Effects of lower alcohols on nanocomposite particles for inhalation prepared using O/W emulsion

2021 ◽  
pp. 1-10
Author(s):  
Issei Takeuchi ◽  
Yukie Kimura ◽  
Takehisa Nakajima ◽  
Kimiko Makino
Keyword(s):  
Fine Particle ◽  
Average Diameter ◽  
Continuous Phase ◽  
Dispersed Phase ◽  
Mixed Solution ◽  
Spray Dryer ◽  
Particle Fraction ◽  
Nanocomposite Particles ◽  
Lower Alcohol ◽  
Effect Of The Composition

BACKGROUND: Inhalable nanocomposite particles using O/W emulsions were studied. The effect of the composition of the dispersed phase on the nanoparticles in the nanocomposite particles was reported, however, the effect on the inhalation characteristics of nanocomposite particles has not been investigated. OBJECTIVE: The aim of this study was to study the effects of lower alcohols in the dispersed phase of O/W emulsions on inhalable nanocomposite particles. METHODS: Nanocomposite particles were prepared using a spray dryer from O/W emulsion. A mixed solution of dichloromethane and lower alcohols in which rifampicin (RFP) and poly(L-lactide-co-glycolide) were dissolved was used as a dispersed phase, and an aqueous solution in which arginine and leucine were dissolved was used as a continuous phase. RESULTS: We succeeded in preparing non-spherical nanocomposite particles with an average diameter of 9.01–10.91 μm. The results of the fine particle fraction (FPF) measurement showed that the higher the hydrophobicity of the lower alcohol mixed in the dispersed phase, the higher the FPF value. The FPF value of the nanocomposite particles was significantly increased by using ethanol and 1-propanol. CONCLUSIONS: The results were revealed that mixing 1-propanol with the dispersed phase increased the amount of RFP delivered to the lungs.

Phase Inversion in Two-Phase Liquid Systems

1992 ◽  
Vol 57 (7) ◽  
pp. 1419-1423
Author(s):  
Jindřich Weiss
Keyword(s):  
Interfacial Tension ◽  
Phase Inversion ◽  
Continuous Phase ◽  
Considerable Effect ◽  
Weak Dependence ◽  
Dispersed Phase ◽  
Two Phase ◽  
Liquid Systems ◽  
Phase Liquid

New data on critical holdups of dispersed phase were measured at which the phase inversion took place. The systems studied differed in the ratio of phase viscosities and interfacial tension. A weak dependence was found of critical holdups on the impeller revolutions and on the material contactor; on the contrary, a considerable effect of viscosity was found out as far as the viscosity of continuous phase exceeded that of dispersed phase.

Capillary pressure, osmotic pressure and bubble contact areas in foams

Soft Matter ◽  
2021 ◽  
Author(s):  
Reinhard Höhler ◽  
Jordan Seknagi ◽  
Andrew Kraynik
Keyword(s):  
Osmotic Pressure ◽  
Capillary Pressure ◽  
Continuous Phase ◽  
Dispersed Phase ◽  
Average Pressure ◽  
Contact Areas ◽  
The Difference

The capillary pressure of foams and emulsions is the difference between the average pressure in the dispersed phase and the pressure in the continuous phase.

Effect of Geometry on Droplet Generation in a Microfluidic T-Junction

2013 ◽  
Author(s):  
Katerina Loizou ◽  
Wim Thielemans ◽  
Buddhika N. Hewakandamby
Keyword(s):  
Aspect Ratio ◽  
Cross Section ◽  
Droplet Formation ◽  
Continuous Phase ◽  
Main Channel ◽  
Superficial Velocity ◽  
Droplet Generation ◽  
Dispersed Phase ◽  
Aspect Ratios ◽  
The Cross

The main aim of this study is to examine how the droplet formation in microfluidic T-junctions is influenced by the cross-section and aspect ratio of the microchannels. Several studies focusing on droplet formation in microfluidic devices have investigated the effect of geometry on droplet generation in terms of the ratio between the width of the main channel and the width of the side arm of the T-junction. However, the contribution of the aspect ratio and thus that of the cross-section on the mechanism of break up has not been examined thoroughly with most of the existing work performed in the squeezing regime. Two different microchannel geometries of varying aspect ratios are employed in an attempt to quantify the effect of the ratio between the width of the main channel and the height of the channel on droplet formation. As both height and width of microchannels affect the area on which shear stress acts deforming the dispersed phase fluid thread up to the limit of detaching a droplet, it is postulated that geometry and specifically cross-section of the main channel contribute on the droplet break-up mechanisms and should not be neglected. The above hypothesis is examined in detail, comparing the volume of generated microdroplets at constant flowrate ratios and superficial velocities of continuous phase in two microchannel systems of two different aspect ratios operating at dripping regime. High-speed imaging has been utilised to visualise and measure droplets formed at different flowrates corresponding to constant superficial velocities. Comparing volumes of generated droplets in the two geometries of area ratio near 1.5, a significant increase in volume is reported for the larger aspect ratio utilised, at all superficial velocities tested. As both superficial velocity of continuous phase and flowrate ratio are fixed, superficial velocity of dispersed phase varies. However this variation is not considered to be large enough to justify the significant increase in the droplet volume. Therefore it can be concluded that droplet generation is influenced by the aspect ratio and thus the cross-section of the main channel and its effect should not be depreciated. The paper will present supporting evidence in detail and a comparison of the findings with the existing theories which are mainly focused on the squeezing regime.

scholarly journals Liquid–Liquid Flows with Non-Newtonian Dispersed Phase in a T-Junction Microchannel

Micromachines ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 335
Author(s):  
Anna Yagodnitsyna ◽  
Alexander Kovalev ◽  
Artur Bilsky
Keyword(s):  
Flow Pattern ◽  
Dynamic Viscosity ◽  
Slug Flow ◽  
Shear Thinning ◽  
Continuous Phase ◽  
Immiscible Liquid ◽  
Dispersed Phase ◽  
Effective Dynamic ◽  
Liquid Flows ◽  
Shear Thinning Fluid

Immiscible liquid–liquid flows in microchannels are used extensively in various chemical and biological lab-on-a-chip systems when it is very important to predict the expected flow pattern for a variety of fluids and channel geometries. Commonly, biological and other complex liquids express non-Newtonian properties in a dispersed phase. Features and behavior of such systems are not clear to date. In this paper, immiscible liquid–liquid flow in a T-shaped microchannel was studied by means of high-speed visualization, with an aim to reveal the shear-thinning effect on the flow patterns and slug-flow features. Three shear-thinning and three Newtonian fluids were used as dispersed phases, while Newtonian castor oil was a continuous phase. For the first time, the influence of the non-Newtonian dispersed phase on the transition from segmented to continuous flow is shown and quantitatively described. Flow-pattern maps were constructed using nondimensional complex We0.4·Oh0.6 depicting similarity in the continuous-to-segmented flow transition line. Using available experimental data, the proposed nondimensional complex is shown to be effectively applied for flow-pattern map construction when the continuous phase exhibits non-Newtonian properties as well. The models to evaluate an effective dynamic viscosity of a shear-thinning fluid are discussed. The most appropriate model of average-shear-rate estimation based on bulk velocity was chosen and applied to evaluate an effective dynamic viscosity of a shear-thinning fluid. For a slug flow, it was found that in the case of shear-thinning dispersed phase at low flow rates of both phases, a jetting regime of slug formation was established, leading to a dramatic increase in slug length.

Formation of Two-Phase Multiple Emulsions by Inclusion of Continuous Phase into Dispersed Phase

Langmuir ◽  
2002 ◽  
Vol 18 (20) ◽  
pp. 7334-7340 ◽  
Author(s):  
Jong-Moon Lee ◽  
Kyung-Hee Lim ◽  
Duane H. Smith
Keyword(s):  
Continuous Phase ◽  
Dispersed Phase ◽  
Two Phase ◽  
Multiple Emulsions

Effect of Shear and Water Cut on Phase Inversion and Droplet Size Distribution in Oil–Water Flow

2018 ◽  
Vol 141 (3) ◽  
Author(s):  
Mo Zhang ◽  
Ramin Dabirian ◽  
Ram S. Mohan ◽  
Ovadia Shoham
Keyword(s):  
Size Distribution ◽  
Droplet Size ◽  
Phase Inversion ◽  
Droplet Size Distribution ◽  
Continuous Phase ◽  
Dispersed Phase ◽  
Water Emulsion ◽  
Inversion Region ◽  
Oil Water ◽  
Water Cut

Oil–water dispersed flow occurs commonly in the petroleum industry during the production and transportation of crudes. Phase inversion occurs when the dispersed phase grows into the continuous phase and the continuous phase becomes the dispersed phase caused by changes in the composition, interfacial properties, and other factors. Production equipment, such as pumps and chokes, generates shear in oil–water mixture flow, which has a strong effect on phase inversion phenomena. The objective of this paper is to investigate the effects of shear intensity and water cut (WC) on the phase inversion region and also the droplet size distribution. A state-of-the-art closed-loop two phase (oil–water) flow facility including a multipass gear pump and a differential dielectric sensor (DDS) is used to identify the phase inversion region. Also, the facility utilizes an in-line droplet size analyzer (a high speed camera), to record real-time videos of oil–water emulsion to determine the droplet size distribution. The experimental data for phase inversion confirm that as shear intensity increases, the phase inversion occurs at relatively higher dispersed phase fractions. Also the data show that oil-in-water emulsion requires larger dispersed phase volumetric fraction for phase inversion as compared with that of water-in-oil emulsion under the same shear intensity conditions. Experiments for droplet size distribution confirm that larger droplets are obtained for the water continuous phase, and increasing the dispersed phase volume fraction leads to the creation of larger droplets.

Influence of Morphology on Mechanical Properties under the Combined Use of SEBS and EOr as Elastomer in PP/Elastomer/Filler Ternary Composites

2011 ◽  
Vol 19 (9) ◽  
pp. 725-732
Author(s):  
Shigeki Hikasa ◽  
Kazuya Nagata ◽  
Yoshinobu Nakamura
Keyword(s):  
Mechanical Properties ◽  
Impact Strength ◽  
Triblock Copolymer ◽  
Continuous Phase ◽  
Dispersed Phase ◽  
Impact Properties ◽  
Combined Use ◽  
Poly Ethylene ◽  
Almost All ◽  
The Impact

The influences of combined elastomers on impact properties and morphology of polypropylene (PP)/elastomer/CaCO3 ternary composites were investigated. In the case that polystyrene- block-poly(ethylene-butene)- block-polystyrene triblock copolymer (SEBS) and poly(ethylene- co-octene) (EOR) were used as elastomers, a sea-island structure consisting of EOR dispersed phase and SEBS continuous phase was formed. The elastomer and the CaCO3 particles were separately dispersed in PP matrix. In the case that carboxylated SEBS (C-SEBS) and EOR were used, the C-SEBS particles were dispersed in the EOR particles. Almost all of the CaCO3 particles were dispersed in the PP matrix, although some of the CaCO3 particles were dispersed in the C-SEBS/EOR combined particles. Impact strength improved with an increase of incorporated CaCO3 particles. The effect of elastomer on the impact strength was SEBS ≥ SEBS/EOR > EOR = C-SEBS/EOR > C-SEBS. The morphology formed by elastomer and CaCO3 particles strongly affected the impact properties of the ternary composites.

scholarly journals Aerosolization Performance of Jet Nebulizers and Biopharmaceutical Aspects

Pharmaceutics ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 406 ◽  
Author(s):  
Greta Adorni ◽  
Gerrit Seifert ◽  
Francesca Buttini ◽  
Gaia Colombo ◽  
Luciano A. Stecanella ◽  
...  
Keyword(s):  
Fine Particle ◽  
Drug Product ◽  
Patient Characteristics ◽  
Relevant Information ◽  
Fine Particle Fraction ◽  
Particle Fraction ◽  
Dose Delivery ◽  
Aerosol Emission ◽  
Jet Nebulizers

In this work, 13 jet nebulizers, some of which in different configurations, were investigated in order to identify the biopharmaceutical constraints related to the quality attributes of the medicinal products, which affect their safety, efficiency, compliance, and effectiveness. The aerosolization parameters, including the aerosol output, aerosol output rate, mass median aerodynamic diameter, and fine particle fraction, were determined according to the European Standard EN 13544-1, using sodium fluoride as a reference formulation. A comparison between the aerosol output nebulization time and the fine particle fraction displayed a correlation between the aerosol quality and the nebulization rate. Indeed, the quality of the nebulization significantly increased when the rate of aerosol emission was reduced. Moreover, the performance of the nebulizers was analyzed in terms of respirable delivered dose and respirable dose delivery rate, which characterize nebulization as the rate and amount of respirable product that could be deposited into the lungs. Depending on which of these two latter parameters was used, the nebulizers showed different performances. The differences, in terms of the rate and amount of delivered aerosol, could provide relevant information for the appropriate choice of nebulizer as a function of drug product, therapy, and patient characteristics.

Ordering Transitions of Semifluorinated Diblock Copolymers

2008 ◽  
Vol 8 (9) ◽  
pp. 4864-4868 ◽  
Author(s):  
Min Young Lee ◽  
Seung Ho Kim ◽  
Jong Tae Kim ◽  
Sok Won Kim ◽  
Kwon Taek Lim
Keyword(s):  
Diblock Copolymers ◽  
Average Diameter ◽  
Continuous Phase ◽  
Tem Analysis ◽  
Ordering Transitions ◽  
Cylindrical Domains ◽  
Spherical Structures ◽  
Spherical Domains ◽  
Different Shapes ◽  
Chain Lengths

A series of diblock copolymers consisting of a hydrophilic polyethylene oxide (PEO) and a hydrophobic poly(1H,1H-dihydroperfluorooctyl methacrylate) (PDHFOMA) block were synthesized with different chain lengths for application to self-assembled nanopatterning structures. The morphology of poly(DHFOMA5k-b-EO5k), poly(DHFOMA10k-b-EO10k), and poly(DHFOMA20k-b-EO20k) spin cast from micellar solution in chloroform at room temperature were spherical with average diameter of 12 nm, 17 nm and 26 nm, respectively by TEM analysis. The spherical structures were reorganized to different shapes with thermodynamically stable morphologies upon annealing above glass transition temperature (Tg). PDHFOMA block domains changed to well ordered cylindrical domains, inversed continuous phase, and large composite spherical domains for 5 k, 10 k, and 20 k block copolymer, respectively.

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