scholarly journals Importance of Mesoporous Silica Particle Size in the Stabilization of Amorphous Pharmaceuticals—The Case of Simvastatin

Pharmaceutics ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 384
Author(s):  
Justyna Knapik-Kowalczuk ◽  
Daniel Kramarczyk ◽  
Krzysztof Chmiel ◽  
Jana Romanova ◽  
Kohsaku Kawakami ◽  
...  
Keyword(s):  
Particle Size ◽  
Mesoporous Silica ◽  
Particle Sizes ◽  
Scanning Calorimetry ◽  
Broadband Dielectric Spectroscopy ◽  
Amorphous Pharmaceuticals ◽  
Stabilization Effect ◽  
Crystallization Tendency ◽  
Mesoporous Silica Particle

In this paper, the role of mesoporous silica (MS) particle size in the stabilization of amorphous simvastatin (SVT) is revealed. For inhibiting recrystallization of the supercooled drug, the two MS materials (Syloid® XDP 3050 and Syloid® 244 FP) were employed. The crystallization tendency of SVT alone and in mixture with the MS materials was investigated by Differential Scanning Calorimetry (DSC) and Broadband Dielectric Spectroscopy (BDS). Neither confinement of the SVT molecules inside the MS pores nor molecular interactions between functional groups of the SVT molecules and the surface of the stabilizing excipient could explain the observed stabilization effect. The stabilization effect might be correlated with diffusion length of the SVT molecules in the MS materials that depended on the particle size. Moreover, MS materials possessing different particle sizes could offer free spaces with different sizes, which might influence crystal growth of SVT. All of these factors must be considered when mesoporous materials are used for stabilizing pharmaceutical glasses.

scholarly journals The Evaluation of Meloxicam Nanocrystals by Oral Administration with Different Particle Sizes

Molecules ◽  
2022 ◽  
Vol 27 (2) ◽  
pp. 421
Author(s):  
Yao Yu ◽  
Yang Tian ◽  
Hui Zhang ◽  
Qingxian Jia ◽  
Xuejun Chen ◽  
...  
Keyword(s):  
Particle Size ◽  
Water Solubility ◽  
Cell Model ◽  
Particle Sizes ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Laser Scattering ◽  
Transport Studies ◽  
Transmission Electron ◽  
Transmission And Absorption

Meloxicam (MLX) is a non-steroidal anti-inflammatory drug used to treat rheumatoid arthritis and osteoarthritis. However, its poor water solubility limits the dissolution process and influences absorption. In order to solve this problem and improve its bioavailability, we prepared it in nanocrystals with three different particle sizes to improve solubility and compare the differences between various particle sizes. The nanocrystal particle sizes were studied through dynamic light scattering (DLS) and laser scattering (LS). Transmission electron microscopy (TEM) was used to characterize the morphology of nanocrystals. The sizes of meloxicam-nanocrystals-A (MLX-NCs-A), meloxicam-nanocrystals-B (MLX-NCs-B), and meloxicam-nanocrystals-C (MLX-NCs-C) were 3.262 ± 0.016 μm, 460.2 ± 9.5 nm, and 204.9 ± 2.8 nm, respectively. Molecular simulation was used to explore the distribution and interaction energy of MLX molecules and stabilizer molecules in water. The results of differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD) proved that the crystalline state did not change in the preparation process. Transport studies of the Caco-2 cell model indicated that the cumulative degree of transport would increase as the particle size decreased. Additionally, plasma concentration–time curves showed that the AUC0–∞ of MLX-NCs-C were 3.58- and 2.92-fold greater than those of MLX-NCs-A and MLX-NCs-B, respectively. These results indicate that preparing MLX in nanocrystals can effectively improve the bioavailability, and the particle size of nanocrystals is an important factor in transmission and absorption.

scholarly journals Removal of the commercial reactive dye Procion Blue MX-7RX from real textile wastewater using the synthesized Fe2O3 nanoparticles at different particle sizes as a source of Fenton's reagent

2019 ◽  
Vol 1 (4) ◽  
pp. 1362-1371 ◽  
Author(s):  
Maha A. Tony ◽  
Shehab A. Mansour
Keyword(s):  
Particle Size ◽  
Textile Wastewater ◽  
Reactive Dye ◽  
Particle Sizes ◽  
Fe2o3 Nanoparticles ◽  
Dyeing Wastewater ◽  
Textile Dyeing ◽  
Fenton System ◽  
Textile Dyeing Wastewater

The aim of the present study was to signify the role of the particle size of an iron source in the photo-Fenton system for textile dyeing wastewater oxidation.

scholarly journals Particle size and fraction of wheat bran influence short-chain fatty acid productionin vitro

2009 ◽  
Vol 102 (10) ◽  
pp. 1404-1407 ◽  
Author(s):  
Maria L. Stewart ◽  
Joanne L. Slavin
Keyword(s):  
Particle Size ◽  
Wheat Bran ◽  
Small Particle ◽  
Large Particle ◽  
Short Chain Fatty Acid ◽  
Whole Grains ◽  
Particle Sizes ◽  
Fine Particle Size

Whole grains are associated with decreased risk of chronic disease and decreased risk of obesity. Several mechanisms may be involved including SCFA production via fibre fermentation in the colon. The aim of the present study was to evaluate the role of wheat bran particle size (large/coarsev.small/fine) and wheat bran fraction (whole branv.aleuronev.aleurone by-product) in SCFA production using a batchin vitrofermentation system with human faecal inoculum. Five samples were compared: large-particle bran, small-particle bran, aleurone, coarse by-product, fine by-product. Fine by-product produced the greatest SCFA concentrations. By-product (both coarse and fine) produced greater SCFA concentrations than bran (both large and small particle sizes). Aleurone produced SCFA concentrations similar to small-particle bran. The molar percentage of butyrate at 24 h was significantly greater for large-particle bran than the other samples. Small/fine particle size and by-product fraction of bran increased SCFA production compared with large/coarse particle size, and aleurone and whole bran. Bran characteristics and composition should be considered when manufacturing foods due to the diversity of physiological effects.

Effect of Ti Particle Size on Reaction Synthesis of Ti Aluminide

2012 ◽  
Vol 710 ◽  
pp. 314-319 ◽  
Author(s):  
Rohit Kumar Gupta ◽  
Bhanu Pant ◽  
Vijaya Agarwala ◽  
Parameshwar Prasad Sinha
Keyword(s):  
Particle Size ◽  
High Temperature ◽  
Titanium Aluminide ◽  
Reaction Synthesis ◽  
Particle Sizes ◽  
Minor Phase ◽  
Chemical Homogeneity ◽  
Major Phase ◽  
Ti Powder

Titanium aluminide intermetallic was made through reaction synthesis (RS) process using elemental powders. Pressure assisted synthesis was carried out at high temperature under vacuum. Ti powder with two different particle sizes (200μm and 30μm average) were used in RS. Synthesized blocks were homogenized and characterized for chemical homogeneity, density, phase formation and microstructure evolution. Products near to theoretical density have been obtained with uniform chemistry after homogenization. Al3Ti as a major phase along with TiAl as minor phase was confirmed after RS and TiAl along with Ti3Al was observed after homogenization. Homogenization cycle was found to be different for the alloys made through different Ti particle sizes. Significant role of Ti particle size has been observed in this pressure assisted RS process.

scholarly journals Size Effect of Mesoporous Silica Nanoparticles on Pesticide Loading, Release, and Delivery in Cucumber Plants

2021 ◽  
Vol 11 (2) ◽  
pp. 575
Author(s):  
Yongbing Xu ◽  
Chunli Xu ◽  
Qiliang Huang ◽  
Lidong Cao ◽  
Feifei Teng ◽  
...  
Keyword(s):  
Particle Size ◽  
Mesoporous Silica ◽  
Size Effect ◽  
Silica Nanoparticles ◽  
Mesoporous Silica Nanoparticles ◽  
Research Work ◽  
Control Release ◽  
Carbon Quantum Dots ◽  
Particle Sizes ◽  
Effective Utilization

Mesoporous silica nanoparticles (MSN) are widely used as pesticide carriers to enhance their effective utilization, since it can promote the solubility and absorption of pesticides by plants. For plants, the particle size of pesticides influences their absorption and efficacy. Herein, is our research work of the size effect of MSN on the loading, release, and delivery behavior of pyraoxystrobin (Pyr) in cucumber plants. The well-ordered Pyr-loaded carbon quantum dots-MSN (Pyr@M) with sizes of 15, 100, and 200 nm were prepared. A comparative study among different particle sizes of Pyr@M was carried out on the aspects of control release performance, loading content, uptake, and transportation performance in cucumber plants. It was found that the loading content increased as the particle size increased. The nanoparticles as carriers increased the solubility of insoluble Pyr, but the nanoparticle size had no clear difference impact on the release rate. The efficiency of the cellular uptake strongly depended on the particle size. The smaller the MSN size, the easier it was to be absorbed and transmitted by cucumber plants. Compared to the free Pyr, the upward transportation rate of Pyr from Pyr@M in plant increased by 3.5 times. These findings provide new theoretical basis to design the MSN pesticide delivery system.

Influence of the Particle Size on Phase Transformation Temperatures of Ni-49at.%Ti Shape Memory Alloy Powders

2010 ◽  
Vol 660-661 ◽  
pp. 124-127
Author(s):  
George Carlos S. Anselmo ◽  
Walman Benício de Castro ◽  
Carlos José de Araújo
Keyword(s):  
Particle Size ◽  
Martensitic Transformation ◽  
Shape Memory ◽  
Particle Sizes ◽  
Gas Atomization ◽  
Scanning Calorimetry ◽  
Transformation Temperatures ◽  
Ni Alloys ◽  
Material Saving ◽  
Start Temperature

It is important to control the martensitic transformation start temperature (Ms) of Ti–Ni alloys because it determines the temperature range over which the shape memory effect and superelasticity appear. Powder metallurgy (PM) is known to provide the possibility of material-saving and automated fabrication of at least semi-finished products as well as net-shape components for NiTi alloys. In this study powder with different particle sizes was subjected by gas atomization. The evolution of the control the martensitic transformation start temperature (Ms) was studied by differential scanning calorimetry. The effect of the particle size of powders on the transformation temperatures behaviors was discussed.

Dispersity, mesoporous structure and particle size modulation of hollow mesoporous silica nanoparticles with excellent adsorption performance

2018 ◽  
Vol 47 (38) ◽  
pp. 13345-13352
Author(s):  
Guiju Tao ◽  
Wenjun He ◽  
Yu Wang ◽  
Fengping Yu ◽  
Junwei Ge ◽  
...  
Keyword(s):  
Particle Size ◽  
Mesoporous Silica ◽  
Silica Nanoparticles ◽  
Mesoporous Silica Nanoparticles ◽  
Mesoporous Structure ◽  
Particle Sizes ◽  
Adsorption Performance ◽  
Hollow Mesoporous Silica ◽  
Mesoporous Structures

Hollow mesoporous silica nanoparticles with different dispersities, mesoporous structures and particle sizes, and excellent adsorption performance have been systematically synthesized.

scholarly journals The Effect of Extender Particle Size on the Glass Transition Temperature of Model Epoxy Coatings

Polymers ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 196 ◽  
Author(s):  
Muhammad Ahsan Bashir ◽  
Martin Gjerde Jakobsen ◽  
Vivian Beate Farstad
Keyword(s):  
Particle Size ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Mechanical Analysis ◽  
Organic Coatings ◽  
Particle Sizes ◽  
Scanning Calorimetry ◽  
Epoxy Amine ◽  
Thermosetting Epoxy

Inorganic extenders are important constituents of 2K thermosetting epoxy-amine coatings and their physical properties play an important role in the final properties of the organic coatings. The effects of extender particle size and loading (i.e., the amount of extender in component A or in the total formulation) on the glass transition temperature (Tg) of model epoxy-amine coatings were studied in this work with differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). The obtained results show that the particle size and loading of feldspar particles (from 25 wt% to 70 wt%) do not influence the glass transition temperature of the model epoxy-amine coating significantly. In general, the smaller the particle size the lower the glass transition temperature of the coating but this depression in Tg seems negligible when seen relative to the change in extender particle size. Similar observations are reported for two model coatings having the same lamda (Λ) value but with silica of very different particle sizes (i.e., nanosilica and micron sized silica).

scholarly journals Surface Modification of PES Hollow Fiber Membranes using Iron Oxide Particles for Water Treatment Does Particle Size Really Matter?

2021 ◽  
Vol 17 (5) ◽  
pp. 621-635
Author(s):  
Nadiene Salleha Mohd Nawi ◽  
Lau Woei Jye ◽  
Norhaniza Yusof ◽  
Noresah Said ◽  
Ahmad Fauzi Ismail
Keyword(s):  
Particle Size ◽  
Surface Modification ◽  
Iron Oxide ◽  
Water Treatment ◽  
Polymeric Membranes ◽  
Particle Sizes ◽  
Particle Type ◽  
Iron Oxide Particles ◽  
Oxide Particles

Factors such as particle type and its loading have been previously studied in tailoring the efficiency of particles-modified polymeric membranes for water treatment. However, the role of particle sizes in membrane modification is often overlooked. 

scholarly journals Electrostatic Charges of Abrasive Powders: A Role of Particle Size and Humidity

Coatings ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1520
Author(s):  
Alexander Tkach ◽  
Miguel Garcez ◽  
Paula M. Vilarinho
Keyword(s):  
Particle Size ◽  
Electrostatic Charge ◽  
Industrial Applications ◽  
Dc Resistivity ◽  
Particle Sizes ◽  
Faraday Cup ◽  
Electrostatic Charges ◽  
Α Al2o3 ◽  
Coated Abrasives

Electrostatically coated abrasives have drawn vast attention in many industrial applications. Therefore, influence of humidity on the electrical properties of α-SiC and α-Al2O3 abrasive powders with three μm-range particle sizes are here investigated using electrostatic charge and DC resistivity analysis. From the three particle size ranges used, 15–16 μm, 60–63 μm and 153–156 μm, the intermediate one (60–63 μm) is found to be associated with the highest charge values, measured using a double Faraday cup method, as well as the highest resistivity for both materials. However, comparing SiC and Al2O3 powders, the latter ones present about twice larger charges in dry and normal humidity states accompanied by several orders of magnitude larger resistivity. Under humid conditions all the powders reveal diminishing charge and resistivity values.

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