Effect of solvent type on preparation of ethyl cellulose microparticles by solvent evaporation method with double emulsion system using focused beam reflectance measurement

Abstract

The purpose of this study was to investigate the effect of solvent type on the solidification rate of ethyl cellulose (EC) microparticles and particle size/distribution of emulsion droplets/hardened microparticles during the solvent evaporation process using focused beam reflectance measurement (FBRM). EC microparticles were prepared with a water-in-oil-in-water solvent evaporation method using various solvents, including dichloromethane, dichloromethane-methanol (1:1), ethyl acetate and chloroform. The particle size/distribution of the emulsion droplets/hardened microparticles was monitored using FBRM. The morphology of EC microparticles was characterized using scanning electron microscopy (SEM). The transformation of the emulsion droplets into solid microparticles for all solvents occurred within the first 10-90 min. The square weighted mean chord length of EC microparticles prepared using chloroform was smallest, but the chord count was not the highest. The chord length distribution (CLD) measured by FBRM showed that a larger mean particle size gave longer CLD and a lower peak of particle number. SEM data revealed that the morphology of microparticles was influenced by the type of solvent. FBRM can be employed for online monitoring of the shift in the microparticle CLD and detect transformation of emulsion droplets into solid microparticles during the solvent evaporation process. The microparticle CLD and transformation process were strongly influenced by solvent type.

Antiplasmodial Activity of Methanolic Leaf Extract of Mangrove Plants against Plasmodium berghei

“…As the result, there was rendement value (1.8% w/w) of extract which been stored as the dried extract in the refrigerator at 4°C for further used. 9,14,15 Phytochemical screening…”

Microencapsulation of Macaranga gigantea Leaf Extracts: Production and Characterization

“…7,21 Solvent evaporation method has been widely and extensively used to prepare polymeric microparticles containing different drugs and in the development of modified release systems. 22,23 It is a rapid process that does not involve severe heat treatment; therefore, it is a suitable method to preserve biological products, including temperature sensitive products, without their degradation; it also allows for storage at room temperature. It is an instantaneous process where spherical and uniform samples can be obtained, and the process can be easily scaled up.…”

“…It is an instantaneous process where spherical and uniform samples can be obtained, and the process can be easily scaled up. [23][24][25][26] Thermal degradation, nutrient loss, and denaturation are minimal, allowing maximum retention of the active principles. Solvent evaporation method is a technique more economical than lyophilization (four to seven times less costly); it also allows coating, complex coacervation, and drying of two different feed solutions during the process.…”

“…A number of hydrophilic drugs like the peptide leuprolide acetate, a lutenizing hormone-releasing hormone-releasing hormone agonist, vaccines, proteins/peptides and conventional molecules have been successfully encapsulated by this method. 23,24,[30][31][32][33][34][35] Depending on the polymer used, microencapsulation may control organoleptic modifications and increase the solubility/dissolution rate of the product. A good encapsulating agent (wall material) should have emulsifying and film forming properties, display low hygroscopicity, have low viscosity at high solid contents, resistance to the gastrointestinal tract, be biodegradable, non-toxic, low-cost, bland in flavor/tasteless, soluble in aqueous solvents, and food-grade.…”

In Focus Emerging Polymer Technologies Summit (EPTS'16)

“…In addition, the Summit included many other keynote and invited speakers, and a raft of young and early career scientists' contributions that formed an integral part of the EPTS'16 scientific program. This In Focus comprises five papers . Unfortunately, many of the speakers did not elect to take advantage of this special In Focus, however, note that Professor Moad's plenary presentation (Co)polymerization of the conjugated diene monomers: butadiene, isoprene and chloroprene has already been published in Polymer International …”