Inherent challenges regarding the rheological characterization of slurries of elongated particles have necessitated the development of alternatives to standardized rheometers. These methods of measurement, and the associated advances in the quantification of shear and normal stress measurements, are described. Also, recent advances in modeling and predictive capabilities are summarized. During shearing flows, confinement substantially influences the orientation distribution of the particles; this change in the microstructure impacts the rheology, even as the smallest confining dimension exceeds seven particle lengths. The slow development of the orientation distributions renders additional difficulties in evaluating the rheology. Achievements of the measurement methods include a universal shear viscosity as a function of concentration for a wide range of particle lengths to diameters (aspect ratios). The jamming limit (divergence of the viscosity with concentration) of the suspensions has been also shown to scale differently than for spheres. More general dynamics of the suspensions and the additional needs for measurement improvements are discussed.
{"title":"Advances in the Rheological Characterization of Slurries of Elongated Particles","authors":"Saif Shaikh, Scott Strednak, Jason E. Butler","doi":"10.14356/KONA.2022009","DOIUrl":"https://doi.org/10.14356/KONA.2022009","url":null,"abstract":"Inherent challenges regarding the rheological characterization of slurries of elongated particles have necessitated the development of alternatives to standardized rheometers. These methods of measurement, and the associated advances in the quantification of shear and normal stress measurements, are described. Also, recent advances in modeling and predictive capabilities are summarized. During shearing flows, confinement substantially influences the orientation distribution of the particles; this change in the microstructure impacts the rheology, even as the smallest confining dimension exceeds seven particle lengths. The slow development of the orientation distributions renders additional difficulties in evaluating the rheology. Achievements of the measurement methods include a universal shear viscosity as a function of concentration for a wide range of particle lengths to diameters (aspect ratios). The jamming limit (divergence of the viscosity with concentration) of the suspensions has been also shown to scale differently than for spheres. More general dynamics of the suspensions and the additional needs for measurement improvements are discussed.","PeriodicalId":17828,"journal":{"name":"KONA Powder and Particle Journal","volume":"4 1","pages":""},"PeriodicalIF":4.1,"publicationDate":"2022-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88923892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A variety of dosage forms have been developed in order to achieve effective and safe drug delivery in topical or systemic drug administrations. In this review, formulation research and process issues related to a popular oral dosage form, the tablet, are introduced. Research on oral dosage forms, including orally disintegrating tablets (ODTs) and films (ODFs), which have recently been developed with an aim toward more patient-centric drug therapy, is also introduced. Another trend in recent drug therapy is an increase in the number of large bioactive molecules among the newly developed active pharmaceutical ingredients (APIs). To design dosage forms for these APIs, novel dosage form design and administration routes are required. For this purpose, we have tried to effectively use the polymer-coated liposomes in oral, pulmonary and ophthalmic administration. For example, suitable polymers were introduced for the design of specific administration routes, such as mucoadhesive liposomes for oral administration. The key point in these researches is the particle design for the component particles of final dosage forms, both in the case of coarse powder particle design for formulating solid dosage forms and in the case of colloidal particle design, such as the design of liposomes for peptide drug delivery.
{"title":"Contribution of Particle Design Research to the Development of Patient-Centric Dosage Forms","authors":"H. Takeuchi","doi":"10.14356/kona.2022017","DOIUrl":"https://doi.org/10.14356/kona.2022017","url":null,"abstract":"A variety of dosage forms have been developed in order to achieve effective and safe drug delivery in topical or systemic drug administrations. In this review, formulation research and process issues related to a popular oral dosage form, the tablet, are introduced. Research on oral dosage forms, including orally disintegrating tablets (ODTs) and films (ODFs), which have recently been developed with an aim toward more patient-centric drug therapy, is also introduced. Another trend in recent drug therapy is an increase in the number of large bioactive molecules among the newly developed active pharmaceutical ingredients (APIs). To design dosage forms for these APIs, novel dosage form design and administration routes are required. For this purpose, we have tried to effectively use the polymer-coated liposomes in oral, pulmonary and ophthalmic administration. For example, suitable polymers were introduced for the design of specific administration routes, such as mucoadhesive liposomes for oral administration. The key point in these researches is the particle design for the component particles of final dosage forms, both in the case of coarse powder particle design for formulating solid dosage forms and in the case of colloidal particle design, such as the design of liposomes for peptide drug delivery.","PeriodicalId":17828,"journal":{"name":"KONA Powder and Particle Journal","volume":"25 1","pages":""},"PeriodicalIF":4.1,"publicationDate":"2022-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80219202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Stephanie Hufnagel, Sawittree Sahakijpijarn, Chaeho Moon, Z. Cui, R. Williams
While the formulation of pharmaceuticals as liquids is common practice, powders are associated with enhanced stability, avoidance of the cold chain, lower dosing requirements, and more convenient administration. These are particularly critical for proteins, as they are expensive and complicated to manufacture. Powders also have improved aerosol properties for pulmonary delivery. Conventional techniques for formulating powders include spray-drying, shelf freeze-drying, spray freeze-drying, and spray freezing into liquid, but they produce powders with poor aerosol performance and/or activity due to suboptimal powder properties. Thin-film freezing (TFF) is a new cryogenic technique that can engineer highly porous, brittle, powder matrices with excellent aerosol performance properties and stability. Herein, we describe TFF in comparison to other cryogenic techniques. Physical properties of TFF powders such as morphology, moisture sorption, stability, solubility, and dissolution, as well as aerosol properties are discussed. In addition, factors that significantly affect the physical and aerosol properties of dry powders prepared by TFF, such as solids content, drug loading, solvent system, excipient, and dry powder delivery device, are analyzed. Finally, we provide evidence supporting the applicability of using TFF to prepare dry powder formulations of protein-based pharmaceuticals, enabling their cold chain-free storage as well as efficient pulmonary delivery.
{"title":"The Development of Thin-film Freezing and Its Application to Improve Delivery of Biologics as Dry Powder Aerosols","authors":"Stephanie Hufnagel, Sawittree Sahakijpijarn, Chaeho Moon, Z. Cui, R. Williams","doi":"10.14356/KONA.2022010","DOIUrl":"https://doi.org/10.14356/KONA.2022010","url":null,"abstract":"While the formulation of pharmaceuticals as liquids is common practice, powders are associated with enhanced stability, avoidance of the cold chain, lower dosing requirements, and more convenient administration. These are particularly critical for proteins, as they are expensive and complicated to manufacture. Powders also have improved aerosol properties for pulmonary delivery. Conventional techniques for formulating powders include spray-drying, shelf freeze-drying, spray freeze-drying, and spray freezing into liquid, but they produce powders with poor aerosol performance and/or activity due to suboptimal powder properties. Thin-film freezing (TFF) is a new cryogenic technique that can engineer highly porous, brittle, powder matrices with excellent aerosol performance properties and stability. Herein, we describe TFF in comparison to other cryogenic techniques. Physical properties of TFF powders such as morphology, moisture sorption, stability, solubility, and dissolution, as well as aerosol properties are discussed. In addition, factors that significantly affect the physical and aerosol properties of dry powders prepared by TFF, such as solids content, drug loading, solvent system, excipient, and dry powder delivery device, are analyzed. Finally, we provide evidence supporting the applicability of using TFF to prepare dry powder formulations of protein-based pharmaceuticals, enabling their cold chain-free storage as well as efficient pulmonary delivery.","PeriodicalId":17828,"journal":{"name":"KONA Powder and Particle Journal","volume":"11 1","pages":"2022010"},"PeriodicalIF":4.1,"publicationDate":"2022-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75417937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dockage and foreign material (DFM) distribution in grain silos is an important factor in managing stored grain. The DFM distribution in grain silos is dictated by the segregation mechanisms of DFM during grain loading. Loading grain into silos from a central spout is a special case of heap flows of granular materials. However, our understanding of heap flows is still evolving, and no models are currently available to predict the dockage and foreign material distribution in grain silos. Based on an extensive literature review, this paper identified the dominant mechanisms of DFM segregations during central spout filling in grain silos and main factors influencing DFM distribution. The DFM distribution patterns were characterized. The experimental methods for analyzing DFM segregations and distribution were also reviewed. The gaps of our knowledge on segregation mechanisms and factors influencing segregation were summarised and future research directions and challenges were discussed.
{"title":"A Review of Distribution and Segregation Mechanisms of Dockage and Foreign Materials in On-Farm Grain Silos for Central Spout Loading","authors":"F. Jian","doi":"10.14356/kona.2022014","DOIUrl":"https://doi.org/10.14356/kona.2022014","url":null,"abstract":"Dockage and foreign material (DFM) distribution in grain silos is an important factor in managing stored grain. The DFM distribution in grain silos is dictated by the segregation mechanisms of DFM during grain loading. Loading grain into silos from a central spout is a special case of heap flows of granular materials. However, our understanding of heap flows is still evolving, and no models are currently available to predict the dockage and foreign material distribution in grain silos. Based on an extensive literature review, this paper identified the dominant mechanisms of DFM segregations during central spout filling in grain silos and main factors influencing DFM distribution. The DFM distribution patterns were characterized. The experimental methods for analyzing DFM segregations and distribution were also reviewed. The gaps of our knowledge on segregation mechanisms and factors influencing segregation were summarised and future research directions and challenges were discussed.","PeriodicalId":17828,"journal":{"name":"KONA Powder and Particle Journal","volume":"76 1","pages":""},"PeriodicalIF":4.1,"publicationDate":"2022-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85562485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Understanding the flowability of cohesive powders at high temperature is of great importance for many industrial applications where these materials are handled at harsh thermal conditions. For instance, the Calcium-Looping (CaL) process, involving the transport, storage and fluidization of limestone powders at high temperature, is being considered nowadays as a promising technology for thermochemical energy storage (TCES) in concentrated solar power plants (CSP). In this context, the High Temperature Seville Powder Tester (HTSPT) is presented in this work as a useful tool to analyze how the flow behavior of cohesive powders changes with temperature. The manuscript reviews the main results obtained so far using this novel apparatus. The change of powder cohesiveness and therefore of powder flowability as depending on temperature, particle size, material properties and nanosilica surface coating is illustrated.
{"title":"The Sevilla Powder Tester: A Tool for Measuring the Flow Properties of Cohesive Powders at High Temperatures","authors":"R. Gannoun, J. Ebri, A. Pérez, J. Valverde","doi":"10.14356/KONA.2022008","DOIUrl":"https://doi.org/10.14356/KONA.2022008","url":null,"abstract":"Understanding the flowability of cohesive powders at high temperature is of great importance for many industrial applications where these materials are handled at harsh thermal conditions. For instance, the Calcium-Looping (CaL) process, involving the transport, storage and fluidization of limestone powders at high temperature, is being considered nowadays as a promising technology for thermochemical energy storage (TCES) in concentrated solar power plants (CSP). In this context, the High Temperature Seville Powder Tester (HTSPT) is presented in this work as a useful tool to analyze how the flow behavior of cohesive powders changes with temperature. The manuscript reviews the main results obtained so far using this novel apparatus. The change of powder cohesiveness and therefore of powder flowability as depending on temperature, particle size, material properties and nanosilica surface coating is illustrated.","PeriodicalId":17828,"journal":{"name":"KONA Powder and Particle Journal","volume":"47 1","pages":""},"PeriodicalIF":4.1,"publicationDate":"2022-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91255104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The aerosol particles play a significant role in the environment and human health. They are also increasingly used in medicine (drug carriers), preparation (nanocatalysts) and many other fields. For these applications, the particles have to possess unique properties which arise directly from their structure and topology. Indeed, the functionality of the nanostructure particle is defined through its application, like chromatography, sensors, microelectronics, catalysis, and others. That is the reason why people are more and more interested in manufacturing structured particles. The structured particles are the particles with well-defined topological structure. Examples of such particles are porous particles, hollow particles (with the empty space inside), or multi-component particles with the segregation of components in the particle structure. Such particles usually have very interesting features, e.g. porous particles have a significantly larger surface area than the simple spherical particles with similar volume. The present paper contains a comprehensive review of the numerical simulation methods of the formation of highly ordered structured particles. The most important methods will be described in detail and their fields of application (with specific examples), advantages, limitations and information about their accuracy will be given.
{"title":"Numerical Modelling of Formation of Highly Ordered Structured Micro- and Nanoparticles – A Review","authors":"J. Gac","doi":"10.14356/kona.2022019","DOIUrl":"https://doi.org/10.14356/kona.2022019","url":null,"abstract":"The aerosol particles play a significant role in the environment and human health. They are also increasingly used in medicine (drug carriers), preparation (nanocatalysts) and many other fields. For these applications, the particles have to possess unique properties which arise directly from their structure and topology. Indeed, the functionality of the nanostructure particle is defined through its application, like chromatography, sensors, microelectronics, catalysis, and others. That is the reason why people are more and more interested in manufacturing structured particles. The structured particles are the particles with well-defined topological structure. Examples of such particles are porous particles, hollow particles (with the empty space inside), or multi-component particles with the segregation of components in the particle structure. Such particles usually have very interesting features, e.g. porous particles have a significantly larger surface area than the simple spherical particles with similar volume. The present paper contains a comprehensive review of the numerical simulation methods of the formation of highly ordered structured particles. The most important methods will be described in detail and their fields of application (with specific examples), advantages, limitations and information about their accuracy will be given.","PeriodicalId":17828,"journal":{"name":"KONA Powder and Particle Journal","volume":"23 1","pages":""},"PeriodicalIF":4.1,"publicationDate":"2022-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82632229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Moe Tanaka, Ayaka Ochi, Aiko Sasai, Hiroyuki Tsujimoto, H. Kobara, Hiromitsu Yamamoto, A. Wakisaka
Microspheres composed of poly (lactic-co-glycolic acid) (PLGA) were formed in liquid droplets using the electrospray technique. The structure of the microspheres was controlled by changing the electric voltage of the electrospray. PLGA microspheres with porous structures and micro-sized nanocomposite particles comprising PLGA nanosphere aggregates were formed at 5.0–7.0 kV and 2.5–3.5 kV, respectively. The structural change was related to the extent of evaporation of the solvent from the droplets during their flight. When the evaporation was completed in the relatively small droplets, the microspheres with porous structures were formed in the droplets. To study the mechanism, we observed the effects of the electric voltage of the electrospray, PLGA concentration, flight distance of the droplets, and molecular weight of PLGA on the structure of the PLGA particles. The novelty of this study is the analysis of the size and structure of the PLGA microparticles, which were controlled by the electrospray technique. Therefore, this research has important implications for the structural design and preparation of nanocomposite particles.
{"title":"Biodegradable PLGA Microsphere Formation Mechanisms in Electrosprayed Liquid Droplets","authors":"Moe Tanaka, Ayaka Ochi, Aiko Sasai, Hiroyuki Tsujimoto, H. Kobara, Hiromitsu Yamamoto, A. Wakisaka","doi":"10.14356/kona.2022018","DOIUrl":"https://doi.org/10.14356/kona.2022018","url":null,"abstract":"Microspheres composed of poly (lactic-co-glycolic acid) (PLGA) were formed in liquid droplets using the electrospray technique. The structure of the microspheres was controlled by changing the electric voltage of the electrospray. PLGA microspheres with porous structures and micro-sized nanocomposite particles comprising PLGA nanosphere aggregates were formed at 5.0–7.0 kV and 2.5–3.5 kV, respectively. The structural change was related to the extent of evaporation of the solvent from the droplets during their flight. When the evaporation was completed in the relatively small droplets, the microspheres with porous structures were formed in the droplets. To study the mechanism, we observed the effects of the electric voltage of the electrospray, PLGA concentration, flight distance of the droplets, and molecular weight of PLGA on the structure of the PLGA particles. The novelty of this study is the analysis of the size and structure of the PLGA microparticles, which were controlled by the electrospray technique. Therefore, this research has important implications for the structural design and preparation of nanocomposite particles.","PeriodicalId":17828,"journal":{"name":"KONA Powder and Particle Journal","volume":"43 1","pages":""},"PeriodicalIF":4.1,"publicationDate":"2022-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90212093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Messa, Qi Yang, M. Rasteiro, P. Faia, V. Matoušek, Rui C. Silva, F. Garcia
{"title":"Computational Fluid Dynamic Modelling of Fully-Suspended Slurry Flows in Horizontal Pipes with Different Solids Concentrations","authors":"G. Messa, Qi Yang, M. Rasteiro, P. Faia, V. Matoušek, Rui C. Silva, F. Garcia","doi":"10.14356/kona.2023008","DOIUrl":"https://doi.org/10.14356/kona.2023008","url":null,"abstract":"","PeriodicalId":17828,"journal":{"name":"KONA Powder and Particle Journal","volume":"3 1","pages":""},"PeriodicalIF":4.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88758345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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