scholarly journals Polyelectrolyte Nanoparticles of Amphiphilic Chitosan/Pectin from Banana Peel as Potential Carrier System of Hydrophobic Molecules

Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2109
Author(s):  
Paula A. Méndez ◽  
Betty L. López
Keyword(s):  
Particle Size ◽  
Nile Red ◽  
Banana Peel ◽  
Loading Capacity ◽  
Mass Ratio ◽  
Carrier System ◽  
Acid Type ◽  
Hydrophobic Molecule ◽  
Acidic Conditions ◽  
Banana Wastes

In this study, pectins were extracted from banana wastes Musa paradisiaca under different acidic conditions, obtaining pectins with different degrees of esterification (DE) depending on the acid type and pH. The formation of the polyelectrolyte nanoparticles was evaluated according to the DE of the pectin, the mass ratio of the polymers of pectin to amphiphilic chitosan (AmCh), and their concentration. The properties of the polyelectrolyte nanoparticles were evaluated at different pH and temperatures. The pectin with 24.3% DE formed polyelectrolyte nanoparticles through the electrostatic interaction with AmCh, which was evidenced by changes in the zeta potential and particle size. The study of mass ratio AmCh:Pectin, to get a stable system, showed that it must be at least equal (1:1), or AmCh must be in higher proportion (6:1, 50:1, 100:1), and the polymers concentration must be 1 mg/mL. The study of the temperature effect showed that, when the temperature increases, the particle size decreases, and the pH study showed a stable particle size for the polyelectrolyte nanoparticles in the range of pH 5–6. Nile Red (NR), a hydrophobic molecule, was encapsulated in the polyelectrolyte nanoparticles with a loading capacity of 1.8% and an encapsulation efficiency of 80%.

scholarly journals Supramolecular Nanofibers from Collagen-Mimetic Peptides Bearing Various Aromatic Groups at N-Termini via Hierarchical Self-Assembly

2021 ◽  
Vol 22 (9) ◽  
pp. 4533
Author(s):  
Tomoyuki Koga ◽  
Shinya Kingetsu ◽  
Nobuyuki Higashi
Keyword(s):  
Self Assembly ◽  
Triple Helix ◽  
Wavelength Conversion ◽  
Nile Red ◽  
Tem Analysis ◽  
Mimetic Peptides ◽  
Collagen Mimetic Peptides ◽  
Potential Applications ◽  
Hydrophobic Molecule ◽  
Emission Behavior

Self-assembly of artificial peptides has been widely studied for constructing nanostructured materials, with numerous potential applications in the nanobiotechnology field. Herein, we report the synthesis and hierarchical self-assembly of collagen-mimetic peptides (CMPs) bearing various aromatic groups at the N-termini, including 2-naphthyl, 1-naphtyl, anthracenyl, and pyrenyl groups, into nanofibers. The CMPs (R-(GPO)n: n > 4) formed a triple helix structure in water at 4 °C, as confirmed via CD analyses, and their conformations were more stable with increasing hydrophobicity of the terminal aromatic group and peptide chain length. The resulting pre-organized triple helical CMPs showed diverse self-assembly into highly ordered nanofibers, reflecting their slight differences in hydrophobic/hydrophilic balance and configuration of aromatic templates. TEM analysis demonstrated that 2Np-CMPn (n = 6 and 7) and Py-CMP6 provided well-developed natural collagen-like nanofibers and An-CMPn (n = 5–7) self-assembled into rod-like micelle fibers. On the other hand, 2Np-CMP5 and 1Np-CMP6 were unable to form nanofibers under the same conditions. Furthermore, the Py-CMP6 nanofiber was found to encapsulate a guest hydrophobic molecule, Nile red, and exhibited unique emission behavior based on the specific nanostructure. In addition to the ability of CMPs to bind small molecules, their controlled self-assembly enables their versatile utilization in drug delivery and wavelength-conversion nanomaterials.

Preparation and Characterization of Hexadecane Microcapsule Phase Change Materials by In Situ Polymerization

2013 ◽  
Vol 815 ◽  
pp. 367-370 ◽  
Author(s):  
Xiao Qiu Song ◽  
Yue Xia Li ◽  
Jing Wen Wang
Keyword(s):  
Particle Size ◽  
Phase Change ◽  
Phase Change Materials ◽  
In Situ Polymerization ◽  
Urea Formaldehyde ◽  
Agitation Speed ◽  
Urea Formaldehyde Resin ◽  
Formaldehyde Resin ◽  
Mass Ratio

Hexadecane microcapsule phase change materials were prepared by the in-situ polymerization method using hexadecane as core materials, urea-formaldehyde resin and urea-formaldehyde resin modified with melamine as shell materials respectively. Effect of melamine on the properties of microcapsules was studied by FTIR, biomicroscopy (UBM), TGA and HPLC. The influences of system concentration, agitation speed and mass ratio of wall to core were also investigated. The results indicated that hexadecane was successfully coated by the two types of shell materials. The addition of melamine into the urea-formaldehyde resin microcapsule reduced microcapsule particle size and microencapsulation efficiency. The influences of factors such as system concentration, agitation speed and mass ratio of wall to core to different wall materials microcapsules presented different variety trends of the microcapsule particle size.

scholarly journals Ex-vivo Ex-Vivo Absorption Study of a Novel Dabigatran Etexilate Loaded Nanostructured Lipid Carrier Using Non-Everted Intestinal Sac Model

2019 ◽  
Vol 28 (2) ◽  
pp. 37-45
Author(s):  
Haithem N Abed ◽  
Ahmed A. Hussein
Keyword(s):  
Particle Size ◽  
Oleic Acid ◽  
Zeta Potential ◽  
Oral Absorption ◽  
Ex Vivo ◽  
Dabigatran Etexilate ◽  
Entrapment Efficiency ◽  
Nanostructured Lipid Carrier ◽  
Loading Capacity ◽  
Intestinal Permeation

Abstract The purpose of our study was to develop Dabigatran Etexilate loaded nanostructured lipid carriers (DE-NLCs) using Glyceryl monostearate and Oleic acid as lipid matrix, and to estimate the potential of the developed delivery system to improve oral absorption of low bioavailability drug, different Oleic acid ratios effect on particle size, zeta potential, entrapment efficiency and loading capacity were studied, the optimized DE-NLCs shows a particle size within the nanorange, the zeta potential (ZP) was 33.81±0.73mV with drug entrapment efficiency (EE%) of  92.42±2.31% and a loading capacity (DL%) of 7.69±0.17%. about 92% of drug was released in 24hr in a controlled manner, the ex-vivo intestinal permeation study using the non-everted sac model shows four folds increment in the permeation of DE-NLCs compared to dabigatran etexilate suspension (DE-S).

Colloidal Silica/Poly(Methacrylsiloxane) Nanocomposite Particles: Synthesis, Characterization, and Application in Toners.

2014 ◽  
Vol 1663 ◽  
Author(s):  
Dmitry Fomitchev ◽  
Russell Lewis ◽  
Hairuo Tu ◽  
Li Cheng ◽  
Hajime Kambara ◽  
...  
Keyword(s):  
Particle Size ◽  
Colloidal Silica ◽  
Silica Particles ◽  
Laser Printer ◽  
Mass Ratio ◽  
One Pot ◽  
New Class ◽  
New Material ◽  
Hydrophobic Treatment ◽  
Hydrophobic Material

ABSTRACTWe report on a new class of materials for laser printer toner applications. These materials were prepared from methacrysilane-in-water emulsions stabilized with colloidal silica particles. In this elegant system, the colloidal silica particles reside at the water/oil interface helping to emulsify the oil droplet, self-organizing into a raspberry-like morphology. The emulsion formation is followed by free-radical polymerization, hydrophobic treatment, and drying steps. This one pot synthesis in water affords a hydrophobic material with a particle size in the range of 80 to 300 nm. The particle size could be fine-tuned by changing the oil-to-silica mass ratio or by using colloidal silica particles of different sizes. Results of material characterization by solid-state NMR, electron microscopy, and particle size measurements methods will be presented. Examples of possible extensions of the synthesis towards materials with methacrylsilane partially substituted with other methacrylates will be provided. Application of the new material in toners will be described as will the comparison of its performance with the incumbent material - hydrophobic colloidal silica.

scholarly journals Experimental and statistical study for leaching of niobium pentoxide from Pakistani ore

2018 ◽  
Vol 24 (1) ◽  
pp. 51-58 ◽  
Author(s):  
Muhammad Irfan ◽  
Muhammad Ahmad ◽  
Sadia Akhtar ◽  
Muhammad Khan ◽  
Muhammad Khan
Keyword(s):  
Particle Size ◽  
Reaction Temperature ◽  
Batch Reactor ◽  
Niobium Pentoxide ◽  
Mass Ratio ◽  
Separation And Purification ◽  
Separation Processes ◽  
Separation Science ◽  
Low Concentration ◽  
Environmentally Friendly Process

The growing demand for niobium pentoxide, based on its use in separation processes, established its prominent significance as a leading candidate in the field of separation science and technology. This study reports the extraction of niobium pentoxide from pyrochlore ore occurring in Sillai Patai, KPK, Pakistan. It is difficult to recover niobium pentoxide from Pakistani ore due to its low concentration. Niobium pentoxide is an important material used in manufacturing industries for different purposes. Most of the commercially employed extraction processes are associated with serious environmental impacts and are not efficient in extracting niobium pentoxide from low concentration pyrochlore. Alkali potash has been used for separation and purification of niobium pentoxide because it is efficient and an environmentally friendly process. The leaching of niobium pentoxide is carried out in a batch reactor using alkali potash as a leachant. Various process parameters, including ore particle size, reaction temperature, reaction time and alkali to ore mass ratio, were examined statistically during the leaching process. It was observed that reaction temperature and ore particle size were more significant compared to other parameters. The maximum percent recovery of niobium pentoxide (95%) was obtained at 280?C in 90 min, while keeping the ore particle size 44 ?m and alkali to ore mass ratio of 7:1.

Numerical Study on Mechanism and Parameters Optimization of Temporary Plugging by Particles in Wellbore

2021 ◽  
pp. 1-16
Author(s):  
Tao Zhang ◽  
Ming Li ◽  
Jianchun Guo ◽  
Haoran Gou ◽  
Kefan Mu
Keyword(s):  
Particle Size ◽  
Numerical Study ◽  
Optimal Operation ◽  
Parameters Optimization ◽  
Mass Ratio ◽  
Stimulated Reservoir Volume ◽  
Reservoir Volume ◽  
Pump Rate ◽  
Single Well ◽  
Operation Parameters

Summary The temporary plugging by particles in the wellbore can open new perforation clusters and increase stimulated reservoir volume, but the temporary plugging process of particles is not clear. Therefore, in this paper, we take an ultradeep well in the Tarim Basin as the research object and establish a numerical model based on the coupled computational fluid dynamics-discrete element technology (CFD-DEM) approach, which accurately describes the movement process and mechanism of the temporary plugging particles in the wellbore. Furthermore, the influence of flow rate, concentration of injected particles, and the injected mass ratio of particle size on the temporary plugging effect were studied, respectively. In addition, based on the results of the orthogonal experimental analysis, we obtained the pump rate as the primary factor affecting the effect of temporary plugging, and we recommended the optimal operation parameters for temporary plugging by particles in the field: The pump rate is 2 m3/min, the concentration of the injected temporary plugging particles is 20%, and the ratio of the mass of the injected temporary plugging particles with particle size 1 to 5 mm to the mass of the temporary plugging particles with particle size 5 to 10 mm is 3:1. Finally, a single well that had implemented temporary plugging by particles was used to verify the recommended optimal temporary plugging operation parameters. The research results of this paper provide important guidance and suggestions for the design of temporary plugging schemes on the field.

scholarly journals BIODEGRADABLE POLYMER: A NOVEL PHARMACEUTICAL CARRIER FOR SUSTAINED RELEASE OF METRONIDAZOLE

2017 ◽  
Vol 10 (10) ◽  
pp. 136
Author(s):  
Gayathri Hariharan ◽  
Priyanka Sinha
Keyword(s):  
Particle Size ◽  
Drug Release ◽  
Sustained Release ◽  
Biodegradable Polymer ◽  
Drug Loading ◽  
Cross Linking ◽  
Loading Capacity ◽  
Flow Properties ◽  
Chitosan Microspheres

Objective: To optimize and evaluate the formulation of metronidazole (MT)-loaded chitosan microspheres and to investigate the efficiency of biodegradable polymer in developing sustained release formulation of MT to prolong the action of drug.Methods: MT microspheres were prepared using emulsion cross-linking method. Polymer-drug compatibility study was done using Fourier transform infrared. Physical characteristics were evaluated by particle size,SEM, flow properties etc. In vitro studies for evaluating drug release for MT-loaded chitosan microspheres were done by dissolution study.Results: Particle size of the formulated microspheres was found to be within the range of 110-130 μm. Flow properties of F1-F7 such as angle of repose, bulk density, and tapped density were found to be within limits. Drug entrapment efficiency was found to be better for all the formulations within the range of 74.82-84.32% w/w. Drug loading capacity was found to be in the range of 56-83.2% w/v. In vitro drug release was found to be in the range of 81.32-96.23% w/v.Conclusion: In spite of all the above results, we conclude that F5 formulation was optimized depending on the data obtained from the drug loading capacity and percentage drug release studies. F5 formulation is formulated with drug-polymer ratio 1:2 with 1% of di octyl sodium sulfo succinate and 8 ml of glutaraldehyde as a cross-linking agent.

Preparation and Research of Oil in Water Microemulsion

2020 ◽  
Vol 1001 ◽  
pp. 110-114
Author(s):  
Xiao Qi Chen ◽  
Meng Meng Zhou ◽  
Zheng Zheng Wang ◽  
Hai Jun Zhou ◽  
Shu Lan Yang ◽  
...  
Keyword(s):  
Particle Size ◽  
Constant Temperature ◽  
Polydispersity Index ◽  
Stable System ◽  
Mass Ratio ◽  
Drop Method ◽  
Mean Particle Size ◽  
Oil In Water ◽  
The Mean ◽  
The Stability

A series of oil in water (O/W) microemulsions were prepared through drop by drop method at constant temperature, taking Span80/Tween80 as a composite emulsifying system and Macol-52 as oil phase. Effects of the mass ratio of composite emulsifying system and oil/emulsifier ratio on the particle size were studied. Finally, the best technological conditions were selected and the stability of the microemulsion was also researched. Results showed that the most suitable Span80/Tween80 mass ratio was 1:1 and the oil/emulsifier ratio is 1:1. Under this condition, the mean particle size of the o/w microemulsion was 71.1 nm and the polydispersity index was 0.151. Moreover, the microemulsion maintain a bright and uniform stable system after 20minutes’ centrifugation at the speed of 4000r/min and the particle size increased slightly.

Development of Adsorbent from Banana Peel for Wastewater Treatment

2012 ◽  
Vol 248 ◽  
pp. 310-315 ◽  
Author(s):  
Jimoh Abdulfatai ◽  
Abdulkareem Ambali Saka ◽  
Ayo Samuel Afolabi ◽  
Onazi Micheal
Keyword(s):  
Particle Size ◽  
Contact Time ◽  
Industrial Effluent ◽  
Oxygen Demand ◽  
Environmental Water ◽  
Sorption Process ◽  
Zinc Ion ◽  
Banana Peel ◽  
Chromium Ion ◽  
Effects Of Ph

This study investigated the development and application of banana peel for the remediation of heavy metals (Pb, Zn and Cr). Batch experimental processes as well as conditions that might influence the sorption of the metals were investigated. These conditions include effects of pH, contact time, adsorbent dose, and particle size. The applicability of the sorption process was tested on wastewater. The adsorbent activated with 0.5 M H2SO4 showed the highest percentage removal of chromium ion (88.9 %) at a pH of 6. It has been found that particle size has no effect on the removal of zinc ion and it has also been found that the removal efficiency of lead and chromium ion decreased with increase in contact time and particle size. Also, it can be seen from the results that untreated banana peel waste increases the biochemical oxygen demand (BOD) and chemical oxygen demand (COD) values of wastewater. The results from the optimized method revealed the applicability of the method to environmental water samples. This study therefore confirms that banana peel is a promising adsorbent for the removal of chromium from industrial effluent.

Heat Resistance of Alicyclobacillus acidoterrestris Spores as Affected by Various pH Values and Organic Acids‡

1998 ◽  
Vol 61 (1) ◽  
pp. 41-46 ◽  
Author(s):  
APRIL J. PONTIUS ◽  
JOHN E. RUSHING ◽  
PEGGY M. FOEGEDING
Keyword(s):  
Heat Resistance ◽  
Fruit Juice ◽  
Ion Concentration ◽  
Thermal Processes ◽  
Alicyclobacillus Acidoterrestris ◽  
Hydrogen Ion Concentration ◽  
Ph Values ◽  
Acid Type ◽  
Acidic Conditions ◽  
D Values

Alicyclobacillus acidoterrestris, a thermoacidophilic sporeformer, has caused spoilage of fruit juices which had been treated with thermal processes intended to commercially sterilize the juice. The objective of this research was to document the effect of pH, acid, and temperature on the heat resistance of spores of three fruit-juice isolates of A. acidoterrestris. The thermal resistance of spores of A. acidoterrestris strains VF, WAC, and IP were studied in a model fruit-juice system composed of 12% glucose and 30 mM of either citric, malic, or tartaric acid, adjusted to selected pH values ranging from 2.8 to 4.0. Decimal reduction times (D values) and inactivation rates were determined. Spores of strains VF and WAC were similarly resistant to heat under acidic conditions, while strain IP spores were less resistant. In the range of pH 2.8 to 4.0, a statistically significant effect of hydrogen ion concentration on heat resistance was observed at lower temperatures, but not at the higher temperatures. For example, at 91 °C and pH 3.1 and 3.7, D values were 31.3 and 54.3 min, respectively, while at 97°C D values at pH 3.1 and 3.7 were 7.9 and 8.8 min, respectively. The type of acid did not significantly affect the heat resistance. The zD values ranged from 5.9 to 10°C, depending on the acid, pH, and the strain. The models generated from this research can be used to determine adequate thermal processes, accounting for the acid type, pH, and temperature, to destroy A. acidoterrestris spores in beverages, since this organism is able to survive the typical hot-fill and hold process (2 min at 88 to 96°C) currently used to process fruit juice.

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