Drug-Free Liposomes Containing Mannosylated Ligand for Liver-Targeting: Synthetic Optimization, Liposomal Preparation, and Bioactivity Evaluation

2021 ◽  
Vol 17 (12) ◽  
pp. 2455-2465
Author(s):  
Jing Chen ◽  
Yuan Lin ◽  
Min Wu ◽  
Chuangnan Li ◽  
Yimin Zhang ◽  
...  
Keyword(s):  
Average Particle Size ◽  
Spherical Particles ◽  
Molar Ratio ◽  
Optimum Operating ◽  
Average Particle ◽  
Liver Targeting ◽  
Hepatic Diseases ◽  
Substrate Molar Ratio ◽  
Drug Free ◽  
Mannosylated Liposomes

This research was performed to optimize the enzymatic synthesis of mannosylated ligand with which to prepare mannosy-lated liposomes and investigate their bioactivity. Based on single-factor studies, lipase dose, substrate molar ratio (diester lauric diacid-cholesterol to mannose) and temperature were identified as significant parameters, and optimal reaction conditions were determined through response surface methodology (RSM) with central composite design. The optimum operating parameters, 61.23 mg of lipase, a substrate molar ratio of 5.36, and 56.64 °C temperature offered a predicted yield (71.11%) which was consistent with the actual yield (69.08%). Drug-free mannosylated liposomes were prepared film-dispersion. The characterizations of these liposomes showed that mannosylated liposomes were well-dispersible spherical particles with an average particle size of 142.3 nm, the polydispersity index of 0.16, and a zeta potential of −19.8 mV. Pyrogen examination, hemolytic studies and cytotoxicity assays revealed no substantial safety concern for drug-free mannosylated liposomes. Cellular uptake efficiency of mannosylated liposomes by HepG2 cells was significantly higher than that of unmodified liposomes, demonstrating that mannosylated ligands have a positive effect on liver targeting. Overall, mannosylated liposomes could be active drug delivery system for combatting the therapy of hepatic diseases.

Modified Polyol-Mediated Synthesis of Doped TiO2 Nanoparticles as the Photoanode in Dye Solar Cells (DSCs)

2014 ◽  
Vol 925 ◽  
pp. 575-579
Author(s):  
Sattar Bashardoust ◽  
Muti Mohamed Norani ◽  
Boon Hoong Ong ◽  
Siti Nur Azella Zaine
Keyword(s):  
Crystal Structure ◽  
Solar Cells ◽  
Lattice Structure ◽  
Average Particle Size ◽  
Spherical Particles ◽  
Hydroxyl Group ◽  
Molar Ratio ◽  
Average Particle ◽  
X Ray ◽  
Dye Solar Cells

Synthesis of nanoscale TiO2exhibiting specific properties of electron or ion conductivity is critical to improve the performance of dye solar cells (DSC). This paper presents the modified polyol-mediated synthesis of doped TiO2nanoparticles. TiO2samples were doped with cobalt (Co) and nickel (Ni) and the effects of calcination temperature (550 °C and 650 °C) on the crystallinity of pure samples were investigated. X-ray diffraction (XRD) analysis was used to determine the effect of dopant in lattice structure. The morphology and Crystal structure of TiO2samples and their chemical analysis was conducted using scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectrometer respectively. Results show agglomeration of spherical particles in all doped samples. Crystal structure in the doped samples reveals modified phases and major crystal phase identical to anatase. It is observed that the molar ratio of water to metal can control the nucleation and growth and prevents significant agglomeration of nanoparticles. More effective doping was recorded for samples with 0.5 % concentration. Effective hydroxyl group is detected in both 0.5% Ni and Co promising good photocatalytic material. SEM images of 0.2% Ni-doped sample shows smallest average particle size.

Fe3O4 Magnetic Preparation by Bauxite Ore Washing Fine Mud

2014 ◽  
Vol 1010-1012 ◽  
pp. 961-965
Author(s):  
Jian Qiang Xiao ◽  
Guo Wei He ◽  
Yan Jin Hu
Keyword(s):  
Particle Size ◽  
Aging Time ◽  
Average Particle Size ◽  
Xrd Analysis ◽  
Test Methods ◽  
Raw Material ◽  
Molar Ratio ◽  
Average Particle ◽  
Experimental Conditions ◽  
Particle Size Analyzer

Bauxite waste sludge as a raw material, the use of reverse chemical coprecipitation synthesize Fe3O4. Researching temperature, precipitation concentration, aging time and Fe2+/Fe3+ molar ratio effect on the particle size, morphology. Optimal experimental conditions: temperature 70 °C, the precipitant NaOH mass ratio of 10%, aging time 3h, Fe2+/Fe3+ molar ratio of 2:3. Test methods using a laser particle size analyzer, XRD analysis of the products were characterized, the product is Fe3O4, the average particle size of 0.11mm.

Сrystalline structure and dielectric properties of ceramic materials based on AgNbO3

2020 ◽  
Vol 63 (7) ◽  
pp. 75-78
Author(s):  
Polina A. Bezborodova ◽  
◽  
Elena M. Filonenko ◽  
Kseniya R. Erager ◽  
Anatoly V. Butakov ◽  
...  
Keyword(s):  
Rietveld Method ◽  
Average Particle Size ◽  
Ceramic Materials ◽  
Analysis Data ◽  
Molar Ratio ◽  
Average Particle ◽  
Dielectric Parameters ◽  
Low Frequencies ◽  
X Ray ◽  
Substitution Degree

Using the data of qualitative X-ray phase analysis, it was shown that in a wide concentration range at 1223 K compounds based on silver niobate are formed in the condition of the heterovalent substitution of tungsten(VI) ions for niobium(V) ions. These compounds are isomorphic to a perovskite-type structure. Microprobe analysis data allows to determine the homogeneity of the analyzed samples and the correspondence of their experimental compositions to the theoretical ones for the formula Ag1-xNb1-xWxO3. Using the data of X-ray diffraction analysis (Rietveld method) in the Crystallography Data Analysis Software – GSAS, the crystal structure of the obtained compounds was refined. The surface morphology of samples having been obtained at 1373 K was investigated by scanning electron microscopy (SEM). It was shown that with an increase of Nb5+ to W6+ substitution degree for Ag1-xNb1-xWxO3 ceramic samples in the range of the (0.2≤x≤0.8) molar ratio, the average particle size for the studied compositions grows from 1.3 to 5.2 μm, respectively. For the obtained ceramic compounds based on silver niobate with a perovskite-like structure (tetragonal distortion), the temperature-frequency dependences of dielectric parameters in the range 300-900 K were studied. It was found that samples slowly cooled from 1373 K are characterized by low values of (ε ~ 10) and loss (tgδ ~ 0.004 at f = 1 kHz) at room temperature. The ceramics obtained are characterized by relatively high values of dielectric permittivity ε at low frequencies and/or high temperatures. The dielectric parameters of the obtained ceramics are similar to the characteristics of so-called "colossal" dielectric constant materials. The revealed features of the dielectric characteristics of quenched ceramics apparently result from Maxwell-Wagner relaxation at intercrystalline contacts.

scholarly journals Photocatalytic degradation of chlortetracycline hydrochloride in marine aquaculture wastewater under visible light irradiation with CuO/ZnO

2019 ◽  
Vol 80 (7) ◽  
pp. 1249-1256 ◽  
Author(s):  
Jinghua Liu ◽  
Xiaocai Yu ◽  
Liping Wang ◽  
Meicen Guo ◽  
Wanting Zhu ◽  
...  
Keyword(s):  
Visible Light ◽  
Photocatalytic Degradation ◽  
Diffuse Reflectance Spectroscopy ◽  
Average Particle Size ◽  
Molar Ratio ◽  
Average Particle ◽  
Marine Aquaculture ◽  
Aquaculture Wastewater ◽  
Co Precipitation ◽  
The Cost

Abstract A CuO/ZnO photocatalyst nanocomposite was successfully prepared by co-precipitation and characterized by investigating its chemical and physical properties by X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, UV-vis diffuse reflectance spectroscopy and photoluminescence spectroscopy. The average particle size of CuO/ZnO composite was found to be around 80 nm. The degradation of chlortetracycline hydrochloride pollutants in marine aquaculture wastewater using ZnO and CuO/ZnO was compared and it was found that CuO/ZnO nanocomposite is more efficient than ZnO. The effects of external factors on the photocatalytic effectiveness of nanocomposite were investigated under visible light. Also, the photocatalytic conditions for the degradation of chlortetracycline hydrochloride by the nanocomposite were optimized. Based on both ability and efficiency of degradation, and on the cost and availability, 10:2 molar ratio of Zn2+/Cu2+ and 0.7 g/L nanocomposite, was found to be optimal, in which case the average photocatalytic degradation rate of chlortetracycline hydrochloride reached 91.10%.

Low Temperature Hydrothermal Synthesis of Nanophase BaTiO3 and BaFe12O19 Powders

1996 ◽  
Vol 457 ◽  
Author(s):  
Fatih Dogan ◽  
Shawn O'rourke ◽  
Mao-Xu Qian ◽  
Mehmet Sarikaya
Keyword(s):  
Particle Size ◽  
Hydrothermal Reaction ◽  
Average Particle Size ◽  
Reaction Times ◽  
Nanocrystalline Powders ◽  
Molar Ratio ◽  
Average Particle ◽  
Hydrothermal Conditions ◽  
Processing Variables ◽  
Xrd And Tem

ABSTRACTNanocrystalline powders with an average particle size of 50 nm has been synthesized in two materials systems under hydrothermal conditions below 100°C. Processing variables, such as temperature, concentration and molar ratio of reactants and reaction time were optimized to obtain particles of reduced size and stoichiometric compositions. Hydrothermal reaction takes place between Ba(OH)2 solution and titanium/iron precursors in sealed polyethylene bottles in the BaTiO3 and BaFe12O19 systems, respectively. While crystalline BaTiO3 forms relatively fast within a few hours, formation of fully crystalline and stoichiometric BaFei20i9 require considerably longer reaction times up to several weeks and strongly dependent on the Ba:Fe ratio of the precursors. The structural and compositional evaluation of the nanophase powders were studied by XRD and TEM techniques.

Synthesis of Fe2O3/C Nanocomposite Using Microwave Assisted Calcination Method

2014 ◽  
Vol 896 ◽  
pp. 100-103 ◽  
Author(s):  
Anggi Puspita Swardhani ◽  
Ferry Iskandar ◽  
Abdullah Mikrajuddin ◽  
Khairurrijal
Keyword(s):  
Crystallite Size ◽  
Average Particle Size ◽  
Molar Ratio ◽  
Average Particle ◽  
X Ray ◽  
Molar Ratios ◽  
Microwave Assisted ◽  
Chloride Hexahydrate ◽  
Calcination Method ◽  
Scherrer Method

Fe2O3/C nanocomposites were successfully synthesized using microwave assisted calcination method. Ferric (III) chloride hexahydrate (FeCl36H2O), sodium hydroxide (NaOH), and dextrose monohydrate (C6H12O6H2O) were used as precursors. A microwave oven of 2.445 GHz with a power of 600 W for 20 minutes was employed during the syntheses. Calcination was performed in a simple furnace at 350 °C for 30 min. The molar ratio of C:Fe is the only process parameter. From Scanning Electron Microscope images, the average particle size were 199 nm and 74 nm for the samples with molar ratio of C:Fe of 1:2 and 1:1, respectively. X-ray diffractometer spectra showed that the obtained samples have γ-Fe2O3 (maghemite) crystal structure. Using the Scherrer method, the crystallite size were 61.7, 58.8, 52.5, and 48.8 nm for the samples with the molar ratios of C:Fe of 1:3, 1:2, 1:1, and 2:1, respectively. It means that the crystallite size of the nanocomposite decreases with the increase of the molar ratio of carbon to iron (C:Fe). The Brunauer-Emmett-Teller characterization showed that the surface area as high as 255.6 m2/g is achieved by of the Fe2O3/C nanocomposite with the molar ratio of C:Fe of 1:1.

scholarly journals Preparation, Characterization, and In Vivo Pharmacokinetic Study of the Supercritical Fluid-Processed Liposomal Amphotericin B

Pharmaceutics ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 589 ◽  
Author(s):  
Chang-baek Lim ◽  
Sharif Md Abuzar ◽  
Pankaj Ranjan Karn ◽  
Wonkyung Cho ◽  
Hee Jun Park ◽  
...  
Keyword(s):  
Particle Size ◽  
Amphotericin B ◽  
Supercritical Fluid ◽  
Liposomal Amphotericin ◽  
Average Particle Size ◽  
Spherical Particles ◽  
Liposomal Amphotericin B ◽  
Average Particle ◽  
In Vivo Pharmacokinetics

Here, we aimed to prepare and optimize liposomal amphotericin B (AmB) while using the supercritical fluid of carbon dioxide (SCF-CO2) method and investigate the characteristics and pharmacokinetics of the SCF-CO2-processed liposomal AmB. Liposomes containing phospholipids, ascorbic acid (vit C), and cholesterol were prepared by the SCF-CO2 method at an optimized pressure and temperature; conventional liposomes were also prepared using the thin film hydration method and then compared with the SCF-CO2-processed-liposomes. The optimized formulation was evaluated by in vitro hemolysis tests on rat erythrocytes and in vivo pharmacokinetics after intravenous administration to Sprague-Dawley rats and compared with a marketed AmB micellar formulation, Fungizone®, and a liposomal formulation, AmBisome®. The results of the characterization studies demonstrated that the SCF-CO2-processed-liposomes were spherical particles with an average particle size of 137 nm (after homogenization) and drug encapsulation efficiency (EE) was about 90%. After freeze-drying, mean particle size, EE, and zeta potential were not significantly changed. The stability study of the liposomes showed that liposomal AmB that was prepared by the SCF method was stable over time. In vivo pharmacokinetics revealed that the SCF-CO2-processed-liposomes were bioequivalent to AmBisome®; the hemolytic test depicted less hematotoxicity than Fungizone®. Therefore, this method could serve as a potential alternative for preparing liposomal AmB for industrial applications.

Preparation of Nano-TiO2 Using a Sol-Gel Process Mediated in Reverse Microemulsion Combined with a Solvent Thermal Technique

2011 ◽  
Vol 287-290 ◽  
pp. 1731-1734 ◽  
Author(s):  
Han Sheng Li ◽  
Hang Xu ◽  
Shi Ying Wang ◽  
Ya Lin Pan ◽  
Qin Wu ◽  
...  
Keyword(s):  
Sol Gel ◽  
Average Particle Size ◽  
High Photocatalytic Activity ◽  
Reverse Microemulsion ◽  
Molar Ratio ◽  
Average Particle ◽  
Anatase Structure ◽  
Sol Gel Process ◽  
Triton X ◽  
Thermal Technique

Anatase nano-titania (nano-TiO2) was prepared by using a sol-gel process mediated in reverse microemulsion combined with a solvent thermal technique. The results show that the anatase structure appears in the calcination temperature range of 400-510°C, while the transformation of anatase into rutile takes place above 510°C. The average particle size (dP) of the nano-TiO2 increases with the rise of water/Triton X-100 molar ratio (ω) but decreases with the rise of acetyl acetone/n-TBT molar ratio (p) and n-hexanol/Triton X-100 molar ratio (m). The obtained TiO2 particles with a small size have high photocatalytic activity.

Near Infrared Tunable Gold Nanoparticles for Low Power Laser Ablation of Esophageal Adenocarcinoma

2012 ◽  
Vol 1416 ◽  
Author(s):  
Guandong Zhang ◽  
Jacek Jasinski ◽  
Dhruvinkumar Patel ◽  
Kurtis James ◽  
Xinghua Sun ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Low Power ◽  
Esophageal Adenocarcinoma ◽  
Near Infrared ◽  
Average Particle Size ◽  
Sodium Thiosulfate ◽  
Molar Ratio ◽  
Average Particle ◽  
Chloroauric Acid ◽  
Nir Absorption

ABSTRACTGold nanoparticles (GNPs) with precisely controlled near infrared (NIR) absorption were synthesized by one-step reaction of chloroauric acid and sodium thiosulfate. The NIR absorption wavelengths and average particle size increase with increasing molar ratio of HAuCl4/Na2S2O3. The as-synthesized GNPs consist of different shape and size, including small spherical gold colloids and larger non-spherical gold crystals. The GNPs with good chemical and optical stability only form in a suitable range of the HAuCl4/Na2S2O3 molar ratio. High molar ratio of HAuCl4/Na2S2O3 reduces GNPs stability due to Ostwald ripening. Chitosan coating improves particle stability and allows these GNPs effective ablation for esophageal adenocarcinoma under low power NIR laser radiation.

Synthesis and Characterization of Nanocrystalline Anatase by Microwave Hydrothermal Method

2012 ◽  
Vol 500 ◽  
pp. 104-107
Author(s):  
Zhi Qin Chen ◽  
Xiang Liang Chen ◽  
Shu Juan Zhang ◽  
Jun Xi Hu ◽  
Wen Kui Li
Keyword(s):  
Hydrothermal Method ◽  
Average Particle Size ◽  
Butyl Alcohol ◽  
Molar Ratio ◽  
Tetrabutyl Titanate ◽  
Average Particle ◽  
Synthesis Conditions ◽  
Microwave Hydrothermal ◽  
Microwave Hydrothermal Method

Uniform nanocrystalline pure anatase has been synthesized and characterized using tetrabutyl titanate aqueous solution as starting precursors by microwave hydrothermal method. The influences of synthesis conditions (reaction time and temperature) on the formation, crystal phase and crystallite size of TiO2has been investigated. A mixture solution of tetrabutyl titanate and normal butyl alcohol in 1:4 molar ratio is processed in a microwave hydrothermal autoclave at low temperature 120°C for different durations, at 200°C for 20 min to precipitate titania powders, respectively. It was revealed that uniformly dispersed and granulous single phase anatase prepared at 120°C for 180 min with the average particle size of 10 nm was formed by means of XRD and TEM.

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