Particle Preparation and Morphology Control with Mutual Diffusion Across Liquid-Liquid Interfaces

Abstract

Advanced functional materials require sophisticated control of particle characteristics. The bottom-up process has been extensively used to produce functional materials for controlling the particle properties of composite particles. We propose crystallization at liquid-liquid interfaces as an advanced particle formation method. This review introduces crystallization at a liquid-liquid interface based on several case studies used in various applications. Conventional crystallization has been generally used to produce crystals and particles with homogeneous particle properties. Liquid-liquid interfacial crystallization makes it possible to create composite particles with hetero-phase structures and interfaces. Liquid-liquid interfacial crystallization with an inkjet technique can control the droplet size accurately, and the shape and particle size distribution are successfully controlled in inorganic-organic composite particles. In addition, we succeed in creating organic-organic composite particles using the interfacial crystallization by an ultrasonic spray nozzle. The coating efficiency of organic particles on the particles is enhanced using the ultrasonic spray nozzle in comparison with anti-solvent crystallization. In this study, the fabrication of inorganic-organic composite particles using a coaxial tube reactor on the liquid-liquid interfacial crystallization is proven successful. These findings suggest that liquid-liquid interfacial crystallization is a promising means of efficiently producing composite particles because of their applicability to infusion in various processes.

New Case of Pharmaceutical Solid-State Forms: Several Novel Solvates/Polymorphs of Nilotinib and Their Phase Transformation Controls

“…Solid-state form control is extremely crucial in the preparation of pharmaceutical formulation. Various solid-state forms can commonly cause a wide variation in the characteristics of the drugs, such as melting point, , solubility, − dissolution rate, morphology, − stability, , hygroscopicity, compressibility, − and toxicity. , Neglecting the solid-state forms of the drug can lead to disastrous drug deterioration which results in large economic losses and also threatens the health of patients. Capsules containing ritonavir crystal form A, manufactured by Abbott Co., Ltd., underwent crystal transformation (from ritonavir form I to ritonavir form II).…”

Development of a nozzleless electrostatic atomization equipment for the mass production of encapsulated oil powders in the liquid phase

“…As electrostatic atomization progressed, the morphology of particles changed from a spherical to a rod‐like shape (Figure 7c,d). This was caused by the crystal growth of taurine precipitated at the planar interface between the oil and the aqueous phase (Kadota and Shirakawa, 2021). Considering the spherical particles containing oil in powders, the atomization time in the present equipment would be optimized to under 60 s. Figure 8 presents the comparison of particle‐size distribution for atomization times ranging from 30 to 60 s. The median particle size of the oil encapsulated in powder was 4.6 ± 1.78 μm at 30 s and 4.1 ± 1.78 μm at 60 s, indicating that these values were relatively uniform.…”

“…As electrostatic atomization progressed, the morphology of particles changed from a spherical to a rod-like shape (Figure 7c,d). This was caused by the crystal growth of taurine precipitated at the planar interface between the oil and the aqueous phase (Kadota and Shirakawa, 2021). Considering the spherical particles containing oil in powders, the atomization time in the present equipment would be optimized to under 60 s. Although oil contents are usually measured by gas chromatography measurements, FTIR technique for obtaining the oil contents was used because a small amount of particles was prepared at one operation in the present system.…”

High Performance Nickel Based Electrodes in State-of-the-Art Lithium-Ion Batteries: Morphological Perspectives

“…In addition to coprecipitation, it was reported that the sol-gel, spray drying technique, and spray pyrolysis techniques can be adapted to produce micro-spherical particles. For spray methods, spherical particles were formed by the formation of spherical droplets using a droplet maker, such as nebulizer and spray nozzles (Kadota and Shirakawa, 2021). The resulting droplets can be tuned easily.…”