Exploring the influence of brilliant blue G on amyloid fibril formation of lysozyme.

Evidence suggests that amyloid fibril mitigation/inhibition is considered a promising approach toward treating amyloid diseases. In this work, we first examined how amyloid fibrillogenesis of lysozyme was affected by BBG, a safe triphenylmethane compound with nice blood-brain-barrier-permeability, and found that shorter fibrillar species were formed in the lysozyme samples treated with BBG. Next, alterations in the features including the secondary as well as tertiary structure, extent of aggregation, and molecular distribution of lysozyme triggered by the addition of BBG were examined by various spectroscopic techniques, right-angle light scattering, dynamic light scattering, and SDS-PAGE. In addition, we have investigated how BBG affected the lysozyme fibril-induced cytotoxicity in SH-SY5Y cells. We found that a large quantity of shorter fibrillar species and more lysozyme monomers were present in the samples treated with BBG. Also, the addition of BBG rescued SH-SY5Y cells from cell death induced by amyloid fibrils of lysozyme. Finally, information about the binding sites and interacting forces involved in the BBG-lysozyme interaction was further explored using synchronous fluorescence and molecular docking approaches. Molecular docking results revealed that, apart from the hydrophobic interaction(s), hydrogen bonding, electrostatic interactions, and van der Waal forces may also be involved in the binding interaction.

Brilliant blue R dye is capable of suppressing amyloid fibril formation of lysozyme.

Amyloid fibril formation is associated with an array of degenerative diseases. While no real cure is currently available, evidence suggests that suppression of amyloid fibrillogenesis is an effective strategy toward combating these diseases. Brilliant blue R (BBR), a disulfonated triphenylmethane compound, has been shown to interact with fibril-forming proteins but exert different effects on amyloid fibrillogenesis. These inconsistent findings prompted us to further evaluate BBR's effect on the inhibition/suppresion of protein fibrillogenesis. Using 129-residue hen lysozyme, which shares high sequence homology to human lysozyme associated with hereditary non-neuropathic systemic amyloidosis, as a model, this study is aimed at thoroughly examining the influence of BBR on the in vitro protein fibrillogenesis. We first showed that BBR dose-dependently attenuated lysozyme fibril formation probably by affecting the fibril growth rate, with the value of IC50 determined to be ~4.39 µM. Next, we employed tryptophan fluorescence quenching method to determine the binding constant and number of binding site(s) associated with BBR-lysozyme binding. In addition, we further conducted molecular docking studies to gain a better understanding of the possible binding site(s) and interaction(s) between lysozyme and BBR. We believe some of the information and/or knowledge concerning the structure-function relationship associated with BBR's suppressing activity obtained here can be applied for the future work in the subject matter related with the therapeutic strategies for amyloid diseases.

Examining the inhibitory potency of food additive fast green FCF against amyloid fibrillogenesis under acidic conditions.

More than thirty human proteins and/or peptides can fold incorrectly to form amyloid deposits associated with several protein aggregation diseases. No cure is currently available for treating these diseases. This work is aimed at examining the inhibitory potency of fast green FCF, a biocompatible dye, toward the fibrillogenesis/aggregation of lysozyme. As verified by ThT binding assay along with transmission electron microscopy, fast green FCF was observed to suppress the generation of lysozyme fibrils in a concentration-dependent manner. We next used circular dichroism absorption spectroscopy, ANS fluorescence spectroscopy, and SDS-PAGE to characterize the structural alterations in lysozyme samples upon the addition of fast green FCF. Furthermore, experiments with the addition of fast green FCF at different time points of incubation showed that fast green FCF also exhibited disaggregating activity against the preformed/existing lysozyme fibrils. We believe that the results from this study suggest a potential therapeutic role of biocompatible molecules in treating or preventing protein aggregation diseases.

A High Performance Impedance-based Platform for Evaporation Rate Detection.

This paper describes the method of a novel impedance-based platform for the detection of the evaporation rate. The model compound hyaluronic acid was employed here for demonstration purposes. Multiple evaporation tests on the model compound as a humectant with various concentrations in solutions were conducted for comparison purposes. A conventional weight loss approach is known as the most straightforward, but time-consuming, measurement technique for evaporation rate detection. Yet, a clear disadvantage is that a large volume of sample is required and multiple sample tests cannot be conducted at the same time. For the first time in literature, an electrical impedance sensing chip is successfully applied to a real-time evaporation investigation in a time sharing, continuous and automatic manner. Moreover, as little as 0.5 ml of test samples is required in this impedance-based apparatus, and a large impedance variation is demonstrated among various dilute solutions. The proposed high-sensitivity and fast-response impedance sensing system is found to outperform a conventional weight loss approach in terms of evaporation rate detection.

Amyloid fibrillogenesis of lysozyme is suppressed by a food additive brilliant blue FCF.

At least 30 different human proteins can fold abnormally to form the amyloid deposits that are associated with a number of degenerative diseases. The research presented here aimed at understanding the inhibitory potency of a food additive, brilliant blue FCF (BBF), on the amyloid fibril formation of lysozyme. Our results demonstrated that BBF was able to suppress the formation of lysozyme fibrils in a dose-dependent fashion. In addition, the structural features and conformational changes in the lysozyme samples upon the addition of BBF were further characterized using circular dichroism spectroscopy, nile red fluorescence spectroscopy, turbidity assay, and sodium dodecyl sulfate electrophoresis. Through molecular docking and molecular dynamics simulations, BBF's mechanism of action in lysozyme fibrillogenesis inhibition was found to be initiated by binding with the aggregation-prone region of the lysozyme. We believe the results from this research may contribute to the development of effective therapeutics for amyloidoses.

A real-time impedance-sensing chip for the detection of emulsion phase separation.

This paper describes a novel real-time impedance chip for the detection of squalene-water emulsion phase separation. Each impedance chip contains eight pairs of indium tin oxide microelectrode arrays for detecting eight samples, and six chips can be connected with the switch relay to measure 48 samples in the system simultaneously. The proposed impedance chip has the advantages of needing only a small sample volume (0.5 mL), and provides parallel, continuous, and real-time detection. The effects of the surfactant concentration on the stability of a squalene/water emulsion were studied by means of a visual inspection, a conductance probe, and by impedance chip. Three different concentrations of Tween 20 surfactant (9, 17, and 29 wt%) were employed for the examinations. The results indicated that the phase separation rate was faster in the lower surfactant concentration. However, the emulsion of 29 wt% Tween 20 was fairly stable for more than 2 days since there were no signal changes according to the three detection methods. The reaction time (TR) for completing the measured phase separation process differed for each of the three methods (measuring aqueous phase height, conductance, and impedance, respectively). For the 9 wt% Tween 20, the reaction times were 24 h, 20 min, and 5 min in the tests using visual inspection, conductance probe, and impedance chip, respectively. For the 17 wt% Tween 20, the TR was also shorter when using the impedance chip method compared to the other two methods. Therefore the proposed impedance chip has a quick reaction response and provides an alternative and effective method to detect emulsion stability.

Adsorption treatment of oxide chemical mechanical polishing wastewater from a semiconductor manufacturing plant by electrocoagulation.

In this study, metal hydroxides generated during electrocoagulation (EC) were used to remove the chemical oxygen demand (COD) of oxide chemical mechanical polishing (oxide-CMP) wastewater from a semiconductor manufacturing plant by EC. Adsorption studies were conducted in a batch system for various current densities and temperatures. The COD concentration in the oxide-CMP wastewater was effectively removed and decreased by more than 90%, resulting in a final wastewater COD concentration that was below the Taiwan discharge standard (100 mg L(-1)). Since the processed wastewater quality exceeded the direct discharge standard, the effluent could be considered for reuse. The adsorption kinetic studies showed that the EC process was best described using the pseudo-second-order kinetic model at the various current densities and temperatures. The experimental data were also tested against different adsorption isotherm models to describe the EC process. The Freundlich adsorption isotherm model predictions matched satisfactorily with the experimental observations. Thermodynamic parameters, including the Gibbs free energy, enthalpy, and entropy, indicated that the COD adsorption of oxide-CMP wastewater on metal hydroxides was feasible, spontaneous and endothermic in the temperature range of 288-318 K.

Removal and adsorption characteristics of polyvinyl alcohol from aqueous solutions using electrocoagulation.

The study was to investigate the performance of electrocoagulation (EC) for the efficient removal of polyvinyl alcohol (PVA) from aqueous solutions. Several parameters were evaluated to characterize the PVA removal efficiency, such as various electrode pairs, current densities, supporting electrolytes, temperatures, and initial electrolyte concentrations. The effects of the current density, supporting electrolyte, and temperature on the electrical energy consumption were also investigated. The experimental results indicate that a Fe/Al electrode pair is the optimum choice out of four different electrode pair combinations. The optimum current density, supporting electrolyte concentration, and temperature were found to be 5 mA cm(-2), 0.008 N NaCl, and 298 K, respectively. The PVA removal efficiency decreased with increasing in the initial concentrations. The kinetic studies indicated that the EC process was best described using pseudo-second-order kinetics. The experimental data were also compared to different adsorption isotherm models in order to describe the EC process. The adsorption of PVA was best fitted by the Langmuir adsorption isotherm model. Thermodynamic parameters such as the Gibbs free energy, enthalpy, and entropy indicated that the adsorption of PVA on metal hydroxides was feasible, spontaneous and endothermic in the temperature range of 288-318 K.

[(Pyrrolidin-1-yl)carbothio-ylsulfan-yl]methyl pyrrolidine-1-carbodithio-ate.

The title compound, C(11)H(18)N(2)S(4), was unexpectedly obtained during studies on the reactivity of the complex tris-(acac-κ(2)O,O')gallium(III) (acac is acetyl-acetonate) with C(4)H(8)NCS(2)H in dichloro-methane. The title compound shows disordered two pyrrolidine rings with major and minor occupancies of 0.546 (4) and 0.454 (4). Two (pyrrolidin-1-yl)carbothio-ylsulfanyl units are linked together through a methyl-ene C atom and weak C-H⋯S inter-actions are found.

Performance of COD removal from oxide chemical mechanical polishing wastewater using iron electrocoagulation.

This study investigated the feasibility of chemical oxygen demand (COD) abatement from oxide chemical mechanical polishing (oxide-CMP) wastewater. The process variables, including applied voltage, electrolyte concentration and temperature, were evaluated in terms of COD removal efficiency. In addition, the effects of applied voltage, supporting electrolyte, and temperature on electric energy consumption were evaluated. Under the optimum balance of variables, satisfactory COD removal efficiency and relatively low energy consumption were achieved. The optimum electrolyte concentration, applied voltage, and temperature were found to be 200 mg/L NaCl, 20 V, and 25 degrees C, respectively. Under these conditions, the COD concentration in oxide-CMP wastewater decreased by more than 90%, resulting a final wastewater COD concentration that was below the Taiwan discharge standard (100 mg/L). Since the processed wastewater quality exceeded the direct discharge standard, the effluent could be considered for reuse. COD removal rates obtained during the electrocoagulation process can be described using a pseudo-kinetic model. The present study results show that the kinetic data fit the pseudo first-order kinetic model well. Finally, the morphology and composition of the sludge produced were characterized using scanning electron microscopy (SEM) and energy dispersion spectra (EDS).

Electrochemical removal of indium ions from aqueous solution using iron electrodes.

The removal of indium ions from aqueous solution was carried out by electrocoagulation in batch mode using an iron electrode. Various operating parameters that could potentially affect the removal efficiency were investigated, including the current density, pH variation, supporting electrolyte, initial concentration, and temperature. The optimum current density, supporting electrolyte concentration, and temperature were found to be 6.4 mA/cm(2), 0.003N NaCl, and 298 K, respectively. When the pH values lower than 6.1, the removal efficiencies of indium ions via electrocoagulation were up to 5 times greater than those by adding sodium hydroxide. The indium ion removal efficiency decreased with an increase in the initial concentration. Results for the indium ion removal kinetics at various current densities show that the kinetic rates conformed to the pseudo-second-order kinetic model with good correlation. The experimental data were also tested against different adsorption isotherm models for describing the electrocoagulation process. The adsorption of indium ions preferably fitting the Langmuir adsorption isotherm suggests monolayer coverage of adsorbed molecules.

Study of COD and turbidity removal from real oxide-CMP wastewater by iron electrocoagulation and the evaluation of specific energy consumption.

This study explores the feasibility of reducing COD and turbidity from real oxide chemical mechanical polishing (oxide-CMP) wastewater. Based on the dynamic characteristics of batch electrocoagulation, three operating stages (lag, reactive, and stabilizing) are proposed to identify the relationships among the zeta potential of the silica particles, solution turbidity, and the corresponding mean particle size. Experiment results show that the silica particles were destabilized and settled at the critical electrolysis time, which was estimated to be about 12 min under an applied voltage of 20 V and a supporting electrolyte of 200mg/L. The corresponding turbidity removal occurred mostly during the reactive stage. The process variables, including applied voltage and electrolyte concentration, were investigated in terms of COD removal efficiency and turbidity removal. In addition, the effects of applied voltage and supporting electrolyte on COD removal efficiency and specific energy consumption were evaluated. Under the optimum balance, satisfactory removal efficiency and relatively low energy consumption were obtained. The optimum electrolyte concentration and applied voltage were found to be 200mg/L NaCl and 20 V, respectively. Under the optimum conditions, COD and turbidity decreased by more than 90% and 98% in real oxide-CMP wastewater, respectively.

Paired removal of color and COD from textile dyeing wastewater by simultaneous anodic and indirect cathodic oxidation.

The anodic and indirect cathodic removals of color and COD from real dyeing wastewater were investigated simultaneously using a stacked Pt/Ti screen anode and a graphite packed-bed cathode in a divided flow-by electrochemical reactor. The anodically generated hypochlorite and cathodically generated hydrogen peroxide were the main species used to remove color and COD in the wastewater. Various experimental operating factors that can affect the removal efficiency were investigated, including the applied current density, the amount of NaCl added, the solution pH in alkaline ranges and the temperature. The color and COD removal efficiencies in the anodic chamber were much higher than those in the cathodic chamber. The overall (anodic plus cathodic) removal efficiencies increased with the applied current density, the amount of NaCl added and the temperature. In contrast, increasing the solution pH decreased the overall removal efficiency. The anodic and cathodic current efficiencies at 20 mA/cm(2) were 63.50% and 19.57%, respectively. In this work the total treatment cost for removing 1g COD was US $0.643 when an air cylinder was used.

Effect of operating parameters on indium (III) ion removal by iron electrocoagulation and evaluation of specific energy consumption.

The aim of this study is to investigate the effects of operating parameters on the specific energy consumption and removal efficiency of synthetic wastewater containing indium (III) ions by electrocoagulation in batch mode using an iron electrode. Several parameters, including different electrode pairs, supporting electrolytes, initial concentration, pH variation, and applied voltage, were investigated. In addition, the effects of applied voltage, supporting electrolyte, and initial concentration on indium (III) ion removal efficiency and specific energy consumption were investigated under the optimum balance of reasonable removal efficiency and relative low energy consumption. Experiment results indicate that a Fe/Al electrode pair is the most efficient choice of the four electrode pairs in terms of energy consumption. The optimum supporting electrolyte concentration, initial concentration, and applied voltage were found to be 100 mg/l NaCl, 20 mg/l, and 20V, respectively. A higher pH at higher applied voltage (20 or 30V) enhanced the precipitation of indium (III) ion as insoluble indium hydroxide, which improved the removal efficiency. Results from the indium (III) ion removal kinetics show that the kinetics data fit the pseudo second-order kinetic model well. Finally, the composition of the sludge produced was characterized with energy dispersion spectra (EDS).

Silica particles settling characteristics and removal performances of oxide chemical mechanical polishing wastewater treated by electrocoagulation technology.

The purpose of this study was to explore the feasibility of removing silica particles and reducing turbidity from oxide chemical mechanical polishing (oxide-CMP) wastewater. Based on the dynamic characteristics of batch electrocoagulation, three operating stages (lag, reactive, and stabilizing) are proposed to identify the relationships among the zeta potential of the silica particles, solution turbidity, and the corresponding mean particle size of the silica. Experimental results show that the silica particles were destabilized and settled at the critical mean particle size, which was estimated to be above 520nm after 10min, and the corresponding turbidity removal mostly occurred during the reactive stage. Furthermore, the corresponding mean particle size varied from 520 to 1900nm as the treatment time progressed from 10 to 20min, which also occurred during the reactive stage. Several parameters, including different electrode pairs, electrolyte concentration, applied voltage, and the optimum condition of power input were investigated. Experimental results indicate that a Fe/Al electrode pair is the most efficient choice of the four electrode pair combinations in terms of energy consumption. The optimum electrolyte concentration and applied voltage were found to be 200ppm NaCl and 30V, respectively.

Removal of COD from laundry wastewater by electrocoagulation/electroflotation.

The removal efficiency of COD in the treatment of simulated laundry wastewater using electrocoagulation/electroflotation technology is described. The experimental results showed that the removal efficiency was better, reaching to about 62%, when applying ultrasound to the electrocoagulation cell. The solution pH approached neutrality in all experimental runs. The optimal removal efficiency of COD was obtained by using the applied voltage of 5V when considering the energy efficiency and the acceptable removal efficiency simultaneously. The Cl(-) concentration of less than 2500ppm had a positive effect on the removal efficiency. The performance of the monopolar connection of electrodes was better than that of the bipolar connection in this work. In addition, the removal efficiency of using Al electrodes was higher in comparison with using Fe electrodes in the study. The highest COD removal amount per joule was found to be 999mgdm(-3)kWh(-1) while using two Al electrodes, although the removal efficiency increased with the number of Al plates.

Removal of gallium (III) ions from acidic aqueous solution by supercritical carbon dioxide extraction in the green separation process.

Supercritical carbon dioxide extraction, which is a feasible "green" alternative, was applied in this study as a sample pretreatment step for the removal of gallium (III) ions from acidic aqueous solution. The effect of various process parameters, including various chelating agents, extraction pressure and temperature, dimensionless CO(2) volume, the concentration of the chelating agent, and the pH of the solution, governing the efficiency and throughput of the procedure were systematically investigated. The performance of the various chelating agents from different studies indicated that the extraction efficiency of supercritical CO(2) was in the order: thiopyridine (PySH)>thenoyltrifluoroacetone (TTAH)>acetylacetone (AcAcH). The optimal extraction pressure and temperature for the supercritical CO(2) extraction of gallium (III) with chelating agent PySH were found to be 70 degrees C and 3000psi, respectively. The optimum concentration of the chelating agent was found to be 50ppm. A value of 7.5 was selected as the optimum dimensionless CO(2) volume. The optimum pH of the solution for supercritical CO(2) extraction should fall in the range of 2.0-3.0.

Removal of color from real dyeing wastewater by Electro-Fenton technology using a three-dimensional graphite cathode.

This work investigates the removal of color from wastewater that contains low dyestuff concentrations by the Electro-Fenton process. The color was removed by in situ electrogenerated hydrogen peroxides at a three-dimensional graphite cathode with added ferrous sulfates. Experimental runs were conducted to evaluate the effect of the operating parameters, such as the oxygen contact mode, the oxygen sparging rate, the applied current density, the concentration of ferrous ions, the solution temperature and the pH among others, on the removal of color. The removal efficiency of the color in the cathodic chamber reached 70.6% under specified operation conditions in 150 min. The removal efficiency was controlled by the mass transfer when the oxygen-sparging rate was less than 0.3 dm(3)/min for the reactor configuration herein. The optimal applied current density was 68 A/m(2) when the energy consumption was considered. The highest removal efficiency was obtained by adding 20 mM Fe(II) to the solution. The optimal solution pH was 3 in this work. The temperature negatively affected color removal.

Effect of various chelating agents on supercritical carbon dioxide extraction of indium(III) ions from acidic aqueous solution.

Indium and its compounds have numerous industrial applications in the manufacture of liquid crystal displays and semiconductors. Indium compounds are considered hazardous materials that can be carcinogenic. Supercritical fluid extraction using carbon dioxide was utilized in this research as a sample pretreatment step for extraction of indium(III) ions from the synthetic etching wastewater of the semiconductor and optoelectronic industries. Several parameters, including various chelating agents, pH of solution, molar ratio of chelating agent to indium(III) ions, temperature and pressure were systematically investigated. Indium(III) ions were extracted by supercritical CO2 combined with several various types of chelating agents including beta-diketone (AcAcH), fluorinated beta-diketone (TTAH), thiopyridine (PySH), and piperidinyldithiocarbamic acid (NCS2H) to extract the ions from acidic aqueous solution. The performance of the various chelating agents from different studies indicated that the extraction efficiency by the supercritical CO2 was in the order: NCS2H>or==PySH>TTAH>>AcAcH. The optimum pH for supercritical CO2 extraction should fall in the range from 2.0 to 3.0. The optimum molar ratio of chelating agents to indium(III) ions was found to be a ratio of 10:1. It was also revealed that the optimal extraction pressure and temperature for the supercritical CO2 extraction of indium(III) with various chelating agents AcAcH, PySH and NCS2H were 70 degrees C 2000 psi, 60 degrees C 2000 psi, and 60 degrees C 2000 psi, respectively.