scholarly journals Influences of Size and Amount of Colloidal Template and Droplet Diameter on the Formation of Porous-structured Hyaluronic Acid Particles

2017 ◽  
Vol 2 (2) ◽  
pp. 152 ◽  
Author(s):  
Asep Bayu Dani Nandiyanto ◽  
Kikuo Okuyama
Keyword(s):  
Hyaluronic Acid ◽  
Spray Drying ◽  
Droplet Diameter ◽  
Synthesis Process ◽  
Outer Diameter ◽  
Polystyrene Spheres ◽  
Templating Method ◽  
Porous Particles ◽  
Shaped Particle ◽  
Host Component

Combination of spray drying and templating method has been reported as one of the best method to produce porous pharmaceutical particles. However, current development reports have shown successful formation of porous particles with improper information on what mechanism occurs during the synthesis process and what process parameters involve the creation of particles with controllable pore structures and morphologies. In this report, influences of spray-drying parameters (i.e., size and amount of colloidal template, and droplet diameter) on porous particle fabrication were investigated. Hyaluronic acid (as a model of pharmaceutical drug host component) and polystyrene spheres (as a model of template) were used. The experimental results showed that the spray-drying parameters strongly influenced the external morphology (i.e., spherical and doughnut-shaped), particle outer diameter (from 300 to 2000 nm), and porous configuration (i.e., number of hole cavities and pore sizes (from 100 to 300 nm)) of particles. To qualitatively explain our synthesis strategies to get porous structure, the proposal of the particle formation mechanism was added.

Controllable Mesopore-size and Outer Diameter of Silica Nanoparticles Prepared by a Novel Water/Oil-Phase Technique

2009 ◽  
Vol 1220 ◽  
Author(s):  
Asep Bayu Dani Nandiyanto ◽  
Yutaka Kaihatsu ◽  
Ferry Iskandar ◽  
Kikuo Okuyama
Keyword(s):  
Mesoporous Silica ◽  
Pore Size ◽  
Self Assembly ◽  
Particle Diameter ◽  
Silica Particles ◽  
Spherical Particles ◽  
Outer Diameter ◽  
Ps Ii ◽  
Porous Particles ◽  
Process Compatibility

AbstractTunable pore size and outer particle diameter of spherical mesoporous silica particles in the nanometer range were successfully synthesized using a novel water/oil-phase synthesis technique. This method involves (i) simultaneous hydrolytic condensation of tetraorthosilicate to form silica and polymerization of styrene into polystyrene (PS), (ii) self-assembly nanocluster silica and nanocluster PS to form silica/PSL nanoparticle, and (iii) calcination process to remove organic components and to produce mesoporous silica particle. In this study, an amino acid (e.g. lysine) was utilized to catalyze and to maintain the silica formation due to its ability in covering prepared silica after reaction. Further, another advantage of this catalyst is more harmless than other catalysts (e.g. ammonia, N2H4). The result showed spherical particles with controllable pore size (from 4 to 15 nm) and outer diameter (from 20 to 80 nm) was produced. The ability to control pore size and outer diameter was drastically altered by adjusting the concentration of styrene and hydrophobic molecules, respectively. After the preparation of particle was understood clearly, the large-molecule-adsorption performance of the prepared porous particles was conducted. As expected, relatively large organic molecules (i.e. Rhodamine B) were well-absorbed in the prepared sample but not by the commercial non-porous particles. With this reason, the prepared mesoporous silica particles may be used efficiently in various applications, including electronic devices, sensors, pharmaceuticals, and environmentally sensitive pursuits, due to its harmless process, compatibility for bio-application, and excellent adsorption properties.

scholarly journals Ultrasonic application and spray drying during amorphous calcium phosphate synthesis

2019 ◽  
Vol 8 (4) ◽  
pp. 711-714
Keyword(s):  
Electron Microscopy ◽  
Particle Size ◽  
Calcium Phosphate ◽  
Spray Drying ◽  
Amorphous Calcium Phosphate ◽  
Calcium Phosphates ◽  
Calcium Content ◽  
Synthesis Process ◽  
Particle Sizes ◽  
Ultrasound Application

Hydroxyapatite, amorphous calcium phosphates, calcium triphosphate and calcium octaphosphate are the main components present in bones and teeth. Calcium phosphates are easily synthesized, playing an important role in regenerative medicine, being able to be used as bone implants. There are different ways of synthesizing phosphates, the most commonly used being wet chemical method. The objective of this work was to study the influence of the use of ultrasound and spray drying on the synthesis of amorphous calcium phosphate. Two synthetic variants were studied. One without ultrasound application and the other with ultrasound application. The samples obtained were characterized by X-ray diffraction, FTIR spectroscopy and scanning electron microscopy. The particle size by electron microscopy and the calcium content by atomic absorption was determined. The results showed that when spray drying is applied, particle sizes of less than 261 nm are obtained in the samples synthesized without ultrasound application, being less than 59 nm in the samples synthesized with ultrasound application. The statistical analysis by ANOVA showed significant differences between the particle sizes of the samples synthesized without ultrasound application and the samples synthesized by applying ultrasound. In both cases the particles were spherical. The results obtained show that the application of ultrasound during the synthesis process decreases the particle size, increasing the surface area, which favors the spray drying process.

scholarly journals Synthesis of Porous Particles by Electrospray-Assisted Self-Assembly for Water-Repellent or Photocatalytic Surfaces

2020 ◽  
Vol 58 (2) ◽  
pp. 112-124
Author(s):  
Young-Sang Cho ◽  
Younghyun Lee ◽  
Nahee Ku ◽  
Sugueun Ji ◽  
Young Seok Kim
Keyword(s):  
Porous Ceramic ◽  
Ambient Air ◽  
Water Repellent ◽  
Volatile Components ◽  
Coating Film ◽  
Water Contact ◽  
Ceramic Particles ◽  
Templating Method ◽  
Porous Particles ◽  
Polystyrene Nanospheres

In this study, an electrospray technique was used for the synthesis of macroporous ceramic particles, such as silica or titania, by a colloidal templating method. For this purpose, a suspension of polystyrene nanospheres was synthesized by dispersion polymerization for use as sacrificial templates. The feed solution containing a ceramic precursor and polymeric beads was injected through a metallic nozzle under a high electric field for nebulization of aerosol droplets as micro-reactors. Under ambient air conditions, the volatile components were evaporated from the droplets, and gelation of the precursor was completed simultaneously. The resulting supra-aggregates were then collected, and calcination was performed to form porous ceramic particles by removing the polymeric templates. As a demonstrative application, the porous particles of silica were deposited as a coating film for superhydrophobic surfaces with a high water contact angle larger than 150°. Furthermore, macroporous titania particles were used as photocatalytic particles in a wastewater system with first-order reaction kinetics.

Combustion syntheses for BaTi4O9 and PbxBa1–x Ti4O9

1996 ◽  
Vol 11 (1) ◽  
pp. 162-168 ◽  
Author(s):  
Zhimin Zhong ◽  
Patrick K. Gallagher
Keyword(s):  
Solid State ◽  
Low Temperature ◽  
Aqueous Solutions ◽  
Combustion Synthesis ◽  
Spray Drying ◽  
Single Phase ◽  
Metastable Phases ◽  
Solid State Synthesis ◽  
Synthesis Process ◽  
Spray Dried

BaTi4O9 and PbxBa1−x Ti4O9, where x is 0.1, 0.2, 0.3, 0.4, or 0.5, have been prepared by a combustion synthesis process. The process starts with spray drying aqueous solutions of Pb(NO3)2, Ba(NO3)2, TiO(NO3)2, and β-alanine with appropriate ratios. Combustion reactions occur when heating the spray-dried products to 300 °C, which convert them to BaTi4O9 and PbxBa1−xTi4O9 directly. PbxBa1−xTi4O9 (x ≧ 0.1) are low temperature, metastable phases and have not been reported before. Pb0.5Ba0.5Ti4O9 is unstable above 800 °C and cannot be sintered. All PbxBa1−xTi4O9 compositions will decompose by 1300 °C, the temperature for solid state synthesis of BaTi4O9. Single-phase PbxBa1−xTi4O9 (x = 0.1, 0.2, 0.3, 0.4), however, have been sintered at relatively lower temperatures.

scholarly journals Práškové částice pro plicní podání

2022 ◽  
Vol 116 (1) ◽  
pp. 28-34
Author(s):  
Jakub Karas ◽  
David Vetchý ◽  
Jan Gajdziok
Keyword(s):  
Drug Delivery ◽  
Present Article ◽  
Spray Drying ◽  
Active Ingredient ◽  
Active Substance ◽  
Porous Particles ◽  
Production Processes ◽  
Effective Option ◽  
Aerodynamic Parameters ◽  
Preparation And Evaluation

The deposition of a drug to its required destination is crucial for effective lung treatment. It is important to design a suitable formulation that delivers the active ingredient to the desired site and resists the natural cleansing mechanisms of the airways. Large porous particles used as active substance carriers appear to be the most effective option for lung drug delivery. The present article provides a basic overview of the mechanisms of deposition of dry inhalable powders and methods of their preparation and evaluation. Spray drying together with micronization and crystallization techniques are among the most used methods of preparation of the discussed particles. Besides, these techniques can be combined with other production processes (encapsulation, emulsification, etc.). The evaluation of the properties of particles suitable for pulmonary application is based on specific requirements for their density, porosity, shape, aerodynamic parameters, and deposition in the lungs, which can now be simulated on an accurate model of artificial lungs.

Overview of Enzyme Engineering Towards the Production of Hyaluronic Acid with Tailored Molecular Weight

2021 ◽  
Vol 23 ◽  
Author(s):  
Tahereh Ebrahimi ◽  
Kamran Hosseini ◽  
Hossein Ahangari ◽  
Pourya Gholizadeh ◽  
Vahideh Tarhriz
Keyword(s):  
Molecular Weight ◽  
Hyaluronic Acid ◽  
Critical Role ◽  
Biological Properties ◽  
Research Field ◽  
Enzyme Engineering ◽  
The Body ◽  
Synthesis Process ◽  
Hyaluronan Synthase ◽  
Wide Range

: Hyaluronic acid or hyaluronan (HA) is a natural biopolymer composed of D-glucuronic acid and N-acetylglucosamine units, distributed as a non-sulfated and anionic glycosaminoglycan in important tissues of the body, and is commercially and biologically important. Its biological properties are determined by the molecular weight and dispersity which are suitable for particular medical and cosmetic applications. The synthesis of well-defined and monodisperse HA is still a significant obstacle and an impressive research field for advanced medical applications. High polydispersity by bacterial fermentation, the lack of knowledge of the mechanism required to start and continue the synthesis process, increased cost of raw materials to produce HA, clarification and explanation of factors limiting synthesis in bacterial systems are among the important challenges of hyaluronic acid synthesis. Hyaluronan synthase plays a critical role in HA molecular mass by producing a wide range of HA involved in various biological processes. Hyaluronan biosynthesis has been considered extensively; however, the control of its size and weight during the synthesis process is poorly investigated. This review focuses on these uncharted biochemical details to obtain the uniform chain lengths of Hyaluronan by protein engineering and regulating the function of Hyaluronan synthase.

scholarly journals Template-assisted spray-drying method for the fabrication of porous particles with tunable structures

2019 ◽  
Vol 30 (12) ◽  
pp. 2908-2924 ◽  
Author(s):  
Asep Bayu Dani Nandiyanto ◽  
Takashi Ogi ◽  
Wei-Ning Wang ◽  
Leon Gradon ◽  
Kikuo Okuyama
Keyword(s):  
Spray Drying ◽  
Drying Method ◽  
Porous Particles

Preparation of macroporous SAPO-34 microspheres by a spray drying method using polystyrene spheres as hard template

2011 ◽  
Vol 37 (8) ◽  
pp. 949-959 ◽  
Author(s):  
Yuanlin Liu ◽  
Lingzhi Wang ◽  
Jinlong Zhang ◽  
Feng Chen ◽  
Masakazu Anpo
Keyword(s):  
Spray Drying ◽  
Drying Method ◽  
Polystyrene Spheres ◽  
Hard Template

scholarly journals Research on the mechanism of the influence of flooding on the killing of empty wells

2021 ◽  
Vol 11 (9) ◽  
pp. 3571-3598
Author(s):  
Jie Zhang ◽  
Zaipeng Zhao ◽  
Xin Li ◽  
Yundong Zheng ◽  
Cuinan Li ◽  
...  
Keyword(s):  
Surface Tension ◽  
Droplet Diameter ◽  
Drill Pipe ◽  
Outer Diameter ◽  
Fluid Viscosity ◽  
Replacement Method ◽  
Dynamic Replacement ◽  
Calculation Results ◽  
Casing Pressure ◽  
Pipe Joint

AbstractIn empty well killing, in order to save the time and cost of killing the well, the dynamic replacement method is often used to kill the well. The main problem of the dynamic replacement method for killing wells is how to avoid terrible working conditions caused by flooding, such as gas carrying fluid, killing fluid being brought to the wellhead. Based on the principle of flooding formation and the basic tenets of flooding correlation experiment and dynamic replacement method, this paper incorporates the kill fluid viscosity, surface tension, droplet diameter, inclination angle, drill pipe joint outer diameter, and drill pipe eccentricity into the calculation range and establishes a new mathematical model suitable for dynamic replacement kill. Based on the calculation results, the influencing factors of flooding are analyzed, and the following conclusions are drawn: the increase of dynamic viscosity, gas density in the well, casing pressure, well angle, the outside diameter of drill pipe, the outer diameter of drill pipe joint, and eccentricity of drill pipe can promote the occurrence of flooding; The increase of surface tension, well-killing fluid density, and casing inner diameter have an obstacle to flooding.

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