Search results for "Dye"

Systematic study of SYBR green chromophore reveals major improvement with one heteroatom difference

2021

Five nucleic acid binding cyanine dyes were synthesized and their photophysical properties were evaluated. Changing a single heteroatom in the chromophore causes major differences both in brightness and photostability between the dyes. With such alteration, the brightness of the chromophore increased two-fold compared to the one found in SYBR Green I.

Ocher and cinnabar in the argaric funerary record

2012

The known cases of Bronze Age Argaric stained skeletons found in the Southeast of the Iberian Peninsula, have been analysed. The various hypotheses proposed relating to the origin of these colorations have been evaluated in light of new data provided by SEM, XRD and RAMAN spectroscopic analysis carried out on five Argaric graves of Murcia and Alicante. The results have indicated the presence of ochre and cinnabar on some of the skeletons. Without discarding the possibility that both substances were used in dyeing fabrics, it is proposed that their main use was for face and body make-up, being higher the number of recorded cases on female skeletons compared to male.

Benefits of a translucent building envelope made of DSC-integrated glass blocks

2015

The aim of this paper is to analyse the benefits deriving from the replacement of the glazed façades of an office building located in Palermo (Sicily) with a new translucent BIPV envelope made of multifunctional glass block panels integrated with Dye-sensitized Solar Cells (DSCs). The analysed 11-storey building is cladded by a curtain wall determining high management costs, especially during summer, in order to maintain indoor comfort. After the design of the building envelope and of the components for the connection of the glass block panels with existing load bearing structure, the energy performance of the building, before and after the replacement of its envelope, were analysed with th…

Cobalt Electrolyte/Dye Interactions in Dye-Sensitized Solar Cells: A Combined Computational and Experimental Study

2012

We report a combined experimental and computational investigation to understand the nature of the interactions between cobalt redox mediators and TiO2 surfaces sensitized by :ruthenium and organic dyes, and their impact on. the performance of the corresponding dye-sensitized solar cells (DSSCs). We : focus: on different ruthenium dyes and fully organic dyes, to understand the dramatic loss of efficiency observed for the prototype Ru(II) N719 dye in conjunction with :Cobalt: electrolytes. Both N719- and Z907-based DSSCs showed an increased lifetime in iodine-based electrolyte compared to the cobalt-based redox-shuttle; While the organic D21L6 and D25L6 cycles endowed.With long alkoxy chains,…

Stimulation of endothelial nitric oxide synthase by proinsulin C-peptide.

2003

There is increasing evidence for biological functions of human C-peptide. Recently, we have described that proinsulin C-peptide increases nutritive capillary blood flow and restores erythrocyte deformability in type 1 diabetic patients, whereas it has no such effect in non-diabetic subjects. The aim of the current study was to elucidate cellular mechanisms of this vasodilator effect in vitro by measuring the nitric oxide (NO)-mediated increase of cGMP production in a RFL-6 reporter cell assay and by demonstrating endothelial calcium influx with the Fluo-3 technique. C-peptide increased the release of NO from endothelial NO synthase (eNOS) in bovine aortic endothelial cells in a concentratio…

Computational Methods for Gene Expression Profiling Using Next-Generation Sequencing (RNA-Seq)

2014

Study of surface carbohydrates on isolated Golgi subfractions by fluorescent-lectin binding and flow cytometry

1995

The Golgi complex is a functionally heterogeneous subcellular structure that plays a key role in the synthesis, maturation, and sorting of newly synthesized glycoproteins. Fluorescent lectins have been used extensively to analyze surface glycoproteins by flow cytometry in whole cells and more recently in isolated subcellular organelles, such as mitochondria and chloroplasts. We report here the use of several fluorescein-isothiocyanate-conjugated lectins to detect and quantify specific surface sugars by flow cytometry on isolated elements from purified cis and trans-Golgi fractions from rat liver. Our results show that this approach may be useful to study Golgi composition and function, sinc…

Thermodynamic analysis of binding between drugs and glycosaminoglycans by isothermal titration calorimetry and fluorescence spectroscopy

2007

The thermodynamics of the interaction of positively charged drug molecules with negatively charged glycosaminoglycans (GAGs) is investigated by isothermal titration calorimetry (ITC) and fluorescence spectroscopy. The drugs considered are propranolol hydrochloride, tacrine, and aminacrine, and the polymers used as model GAGs are dextran sulfate, chondroitin sulfate, and hyaluronic acid. The ITC results show that the interaction between drugs and GAGs is via direct binding and that GAGs bind to drugs at one set of sites. Large negative values of heat capacity change (DeltaC(p)) are observed upon binding of GAGs to drugs. Such negative DeltaC(p) is not expected for purely electrostatic intera…

Highly Fluorescent and Water-Soluble Diketopyrrolopyrrole Dyes for Bioconjugation

2015

International audience; The preparation of highly water-soluble and strongly fluorescent diketopyrrolopyrrole (DPP) dyes using an unusual taurine-like sulfonated linker has been achieved. Exchanging a phenyl for a thienyl substituent shifts the emission wavelength to near λ=600 nm. The free carboxylic acid group present in these new derivatives was readily activated and the dyes were subsequently covalently linked to a model protein (bovine serum albumin; BSA). The bioconjugates were characterized by electronic absorption, fluorescence spectroscopy and MALDI-TOF mass spectrometry, thus enabling precise determination of the labeling density (ratio DPP/BSA about 3 to 8). Outstanding values of…

Cryopreservation of Escherichia coli K12TG1: Protection from the damaging effects of supercooling by freezing

2015

Injuries in living cells caused by water freezing during a freeze-thaw process have been extensively reported. In particular, intracellular water freezing has long been incriminated in cell death caused by a high cooling rate, but this supposition could not always be demonstrated. This work aims to discriminate the role of water freezing, dehydration and cold-induced injuries in cellular damage occuring during cryopreservation. For this purpose, Escherichia coli K12TG1 suspensions were maintained in a supercooled or frozen state at -20°C for times ranging from 10 min to 5 h. The supercooled state was maintained for a long period at -20°C by applying a non-injurious isostatic pressure (P<40 …