Fabrication of rGO/Fe3O4 Magnetic Composite for the Adsorption of Anthraquinone-2-Sulfonate in Water Phase

In the last few decades, anthraquinone and its derivatives (AQs) have been intensively applied to electrochemical, textile and dye, and photovoltaic industries. This has increased the levels of AQs in the natural environment and threatens human health. To remove AQs from the aqueous phase and recover these multi-functional molecules, a binary magnetic adsorbent, reduced graphene/Fe3O4 (rGO/Fe3O4), was synthesized via a hydrothermal method. Transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), Raman spectra, and thermogravimetric analysis (TGA) were then used to characterize the samples. The adsorption capacities of rGO/Fe3O4 to AQs were investigated by selecting anthraquinone-2-sulfonate (AQ2S) as a model molecule. The adsorption process followed the Langmuir adsorption isotherm and the second-order kinetics. The regeneration of adsorbents and the recycling of AQ2S and solvent were simultaneously achieved by Soxhlet extraction and rotary evaporation. These results confirm the high adsorption efficiency of rGO/Fe3O4 for removing AQs from water and provide a promising approach to recover the valuable molecules from the aqueous phase.

The Effects of the Rotational Speed of the Deposition Substrate on the Morphological and Current Injection Characteristics of LiF Thin Films

In this study, we report the effects of the substrate rotational speed on the morphological characteristics of lithium fluoride (LiF) during thermal evaporation. LiF is used as a typical material in a vacuum-level shift-based electron injection layer and can improve both the charge injection and light emission properties when inserted into the electrode/organic material interface of organic light-emitting diodes (OLEDs). In general OLED research, rotary evaporation is widely used to ensure uniformity. However, there are few reports regarding the effects of this rotary evaporation method on the morphological characteristics of the thin films. Therefore, in this study, we analyzed the effects of rotary variations on the morphological and electron injection characteristics during deposition. The root mean square roughness of the LiF thin film deposited on Alq3 changed by up to 12.3%. Additionally, the driving voltage of the electron-only device showed a difference of 2.3 V at maximum and a change in the slope of the ohmic region was demonstrated. The morphological change in the LiF thin film based on the rotational speed of the substrate had a significant influence on the reaction at the electrode/organic material interface.

Development and Characterization of Elastic Liposomes of Metronidazole for the Treatment of Bacterial Infection

Objective: The objective of present study is to develop and evaluate the elastic liposomes of metronidazole so as to provide the sustained release and improve its bioavailability. Methods: Elastic liposomes were prepared by rotary evaporation method using Span 80 and Span 60 as a surfactants. The prepared elastic liposomes were evaluated for entrapment efficiency, vesicle size, In vitro drug release. Results: The drug release profiles from different elastic liposomes-in-vehicle formulations were in agreement with the physicochemical properties of the formulations. The formulation prepared showed an average vesicle size 185.4nm. The amount of drug entrapped into the elastic liposomes formulations was determined. The entrapment efficiency was found to be 73.45±0.78 %. A good amount of drug was entrapped in the liposome formulations prepared. Based on different parameters formulations of batch TG2 was found to be the best formulations. Stability study was performed on the selected formulation TG2. When the regression coefficient values of were compared, it was observed that ‘r’ values of first order was maximum i.e. 0.993 hence indicating drug release from formulations was found to follow Korsmeyer Peppas model release kinetics Conclusion: These results indicate that elastic liposome can function as probable drug delivery systems to enhance transdermal permeation of metronidazole for treating the topical infections. Keywords: Metronidazole, Elastic liposomes, Topical administration, Skin infection

Novel Solid Dispersions of Naphthoquinone Using Different Polymers for Improvement of Antichagasic Activity

IVS320 (3a,10b-dihydro-1H-cyclopenta[b]naphtho[2,3-d]furan-5,10-dione) is a naphthoquinone that has low solubility in aqueous medium, a physical behavior that limits its biological activities, considering that compounds from this class have several activities. In this work, solid dispersions (SDs) prepared between IVS320 and polymers hydroxypropyl methylcellulose (HPMC), polyethylene glycol (PEG), and polyvinylpyrrolidone (PVP) were developed using physical mixture (PM), kneading (KN), and rotary evaporation (RE) methods. Dispersions were investigated using Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetry (TG), powder X-ray diffraction (PXRD), and scanning electron microscopy (SEM). In addition, in vitro antiparasitic activity in Trypanosoma cruzi Y strains was evaluated. Physical-chemical characterization demonstrated the formation of SDs through the interaction of IVS320 with polymeric matrices. SDs of IVS320-polymer presented a significant potentiation of antichagasic activity, with inhibitory growth around 62% (IVS320-HPMC/RE), 55% (IVS320-PEG/RE), and 85% (IVS320-PVP/RE), while pure IVS320 showed a value of 48% for the highest concentrations evaluated (50 µg/mL).

Concentration and Dilution of Ultrafine Bubbles in Water

Submicron-sized bubbles are now officially called ultrafine bubbles (UFBs) by the international standard. The concentration of UFBs is generally low (<109 particles/mL; <0.001 vol%) compared to other colloidal dispersions. To overcome this practical problem, we concentrated UFBs in ultrapure water prepared by a commercial UFB generator and quantified the effect of rotary evaporation of the dispersion media on the stability of UFBs. The UFB dispersions were characterized by a particle tracking analysis (PTA) instrument. The experimental results showed that the UFBs can be diluted and concentrated without changing the size distribution and there was little or no loss of UFBs. By using a rotary evaporator, UFB dispersions were about 30-fold concentrated and the resultant number concentration reached over 3 × 1010 particles/mL. Increasing the concentration of UFBs allowed for satisfactory dynamic light scattering (DLS) measurements. The differences among the three algorithms for analyzing the raw data, i.e., autocorrelation function, obtained by DLS are discussed, along with the characteristics of the particle size distribution derived from each algorithm.

The properties of Sweet Sorghum Syrup Produced by Combined Vacuum Falling Film and Rotary Evaporation

The combination of Vacuum Falling Film Evaporator(FFE) and Rotary Evaporator (RE) was conducted in producing sweet sorghum syrup. The aim of this research was to evaluate the performance of single FFE and combined FFE-RE on sorghum syrup concentration. Single FFE was studied at the temperature of 70, 80, and 90°C. The best single FFE treatment was continued by RE at 60, 70, and 80°C. Sweet sorghum that were concentrated using single FFE(90°C) and combined FFE(90°C)-RE(80°C) had the highest Total Soluble Solid(TSS) of 44.2°Brix and 87.53°Brix, also the acceptable lightness(L*) of 30.13 and 25.83 respectively. That combined FFE-RE produced sorghum syrup had the highest overall Hedonic score 3.34 within the taste parameter value of 2.89; color of 3,75; aroma of 3,29; and texture of 3.42. It was also accomplished with the redness(a*) of -2.11, yellowness(b*) of 5.13, turbidity of 387.66 NTU, viscosity of 2036.67cP, and reducing sugar of 52.54%.