Dye Diffusion Research Articles

A quantitative model of charge injection by ruthenium chromophores connecting femtosecond to continuous irradiance conditions.

A kinetic framework for the ultrafast photophysics of tris(2,2-bipyridine)ruthenium(II) phosphonated and methyl-phosphonated derivatives is used as a basis for modeling charge injection by ruthenium dyes into a semiconductor substrate. By including the effects of light scattering, dye diffusion, and adsorption kinetics during sample preparation and the optical response of oxidized dyes, quantitative agreement with multiple transient absorption datasets is achieved on timescales spanning femtoseconds to nanoseconds. In particular, quantitative agreement with important spectroscopic handles-the decay of an excited state absorption signal component associated with charge injection in the UV region of the spectrum and the dynamical redshift of a ∼500nm isosbestic point-validates our kinetic model. Pseudo-first-order rate coefficients for charge injection are estimated in this work, with an order of magnitude ranging from 1011 to 1012s-1. The model makes the minimalist assumption that all excited states of a particular dye have the same charge injection coefficient, an assumption that would benefit from additional theoretical and experimental exploration. We have adapted this kinetic model to predict charge injection under continuous solar irradiation and find that as many as 68 electron transfer events per dye per second take place, significantly more than prior estimates in the literature.

The IgCAM CAR Regulates Gap Junction-Mediated Coupling on Embryonic Cardiomyocytes and Affects Their Beating Frequency.

The IgCAM coxsackie-adenovirus receptor (CAR) is essential for embryonic heart development and electrical conduction in the mature heart. However, it is not well-understood how CAR exerts these effects at the cellular level. To address this question, we analyzed the spontaneous beating of cultured embryonic hearts and cardiomyocytes from wild type and CAR knockout (KO) embryos. Surprisingly, in the absence of the CAR, cultured cardiomyocytes showed increased frequencies of beating and calcium cycling. Increased beatings of heart organ cultures were also induced by the application of reagents that bind to the extracellular region of the CAR, such as the adenovirus fiber knob. However, the calcium cycling machinery, including calcium extrusion via SERCA2 and NCX, was not disrupted in CAR KO cells. In contrast, CAR KO cardiomyocytes displayed size increases but decreased in the total numbers of membrane-localized Cx43 clusters. This was accompanied by improved cell-cell coupling between CAR KO cells, as demonstrated by increased intercellular dye diffusion. Our data indicate that the CAR may modulate the localization and oligomerization of Cx43 at the plasma membrane, which could in turn influence electrical propagation between cardiomyocytes via gap junctions.

Adhesion of Polymer to TiO2 Particles Decreases Photocatalytic Activity of Polyelectrolyte Hydrogel Photocatalyst

AbstractA comparative study on the photocatalytic activity was done for TiO2/poly(acrylamide‐co‐potassium acrylate) composite hydrogels with varying content of potassium acrylate monomer units. The presence of the acrylate units led to the increase in the swelling ratio of hydrogel and to the enhancement of the diffusion of the methyl orange probe dye to the surface of the embedded TiO2 particles. However, the photocatalytic activity was not improved. Microcalorimetry data showed that while the enthalpy of polymer adhesion to the TiO2 particles surface was positive in the case of polyacrylamide and it became negative if acrylate units were included in the polymer network. Likely, the adhesion enhancement occurred due to the electrostatic interaction among acrylate monomer units and surface of TiO2 particles. As a result of polymer adhesion to the active surface of the catalyst particles was partly blocked and the photocatalytic activity of the composite hydrogel diminished.

Photostable Small-Molecule NIR-II Fluorescent Scaffolds that Cross the Blood-Brain Barrier for Noninvasive Brain Imaging.

The second near-infrared (NIR-II, 1000-1700 nm) fluorescent probes have significant advantages over visible or NIR-I (600-900 nm) imaging for both depth of penetration and level of resolution. Since the blood-brain barrier (BBB) prevents most molecules from entering the central nervous system, NIR-II dyes with large molecular frameworks have limited applications for brain imaging. In this work, we developed a series of boron difluoride (BF2) formazanate NIR-II dyes, which had tunable photophysical properties, ultrahigh photostability, excellent biological stability, and strong brightness. Modulation of the aniline moiety of BF2 formazanate dyes significantly enhances their abilities to cross the BBB for noninvasive brain imaging. Furthermore, the intact mouse brain imaging and dynamic dye diffusion across the BBB were monitored using these BF2 formazanate dyes in the NIR-II region. In murine glioblastoma models, these dyes can differentiate tumors from normal brain tissues. We anticipate that this new type of small molecule will find potential applications in creating probes and drugs relevant to theranostic for brain pathologies.

The influence of electrolytes in the adsorption kinetics of reactive BF-5G blue dye on bone char: a mass transfer model

ABSTRACT The discharge of harmful dyes in water bodies is a serious pollution problem, dangerous for the ecosystem’s equilibrium and human health. In this sense, the aim of this work was to determine the influence of electrolytes (NaCl, KCl, CaCl2 and MgCl2) in the adsorption of Reactive Blue BF-5G dye, the most common dye used in industrial process for fabric colouring, using bovine bone char as the adsorbent. The bovine bone char was characterized by pH of point of zero charge (pHPZC), N2 adsorption–desorption isotherms, Fourier transform-infrared spectroscopy (FT-IR) and X-ray diffractometry (XDR). The characterization revealed a mesoporous structure (pore mean diameter of 94 Å and SBET ∼107 m2 g-1) with negative charge distribution at the surface (pHPZC = 3.8). The adsorption experiments revealed that the presence of KCl enhanced the material adsorption capacity (q max = 195 mg g−1), that the Sips isotherm best fitted the experimental data (R 2 > 0.9 except for KCl solution) and the adsorption process was mono- and multilayered. The kinetic adsorption experiments indicated that the inorganic electrolytes increased the initial adsorption velocity and the data was best modelled by the surface diffusional model (SDM), implying a resistance (aqueous > CaCl2 > NaCl > MgCl2 > KCl) to mass transfer at the surface of the pores which, in turn, prevented the dye diffusion to the interior of the adsorbent (qe = 71 mg g−1). Therefore, small quantities of KCl can be used to lower the mass transfer resistance and provide higher adsorption capacity with reduced time of operation, thus increasing the overall process efficiency.

Chemical nature of dye interaction when dying fur sheepskin

The article substantiates the use of active dyes with vinylsulfone and chlorotriazine groups in leather and fur production in order to obtain fur sheepskin with an improved set of consumer properties. The kinetic regularities of the processes of diffusion, fixation and hydrolysis of active dyes have been studied. This makes it possible to increase the efficiency of the process of dyeing fur sheepskin and the completeness of the use of active dyes. In monofunctional active bright blue 53Sh, only 56.7 % of 72.2 % of the total amount of sorbed dye is fixed by covalent bonds, in mono-bifunctional active brown - 65.9 % of 73.7 %, in hetero-bifunctional active bright red 5CX - 71.6 % of 77.1 %. The anomalous nature of the chemical reactions of active dyes with water and with woolen fiber has been established. The practical significance lies in the development of theoretical foundations for predicting changes in the degree of fixation and the efficiency indicator of the process of dyeing fur sheepskin under the influence of temperature, pH and other factors.

Fluorescence correlation spectroscopy based insights into diffusion in electrochemical energy systems

Fluorescence Correlation Spectroscopy, a commonly used technique for measuring diffusion of biomolecules and tracer dyes in different solvents, is employed to characterise the local transport properties in battery electrolytes. Diffusion of ions, a major limiting factor in battery capacity and charging rates, depends on the local interactions and structuredness of the electrolytic species. Structuredness in the electrolyte results from typical solvation behaviour of diffusing ions/molecules leading to long-range interactions. In this work, we have used FCS to measure tracer diffusion of Coumarin 343 in a mixture of Ethylene Carbonate (EC) and Dimethyl Carbonate (DMC), commonly used as electrolyte solvent in Li-ion batteries. The measured diffusion is found to depend on lithium-ion concentrations. It is found that the addition of LiPF6 to an EC-DMC equimolar mixture slows down tracer diffusion significantly. Indeed, the bulk viscosity of the electrolyte added with LiPF6 salt varies with salt concentration. However, the change in bulk viscosity (global behaviour) at high ion concentrations does not match the one inferred from applying Stoke-Einstein’s relation to the diffusion data (local behaviour). This indicates that the homogeneity of the electrolyte does not extend spatially to molecular scales around the diffusing tracer molecule. Measurements made on coin cells prepared with different concentrations of LiPF6 show battery performance limited at higher concentrations, characterized by specific capacity loss at faster charging cycles. This limitation is directly related to the local behaviour of the electrolyte as quantified by measurements of tracer diffusion, which slows down, which remarkably outweighs the advantage of high carrier densities.

Determination of In Vitro and Cellular Turn-on Kinetics for Fluorogenic RNA Aptamers.

Fluorogenic RNA aptamers have been applied in live cells to tag and visualize RNAs, report on gene expression, and activate fluorescent biosensors that detect levels of metabolites and signaling molecules. In order to study dynamic changes in each of these systems, it is desirable to obtain real-time measurements, but the accuracy of the measurements depends on the kinetics of the fluorogenic reaction being faster than the sampling frequency. Here, we describe methods to determine the in vitro and cellular turn-on kinetics for fluorogenic RNA aptamers using a plate reader equipped with a sample injector and a flow cytometer, respectively. We show that the in vitro kinetics for the fluorescence activation of the Spinach2 and Broccoli aptamers can be modeled as two-phase association reactions and have differing fast phase rate constants of 0.56 s-1 and 0.35 s-1, respectively. In addition, we show that the cellular kinetics for the fluorescence activation of Spinach2 in Escherichia coli, which is further limited by dye diffusion into the Gram-negative bacteria, is still sufficiently rapid to enable accurate sampling frequency on the minute timescale. These methods to analyze fluorescence activation kinetics are applicable to other fluorogenic RNA aptamers that have been developed.

CdS@NiCo-LDH hybrid photoelectrocatalyst with enhanced photocatalytic activity: A convenient and stable hybrid for wastewater treatment

In many wastewater treatment processes, the discovery of cost-effective electrocatalysts is very important for photoelectrocatalytic reactions. This paper reports a suitable method for the synthesis of high efficiency hybrid photoelectrocatalyst consisting of NiCo layered double hydroxide and CdS, called [email protected] 3-D [email protected] electrode was fabricated on a nickel foam using hydrothermal synthesis. The synthesized electrode showed high specific surface area, efficient electron transportation, and long-term stability. The pH, bias potential, reaction temperature, and dye concentration were evaluated for the degradation of Allura Red in aqueous solution using the synthesized photoelectrocatalyst. TOC and COD of the dye solution were also investigated. The layered architecture of the [email protected] composite provided more accessible surface for the diffusion of dye and gaseous molecules. The photoelectrocatalyst exhibited excellent stability in the degradation process and the results proved the efficiency of the suggested procedure for dye degradation.

Revisiting the Temperature Dependence of Protein Diffusion inside Bacteria: Validity of the Stokes-Einstein Equation.

Although the transport and mixing of proteins and other molecules inside bacteria rely on the diffusion of molecules, many aspects of the molecular diffusion in bacterial cytoplasm remain unclear or controversial, including how the diffusion-temperature relation follows the Stokes-Einstein equation. In this study, we applied single-particle tracking photoactivated localization microscopy to investigate the diffusion of histonelike nucleoid structuring (HNS) proteins and free dyes in bacterial cytoplasm at different temperatures. Although the diffusion of HNS proteins in both live and dead bacteria increased at higher temperatures and appeared to follow the Arrhenius equation, the diffusion of free dyes decreased at higher temperatures, questioning the previously proposed theories based on superthermal fluctuations. To understand the measured diffusion-temperature relations, we developed an alternative model, in which the bacterial cytoplasm is considered as a polymeric network or mesh. In our model, the Stokes-Einstein equation remains valid, while the polymeric network contributes a significant term to the viscosity experienced by the molecules diffusing in bacterial cytoplasm. Our model was successful in predicting the diffusion-temperature relations for both HNS proteins and free dyes in bacteria. In addition, we systematically examined the predicted diffusion-temperature relations with different parameters in the model, and predicted the possible existence of phase transitions.

A Print-and-Fuse Strategy for Sacrificial Filaments Enables Biomimetically Structured Perfusable Microvascular Networks with Functional Endothelium Inside 3D Hydrogels.

A facile and flexible approach for the integration of biomimetically branched microvasculature within bulk hydrogels is presented. For this, sacrificial scaffolds of thermoresponsive poly(2-cyclopropyl-2-oxazoline) (PcycloPrOx) are created using melt electrowriting (MEW) in an optimized and predictable way and subsequently placed into a customized bioreactor system, which is then filled with a hydrogel precursor solution. The aqueous environment above the lower critical solution temperature (LCST) of PcycloPrOx at 25°C swells the polymer without dissolving it, resulting in fusion of filaments that are deposited onto each other (print-and-fuse approach). Accordingly, an adequate printing pathway design results in generating physiological-like branchings and channel volumes that approximate Murray's law in the geometrical ratio between parent and daughter vessels. After gel formation, a temperature decrease below the LCST produces interconnected microchannels with distinct inlet and outlet regions. Initial placement of the sacrificial scaffolds in the bioreactors in a pre-defined manner directly yields perfusable structures via leakage-free fluid connections in a reproducible one-step procedure. Using this approach, rapid formation of a tight and biologically functional endothelial layer, as assessed not only through fluorescent dye diffusion, but also by tumor necrosis factor alpha (TNF-α) stimulation, is obtained within three days.

Effect of H2O/DMF mixed solvents on formation of MIL-100(Fe) and dye adsorption

MIL-100(Fe) with microporous structures is often synthesized under conventional hydrothermal conditions using iron ion and trimesic acid. The effect of H2O/dimethylformamide (DMF) mixtures, with variable H2O volume ratios, on the formation of MIL-100(Fe) was investigated under solvothermal conditions. Pure octahedral MIL-100(Fe) could only be formed in neat H2O or DMF. In most cases, the same reaction in mixed H2O/DMF solvents afforded goethite. When a small volume of H2O was used, morphology resembled coexisting octahedra of MIL-100(Fe) and hexagonal platelets of goethite. A subsequent increase in the H2O content yielded pure hexagonal platelets of goethite and then hexagonal bipyramidal structures of hematite. The surface area and pore volume of MIL-100(Fe) were higher than those of goethite. Dye adsorption tests revealed that 80% of methylene blue (MB) was adsorbed on MIL-100(Fe), synthesized in pure DMF, within 5 ​min, whereas only approximately 26% was adsorbed on MIL-100(Fe) synthesized in pure H2O. This can be attributed to the nanoscale hierarchically porous structures with macroporosity in the DMF-synthesized MIL-100(Fe) and enhanced fast diffusion and mass transfer of dye, which demonstrates its potential as an adsorbent for dye removal. Thus, this study provides a new option of solvent for the formation of nanoscale hierarchically porous MIL-100(Fe) with improved performance in various practical applications.

Evaluation of Microleakage Using Dye-penetration Method in Three Different Composite Resin Core Build-up Materials: An In Vitro Study

Aim of the current research is to establish and assess the microleakage in bulk-fill composite, nanohybrid ormocer-based resins, and nanofilled composite resin core build-up materials employing the dye-penetration technique. Sixty human mandibular first premolar teeth with a solitary root canal without dental caries were chosen for this research. Each specimen was subjected to decoronation of 2 mm from the cementoenamel junction (CEJ), following which the root canal treatment procedure was rendered complete. A space for the post was made for all the 60 samples. Following positioning of the post, specimens were allocated into one of the following three investigational groups (20 specimens in every group) on the basis of the core build-up materials used as group I: bulk-fill composites, group II: nanohybrid ormocer-based resins, and group III: nanofilled resin composites. Direct composite was used for core build-up and subjected to light-curing. Following this, the specimens were immersed in 1% methylene blue solution for 24 hours interval. Each section was evaluated for dye diffusion employing a stereomicroscope with software at a magnifying power of 40× and surface contact between dentin and base of the material was evaluated under scanning electron microscope. Nanohybrid ormocer-based composites exhibited the least microleakage at 1.12 ± 0.14, in pursuit by nanofilled composite resins at 1.79 ± 0.09, and finally the bulk-fill composites at 2.85 ± 0.11, amid the investigational groups studied. A statistically significant difference amid the three dissimilar cores buildup substances was found upon analysis of variance. Despite the study limitations, this research came to a conclusion that each of the three investigated core build-up substances exhibited microleakage. However, amid the three, nanohybrid ormocer-based composites depicted the lowest amount of microleakage in pursuit by the nanofilled resins and the bulk-fill composites. Core build-up is an important requirement as the remaining tooth substance following root canal treatment reduces and needs reinforcement with core build-up to sustain the tooth structure and provide resistance. A vital mandate for enduring efficiency of the restoration in the mouth is high-quality adhesive bond of these agents to cavity walls with diminished microleakage.

ECO-FRIENDLY TECHNOLOGY FOR REACTIVE DYEING OF CATIONIZED FABRICS: PROTIC IONIC LIQUIDS AS INNOVATIVE MEDIA

Because of the limitations of traditional dyeing technologies, large amounts of water and chemical additives are used in the dyeing processes, resulting in enormous quantities of polluted wastewater, which has a huge health and environmental potential impact. In the last few years, the interest in researching alternative techniques/materials for the textile industry to reduce the consumption of water used to improve dyeing quality, has considerably increased. Continuing previous research, in this paper, we present a non-aqueous dyeing procedure, testing different types of fabrics with a polyfunctional reactive dye and protic ionic liquids (PILs) as reaction environment, and with cationization pretreatment of the tested fibers. To analyze the effectiveness of the proposed procedure, currently established dyeing quality parameters, such as color absorption and wash fastness of the dyed multifiber fabrics, have been measured and analysed. The obtained dyeing results should be explained by the affinity of cationized multifibers to the reactive dye, as well as by the efficiency of the mechanisms of dye diffusion and chemical bonding on the tested fabrics in protic ionic liquid environment. This new proposed “universal dye” for all kinds of fibers in PIL environment was analyzed under different operational dyeing conditions. The obtained results were satisfying when compared with standard dyeing quality parameters reported in earlier published literature, thus opening opportunities for innovation and optimization.

Electromagnetic Navigation Transthoracic Nodule Localization for Minimally Invasive Thoracic Surgery.

The increased use of chest computed tomography (CT) has led to an increased detection of pulmonary nodules requiring diagnostic evaluation and/or excision. Many of these nodules are identified and excised via minimally invasive thoracic surgery; however, subcentimeter and subsolid nodules are frequently difficult to identify intra-operatively. This can be mitigated by the use of electromagnetic transthoracic needle localization. This protocol delineates the step-by-step process of electromagnetic localization from the pre-operative period to the postoperative period and is an adaptation of the electromagnetically guided percutaneous biopsy previously described by Arias et al. Pre-operative steps include obtaining a same day CT followed by the generation of a three-dimensional virtual map of the lung. From this map, the target lesion(s) and an entry site are chosen. In the operating room, the virtual reconstruction of the lung is then calibrated with the patient and the electromagnetic navigation platform. The patient is then sedated, intubated, and placed in the lateral decubitus position. Using a sterile technique and visualization from multiple views, the needle is inserted into the chest wall at the prechosen skin entry site and driven down to the target lesion. Dye is then injected into the lesion and, then, continuously during needle withdrawal, creating a tract for visualization intra-operatively. This method has many potential benefits when compared to the CT-guided localization, including a decreased radiation exposure and decreased time between the dye injection and the surgery. Dye diffusion from the pathway occurs over time, thereby limiting intra-operative nodule identification. By decreasing the time to surgery, there is a decrease in wait time for the patient, and less time for dye diffusion to occur, resulting in an improvement in nodule localization. When compared to electromagnetic bronchoscopy, airway architecture is no longer a limitation as the target nodule is accessed via a transparenchymal approach. Details of this procedure are described in a step-by-step fashion.

Testing the suitability of neuroanatomical tracing method in human fetuses with long years of postmortem delay.

Human tissues in gross anatomical archives with long years of postmortem delays are considered suboptimal relative to recently fixed materials for neuroanatomical tracing studies, yet efficacy of neuroanatomical tracing on archival fetal tissues largely unexplored. We aimed to explore the suitability of human archival tissue in neuroanatomical tracing with lipophilic carbocyanine dyes. We used crystal and paste forms 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI) and analogues for neuroanatomical tracing on different peripheral nerves in 15-18-year archival old formalin-fixed human fetuses. We employed bright-field, fluorescent and confocal microscopy to visualize the peripheric nerve traces, spinal cord and vibratome cut sections. Fluorescent signal of the dyes on epineurium and on axonal membranes were visualized under fluorescence and confocal microscopes and performance of the dye diffusion was assessed by semi-quantitative image analysis. We followed up seven lipophilic dye embeddings in 16-28 gestational week-old human fetuses (n = 4) with 16.75 ± 1.29-year postmortem delay. The mean distance of distally moved carbocyanine dye diffusion measured on epineurium was detected as 25.11 ± 9.1mm. Based on the results of 13 distinct studies performed neuroanatomical tracing with human tissues in the immediate postmortem hours or days, average traced distance was 16.32 ± 15.95mm, and a 95% confidence interval lower limit of 4.9mm and upper limit of 27.73mm. The tracing distances we observed in our current study fall entirely within this confidence interval. To our awareness, this is the first report to demonstrate that specific neuroanatomical tracing presented in axonal membrane level on peripheral nerves is possible on gross anatomical repositories.

The roles of polymer relaxation phenomena, aqueous dye solubility and the physical properties of water in the mechanism of adsorption of a disperse dye on poly(ethylene terephthalate) fibres: Part 1 polymer relaxation phenomena

AbstractTo investigate the contributions of polymer relaxation phenomena to the mechanism of disperse dye adsorption on poly(ethylene terephthalate) fibres, a commercial grade dye was applied to poly(ethylene terephthalate) fabric at temperatures between 30°C and 130°C. Three regions of temperature‐dependent dyeing behaviour were identified, in which the promotional effect imparted by increasing dyeing temperature varied, depending on whether dyeing had been carried out at temperatures that were below, within or above the polymer's glass transition temperature, Tg, namely < 65°C, between 65°C and 110°C and between 110°C and 130°C, respectively. When experimentally determined colour strength data points (log 1/fk) were fitted to plots of polymer structural relaxation (log aT) calculated using the Williams, Landel and Ferry equation as a function of (T − Tg), three different levels of correspondence were achieved which paralleled the observed three regions of temperature‐dependent dye uptake. The adsorption of the commercial disperse dye on the poly(ethylene terephthalate) fibre therefore concurs with the free volume model of dye diffusion insofar as the diffusional behaviour of the dye is related to the relaxation time of the molecular motions occurring within the poly(ethylene terephthalate) polymer. The finding that the poly(ethylene terephthalate) substrate's glass transition extends over a broad range of temperature upto ~110°C explains why elevated dyeing temperatures in the region of 130/140°C must be used in High Temperature dyeing processes, and also, why ~75% of uptake of the commercial disperse dye on the poly(ethylene terephthalate) fabric occurs over the very narrow 20‐30°C critical temperature range between 110 and 130°C/140°C.

Salts and water‐free dyeing of cellulose nanofibers using novel green deep eutectic solvents: Isotherm, kinetics, and thermodynamic studies

AbstractRecently, dyeing of cellulose nanofibers (CNF) has gained substantial interest due to its multifunctional properties, but discharge of hazardous effluent containing salts are biggest challenges for sustainability for textile processing sectors. Herein, we report deep eutectic solvents (DES) as a novel green dyeing medium to dye CNF with anionic reactive dyes (without salts) for the first time and dyeing parameters were optimized. Dyed CNF in DES showed 37% higher color yield compared to CNF dyed in conventional dyeing medium (with auxiliaries). The diffusion and standard affinity of both reactive dyes towards CNF in DES medium were greater than conventional (CN) medium. CNF dyed in DES revealed smooth morphology and the presence of reactive dyes confirmed by FTIR, it also offers enhanced wettability, and good color fastness properties. Therefore, DES can potentially be utilized as an effective dyeing medium.

Generation and Characterization of an Inducible Cx43 Overexpression System in Mouse Embryonic Stem Cells.

Connexins (Cx) are a large family of membrane proteins that can form intercellular connections, so-called gap junctions between adjacent cells. Cx43 is widely expressed in mammals and has a variety of different functions, such as the propagation of electrical conduction in the cardiac ventricle. Despite Cx43 knockout models, many questions regarding the biology of Cx43 in health and disease remain unanswered. Herein we report the establishment of a Cre-inducible Cx43 overexpression system in murine embryonic stem (ES) cells. This enables the investigation of the impact of Cx43 overexpression in somatic cells. We utilized a double reporter system to label Cx43-overexpressing cells via mCherry fluorescence and exogenous Cx43 via fusion with P2A peptide to visualize its distribution pattern. We proved the functionality of our systems in ES cells, HeLa cells, and 3T3-fibroblasts and demonstrated the formation of functional gap junctions based on dye diffusion and FRAP experiments. In addition, Cx43-overexpressing ES cells could be differentiated into viable cardiomyocytes, as shown by the formation of cross striation and spontaneous beating. Analysis revealed faster and more rhythmic beating of Cx43-overexpressing cell clusters. Thus, our Cx43 overexpression systems enable the investigation of Cx43 biology and function in cardiomyocytes and other somatic cells.

Synthesis of chitosan/MnFe2O4 @ reduced graphene oxide aerogel with radial passageway and its application in removing methylene blue from water

Constructing a radial passageway is an effective strategy to promote the diffusion of organic dyes from edge to center of aerogels, benefiting to that organic dyes approach catalysts and subsequently are decomposed. With regard to this concept, in this work, MnFe2O4-decorated reduced graphene oxide (MG), coupling with chitosan (CS), were used to obtain aerogels with a radial passageway. Morphology and catalytic effectiveness of the resultant CS/MG aerogels were characterized in detail. It was found that the as-prepared aerogels presented high activity in degrading organic dyes (for example, methylene blue). In addition, the reaction kinetic was comprehensively studied and followed the pseudo-first-order model. Based on the experimental results, the maximum decomposition degree of methylene blue solution containing the resultant aerogel was up to 83.9% in 240 min. Therefore, the resultant aerogel acts as a potential catalyst for degradation of methylene blue present in water.