for preparing highly efficient daylight-driven photocatalyst for ionic dyes degradation.

  6. Dye solar cell research: EU delegation presentation

    CSIR Research Space (South Africa)

    Cummings, F

    2009-11-09

    Full Text Available Franscious Cummings Energy and Processes Materials Science and Manufacturing Council for Scientific and Industrial Research P.O. Box 395 Pretoria 0001, South Africa 13 November 2009 © CSIR 2007 www.csir.co.za CONTENT head2right...Background head2rightCSIR Dye Solar Cell Research head2rightCollaborations and Links head2rightAcknowledgements © CSIR 2007 www.csir.co.za BACKGROUND head2rightSA is dry: Annual rainfall average of 450 mm compared with a world average...

  7. Resonance energy transfer: Dye to metal nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Wari, M. N.; Pujar, G. H.; Inamdar, S. R., E-mail: him-lax3@yahoo.com [Laser Spectroscopy Programme, Department of Physics, Karnatak University, Dharwad-580003 (India)

    2015-06-24

    In the present study, surface energy transfer (SET) from Coumarin 540A (C540 A) to Gold nanoparticle (Au) is demonstrated. The observed results show pronounced effect on the photoluminescence intensity and shortening of the lifetime of Coumarin 540A upon interaction with the spherical gold nanoparticle, also there are measured effects on radiative rate of the dye. Experimental results are analyzed with fluorescence resonance energy transfer (FRET) and SET theories. The results obtained from distance-dependent quenching provide experimental evidence that the efficiency curve slope and distance of quenching is best modeled by surface energy transfer process.

  8. Environment-responsive aza-BODIPY dyes quenching in water as potential probes to visualize the in vivo fate of lipid-based nanocarriers.

    Science.gov (United States)

    Hu, Xiongwei; Zhang, Jian; Yu, Zhou; Xie, Yunchang; He, Haisheng; Qi, Jianping; Dong, Xiaochun; Lu, Yi; Zhao, Weili; Wu, Wei

    2015-11-01

    Environment-responsive near-infrared (NIR) aza-BODIPY dyes capable of fluorescence quenching in water were explored to visualize the in vivo fate of model lipid-based nanocarriers, solid lipid nanoparticles (SLNs). The water-quenching effect of the dyes was confirmed to be sensitive and remained stable for at least 24h. In vitro lipolysis measured by fluorescence quenching completed within 20min, which was in correlation with alkaline compensation results. In vivo live imaging indicated predominant digestion of SLNs within 2h and complete digestion within 4h, which correlated well to in vitro data. Rekindling of quenched dyes by mixed micelles was observed in vitro, but not in vivo. In sharp contrast, SLNs encapsulating another NIR dye DiR showed persistent fluorescence both in vitro and in vivo despite significant lipolysis. It was envisaged that water-quenching fluorescence dyes can be used as probes to monitor the in vivo fate of lipid-based nanocarriers. Lipid-based drug delivery systems can provide an excellent nanocarrier platform for the delivery of poorly water-soluble drugs. Nonetheless, the mechanism of oral absorption and subsequent kinetics is poorly understood. In this article, the authors studied the novel use of near-infrared (NIR) aza-BODIPY dyes to visualize the fate of these lipid-based nanocarriers. The positive finding means that this approach may be useful for in-vivo monitoring of lipid-based nanocarriers. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. [Study on photocatalytic decomposition of azo-dyes by ZnO/carbon nanotubes composites by UV-Vis spectroscopy].

    Science.gov (United States)

    Xu, Jing; Song, Xiao-jie; Wei, Xian-wen

    2007-12-01

    ZnO/carbon nanotubes composites were prepared by hydrothermal treatment of the mixture of zinc nitrate and acid-treated multiwalled carbon nanotubes and characterized by transmission electron microscope (TEM) and X-ray powder diffraction (XRD). The TEM image indicated that ZnO nanoparticles with a diameter about 28 nm covered the carbon nanotubes. The XRD pattern shows that ZnO nanoparticles attached to the MWNTs exhibit a hexagonal phase. The diffraction peaks can be assigned to (100), (002), (101), (102), (110), (103), (200), (112) and (201) planes of the crystalline ZnO, respectively. The average size of the crystalline ZnO, calculated from the half-width of the (100) diffraction peak by the Scherrer equation, is 27.8 nm, which accords with the TEM observation. The ZnO/carbon nanotubes composites were used as a photocatalyst under sunlight for the decomposition of azo-dye, which was studied by UV-Vis spectroscopy. The effects of the illumination time, catalyst amount, initial dye concentration and the different structures of the dye on the photocatalytic process were investigated. It was noted that the intensity of the absorption peak corresponding to the azo-dye decreased rapidly at 400 nm during the photolysis process and the decomposition of azo-dye was a quasi-first order reaction. The decomposition rates for azo-dyes such as acid orange, Acid bright red, Acid light yellow are 0.09, 0.28 and 0.22 mg x L(-1) x min(-1), respectively, which maybe resulted from their different functional groups. It can be stated that the complete removal of color, after selection of optimum operation parameters, can be achieved in relatively short time by using ZnO/carbon nanotubes composites. After recycling 5 times, the catalyst still has more than 50% efficiency.

  10. Decolorization of irgalite dye by immobilized Pseuodomonas putida ...

    African Journals Online (AJOL)

    A carbon sorbent derived from an agriculture waste, mustard straw was applied to study the removal of irgalite dye from aqueous solution. Comparative study on adsorption and simultaneous adsorption and biodegradation (+) of irgalite dye using Pseuodomonas putida (MTCC 1194) with activated carbon prepared from ...

  11. utilisation of azo and triphenylmethane dyes as sole source of ...

    African Journals Online (AJOL)

    the treatment of dye wastewater. Key words: Bacillus sp, primary biodegradation, methyl orange, malachite green. INTRODUCTION. Synthetic dyes are extensively used in the textile, food, cosmetics, pharmaceutical, paper, leather, photographic and aquaculture industries (Schnick,. 1988; Chen et al., 1999). The main ...

  12. Synthesis and characterization of textile azo dyes derivatives of methoxyphenols

    OpenAIRE

    Ferreira, Isabel C.F.R.; Queiroz, Maria João R.P.

    1999-01-01

    Azo dyes are used extensively in the textile and dyestuff industries and effluents from these industrial processes are usually resistant to biological treatment. Textile azo dyes with bioaccessible groups such as guaiacol (2-methoxyphenol) and 2,6--dimethoxyphenol, for lignin-degrading fungus were synthesized using aminobenzoic and aminosulfonic acids as diazocomponents.

  13. Aerobic decolourization of two reactive azo dyes under varying ...

    African Journals Online (AJOL)

    Bacillus cereus isolated from dye industrial waste, that is, effluent and soil samples was screened for its ability to decolourize two reactive azo dye – cibacron black PSG and cibacron red P4B under aerobic conditions at pH 7 and incubated at 35°C over a five day period. Different carbon and nitrogen sources were used for ...

  14. Biodegradation of textile Azo Dyes by Phanerochaete chrysosporium

    OpenAIRE

    Ferreira, Isabel C.F.R.; Santos, Isabel M.; Queiroz, Maria João R.P.; Lima, Nelson

    1998-01-01

    Azo dyes are used extensively in the textile and dyestuff industries and effluents from these industrial processes are usually resistant to biological treatment. Textile azo dyes with bioaccessible groups such as guaiacol and 2,6-dimethoxyphenol, for lignin-degrading fungus as P. chrysosporium were synthesised.

  15. Types of Hair Dye and Their Mechanisms of Action

    Directory of Open Access Journals (Sweden)

    Simone Aparecida da França

    2015-04-01

    Full Text Available Hair color change by dye application is a common procedure among women. Hair dyes are classified, according to color resistance, into temporary, semipermanent, demipermanent and permanent. The first two are based on molecules which are already colored. Temporary dyes act through dye deposition on cuticles, but semipermanent may penetrate a little into the cortex and so the color resists up to six washes. Demipermanent and permanent dyes are based on color precursors, called oxidation dyes, and the final shade is developed by their interactions with an oxidizing agent, but they differ from the alkalizing agent used. In oxidation systems, there is an intense diffusion of the molecules into the cortex, what promotes a longer color resistance. Dyes and color precursors present differences related to chromophore groups, hair fiber affinity, water solubility, and photo stability. The aim of this review is to discuss the differences among hair dye products available in the market and their action mechanisms, molecular structures, application methods, and some aspects of formulations.

  16. Antimicrobial effect of natural dyes on some pathogenic bacteria ...

    African Journals Online (AJOL)

    P. granatum dye was most effective against the test bacteria except E. coli and S. epidermidis. The textile material impregnated with four natural dyes and maximum inhibition rates (respectivelly, 80, 86, 52%) were obtained against B. subtilis of wool samples dyed with P. granatum, A. cepa and R. tinctorum while maximum ...

  17. Biotransformation of Food Dyes by Human Intestinal Bacteria ...

    African Journals Online (AJOL)

    Biotransformation of food dyes (Tartrazine and Quinoline yellow) by Streptococcus faecalis and Escherichia coli isolated from human intestinal microflora was investigated. Decolourisation of the media containing the dyes was used as an index of biotransformation. Biotransformation was higher under aerobic than under ...

  18. Sensitization to reactive textile dyes in patients with contact dermatitis.

    Science.gov (United States)

    Manzini, B M; Motolese, A; Conti, A; Ferdani, G; Seidenari, S

    1996-03-01

    Reactive dyes are used especially for colouring natural fibres (cotton, silk and wool) that are widely used in Western countries, particularly Italy, in the production of clothes. The aim of our study was to investigate sensitization to the most commonly used reactive textile dyes in patients undergoing patch tests, and to assess the clinical relevance of contact sensitization to these dyes. 1813 consecutive patients underwent patch tests with the GIRDCA standard series and an additional textile series of 12 reactive dyes. 18 of these patients were sensitized to reactive dyes (0.99%) (4 only to reactive dyes). The dyes most frequently responsible for positive patch tests were Red Cibacron CR and Violet Remazol 5R (respectively, 8 and 5 positivities). In 5 cases only was a history of intolerance to particular garments given; of 4 patch tests performed with pieces of garment, 2 were positive. In 1 occupationally-exposed patient, airborne contact dermatitis was suspected. Owing to the lack of up-to-date patch test series, some cases of allergic contact dermatitis from textile dyes are probably misdiagnosed: new colouring agents are continuously introduced to the market, so that a close relationship with textile industry is necessary to improve our diagnostic tools.

  19. Textile dyes and pigments as a source of dioxins

    Energy Technology Data Exchange (ETDEWEB)

    Bostjan, K.; Marechal, A.M. le [Faculty of Mechanical Engineering, Maribor (Slovenia); Voncina, E. [Environmental Protection Institute, Maribor (Slovenia); Brodnjak-Voncina, D. [Faculty of Chemistry and Chemical Engineering, Maribor (Slovenia)

    2004-09-15

    Synthesis of colorants represents a relatively large group of chemicals with complex synthesis processes. Over 7 x 10 ton of dyestuff is produced annually worldwide with more than 100,000 types of dyes and pigments. During synthesis of some colorants polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) can be formed. Dioxins are related to halogens, especially chlorine and bromine homologues are most toxic and persistent. About 40% of worldwide used colorants contain organically bounded chlorine. Further formations of PCDD/Fs can occur via dyeing and textile finishing processes with conditions favoured for the generation of PCDD/Fs (high temperatures, alkaline conditions, UV radiations or other radical starters). Relative small number of data is available for PCDD/Fs presence and contents in textile dyes and pigments. Known sources of PCDD/Fs are dioxazine dyes and pigments, produced from chloranil1. Chloranil is produced from chlorinated phenols and during the synthesis PCDD/Fs as by products are formed. In a sample of Ni-phthalocyanine dye higher congeners of PCDD/Fs were found in {mu}g/kg concentration level. In our work six samples of disperse dyes were analysed for PCDD/Fs content. In two disperse black dyes, a mixture of anthraquinone and azo-disperse dye, considerable level ({mu}g/kg) of PCDD/Fs was determined. The OCDD was the dominant compound. Distribution of dioxins and their fate during textile processes were further investigated.

  20. Synthesis and application of dyes derived from Schaeffer's acid on ...

    African Journals Online (AJOL)

    The effects of increasing temperature of heat-set at 90 seconds, auxiliary concentration and dyeing time respectively were also investigated. Exhaustion dyeing method was used in all the investigations. The results showed that as the heat-set time increased percentage exhaustion decreased, indicating that the nylon 6,6 ...

  1. Decolourisation of chemically different dyes by enzymes from spent ...

    African Journals Online (AJOL)

    Based on the effect of hydrogen peroxide on the rate of decolourisation of each dye, the dyes could be divided into two groups. From the results of the present study, it could be concluded that the enzymes extracted from the spent compost of P. sajor-caju offers an economical advantage of obtaining industrially important ...

  2. Comparative studies on dyeing rate migration and wash fastness ...

    African Journals Online (AJOL)

    Migration and diffusion properties of synthesized azo dyes from 2-aminothiazole derivatives applied on commercial grade undyed cellulose acetate (CA) and cellulose triacetate (CTA) were investigated using dyeing conditions of 2% on weight of fabric (owf), 50:1 liquor ratio and subjected to ISO3 and ISO4 standard wash ...

  3. An Interdisciplinary Experiment: Azo-Dye Metabolism by "Staphylococcus Aureus"

    Science.gov (United States)

    Brocklesby, Kayleigh; Smith, Robert; Sharp, Duncan

    2012-01-01

    An interdisciplinary and engaging practical is detailed which offers great versatility in the study of a qualitative and quantitative metabolism of azo-dyes by "Staphylococcus aureus". This practical has broad scope for adaptation in the number and depth of variables to allow a focused practical experiment or small research project. Azo-dyes are…

  4. Suppression of cucurbit scab on cucumber leaves by photodynamic dyes

    Science.gov (United States)

    The goal of this study was to test the ability of the photodynamic dyes bengal rose, toluidine blue, and methylene blue, to protect systemically cucumber plants from cucurbit scab. At the stage of one true leaf, water or aqueous solutions of the dyes were applied to the leaf as droplets. When the se...

  5. Toxic textile dyes accumulate in wild European eel Anguilla anguilla.

    Science.gov (United States)

    Belpaire, Claude; Reyns, Tim; Geeraerts, Caroline; Van Loco, Joris

    2015-11-01

    Dyes are used to stain inks, paints, textile, paper, leather and household products. They are omnipresent, some are toxic and may threaten our environment, especially aquatic ecosystems. The presence of residues of sixteen dyes (triarylmethanes, xanthenes, phenothiazines and phenoxazines) and their metabolites was analyzed in muscle tissue samples of individual yellow-phased European eels (Anguilla anguilla) from 91 locations in Belgian rivers, canals and lakes sampled between 2000 and 2009 using ultra performance liquid chromatography-tandem mass spectrometry. Eel was contaminated by dyes in 77% of the sites. Malachite Green, Crystal Violet and Brilliant Green were present in 25-58% of the samples. Dye occurrence was related to the distribution of textile and dye production industries. This field study is the first large-scale survey to document the occurrence of artificial dyes in wildlife. Considering the annual amounts of dyes produced worldwide and the unintentional spillage during their use, our observations warrant additional research in other parts of the world. The presence of these highly toxic dyes in the European eel may form an additional threat to this critically endangered species. The contaminated eels should be considered as not suitable for consumption. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Electronic structure of Fe- vs. Ru-based dye molecules

    DEFF Research Database (Denmark)

    Johnson, Phillip S.; Cook, Peter L.; Zegkinoglou, Ioannis

    2013-01-01

    In order to explore whether Ru can be replaced by inexpensive Fe in dye molecules for solar cells, the differences in the electronic structure of Fe- and Ru-based dyes are investigated by X-ray absorption spectroscopy and first-principles calculations. Molecules with the metal in a sixfold...

  7. Photophysical and laser characteristics of pyrromethene 567 dye ...

    Indian Academy of Sciences (India)

    2015-11-27

    PM567) and rhodamine 6G (RH6G) dye was investigated using a home-made GIG- configured dye laser, excited by the second-harmonic radiation (at 532 nm) of a pulsed Nd:YAG laser. Higher laser efficiency was observed with ...

  8. The Chemistry of Vat Dyes. Palette of Color Monograph Series.

    Science.gov (United States)

    Epp, Dianne N.

    From prehistoric times people have been fascinated with color; from cave paintings to the latest computers, color has been a constant companion. Textiles are made more beautiful by the alteration or application of colorants. This teaching resource investigates vat dyes, a colorant class which includes the oldest dyes known as well as important…

  9. Characteristics and dyes biodegradation potential of crude lignolytic ...

    African Journals Online (AJOL)

    Characteristics and dyes biodegradation potential of crude lignolytic enzymes from white-rot fungus crepidotus variabilis isolated in coastal Tanzania. ... Also, they could remove up to 58% and 92% color from raw textile effluent and aromatic dyes, respectively, after 14 days of incubation at 30ºC and pH 4.5. Desalted and ...

  10. 40 CFR 721.4594 - Substituted azo metal complex dye.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted azo metal complex dye. 721... Substances § 721.4594 Substituted azo metal complex dye. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted azo metal complex...

  11. Structural and spectral properties of 4-phenoxyphthalonitrile dye ...

    Indian Academy of Sciences (India)

    Keywords. Electronic structure; absorption spectrum; dye sensitizer; density functional theory; vibrational spectra. 1. Introduction. The new technologies for direct solar energy conversion have gained more attention in the last few years. In parti- cular, Dye sensitized solar cells (DSSCs) are promising in terms of efficiency and ...

  12. Structural and spectral properties of 4-phenoxyphthalonitrile dye ...

    Indian Academy of Sciences (India)

    Structural and spectral properties of 4-phenoxyphthalonitrile dye sensitizer for solar cell applications ... electronic structures, polarizabilities and hyperpolarizabilities of organic dye sensitizer 4-phenoxyphthalonitrile was studied based on ab initio HF and density functional theory (DFT) using the hybrid functional B3LYP.

  13. Rose bengal-sensitized nanocrystalline ceria photoanode for dye ...

    Indian Academy of Sciences (India)

    Abstract. For efficient charge injection and transportation, wide bandgap nanostructured metal oxide semicon- ductors with dye adsorption surface and higher electron mobility are essential properties for photoanode in dye- sensitized solar cells (DSSCs). TiO2-based DSSCs are well established and so far have ...

  14. Removal of basic dyes from solution using coconut shell charcoal

    Directory of Open Access Journals (Sweden)

    Srisorrachatr Siriwan

    2017-01-01

    Full Text Available This research aims to use agricultural waste as an adsorbent for dye removal from textile wastewater. Coconut shell charcoal (CSC, an agricultural waste, was used as dye adsorbent whilst basic yellow13 (BY13 and basic red14 (BR14 were used as representative dye used in textile manufactory. The removal of BY13 and BR14 from aqueous solution by CSC was investigated in batch adsorption at room temperature. Two parameters investigated in this research were pH of dyes solution; pH 2, 7, and 11, and particle size of adsorbents; 510-700 μm and 1000-2000 μm. The adsorption model, Langmuir and Freundlich were also examined. It was found that by CSC, BY13 and BR14 had maximum removal percentage of 23.6 and 55.7 at pH 11. Size of adsorbent had also shown the effect on dye removal, i.e.; increasing size with decreasing removal capability. The dye removal experimental data were fitted to Langmuir adsorption model for both dyes with maximum adsorption capacity (qm for BY13 and BR14 of 19.76 and 22.93 mg/g, respectively. It can be implied that the adsorption is monolayer. It can conclude that CSC can be used as adsorbent for basic dye removal from aqueous solution.

  15. Rate equation simulation of temporal characteristics of a pulsed dye ...

    Indian Academy of Sciences (India)

    Laser & Plasma Technology Division, Bhabha Atomic Research Centre,. Mumbai 400 085, India ... To design and build high-power, pulsed dye laser MOPA systems, it is necessary to have a detailed knowledge .... qualitative and reasonably good quantitative agreement with experimental results on two separate dye laser ...

  16. Adsorption thermodynamics of some basic dyes uptake from ...

    African Journals Online (AJOL)

    The efficiency of Albizia lebbeck shell for the adsorption of auramine yellow (AY), basic malachite green (BMG) and basic violet (BV) dyes from aqueous solution has been studied in a batch system. The effects of contact time, adsorbent dosage, initial dye concentration, solution pH and temperature have been investigated ...

  17. BOXTO as a real-time thermal cycling reporter dye

    Indian Academy of Sciences (India)

    PRAKASH

    BOXTO as a real-time thermal cycling reporter dye. ASHRAF I AHMAD. Department of Chemical and Biological Engineering-Molecular Biotechnology, Chalmers University of Technology,. 405 30 Göteborg, Sweden. (Fax, 46 31 773 3910; Email, ashraf.ahmad@molbiotech.chalmers.se). The unsymmetrical cyanine dyes ...

  18. Orientation control of dye molecules in a liquid crystal.

    Science.gov (United States)

    Urisu, T; Kajiyama, K; Mizushima, Y

    1978-08-01

    Laser dye molecules (coumarin 6) were dissolved in a nematic liquid crystal MBBA + BBCA. Great changes in polarization and fluorescence vs applied voltage were found as well as a change in dielectric constant. Molecular orientation of the liquid crystal under the electric field and association of the dye molecules are identified as having the greatest effect on the fluorescence intensity.

  19. Fixed Drug Eruption due to Achiote Dye.

    Science.gov (United States)

    Tattersall, Ian; Reddy, Bobby Y

    2016-01-01

    Fixed drug eruption (FDE) is a localized type IV sensitivity reaction to a systemically introduced allergen. It usually occurs as a result of new medication, making identification and avoidance of the trigger medication straightforward; however, in a rare subset of cases no pharmacological source is identified. In such cases, the causative agent is often a food or food additive. In this report we describe a case of a FDE in a 12-year-old girl recently immigrated to the United States from Ecuador who had no medication exposure over the course of her illness. Through an exhaustive patient history and literature review, we were able to hypothesize that her presentation was caused by a dietary change of the natural achiote dye used in the preparation of yellow rice to a locally available commercial dye mix containing tartrazine, or Yellow 5, which has previously been implicated in both systemic hypersensitivity reactions and specifically in FDE. This report adds to the small body of available literature on non-pharmacological fixed hypersensitivity eruptions and illustrates an effective approach to the management of such a presentation when history is not immediately revealing.

  20. Adsorption of azo dyes on polymer materials

    Directory of Open Access Journals (Sweden)

    Panić Vesna V.

    2013-01-01

    Full Text Available The use of polymeric adsorbents for the removal of azo dyes from solution has been reviewed. Adsorption techniques are widely used to remove certain classes of pollutants from waters, especially those which are not easily biodegradable. The removal of azo dyes as pollutants from wastewaters of textile, paper, printing, leather, pharmaceutical and other industries has been addressed by the researchers. The wider use of already available adsorbents is restricted due to their high costs which lead to investigation and development of new materials that can be cheaper, eficient and easy regenerated. The aim of this article is to present to the readers the widespread investigations in recent years of synthetic and natural polymers as adsorbents and potential replacement of conventional adsorbents. This review presents only the data obtained using raw, hydrogel, grafted and crosslinked forms of synthetic and nature based polymers, and the discussion is limited to these polymer-based materials and their adsorption properties. [Projekat Ministarstva nauke Republike Srbije, br. 43009 i br. 172062.