Preparation of PLGA Nanoparticles by Milling Spongelike PLGA Microspheres

Abstract

Currently, emulsification-templated nanoencapsulation techniques (e.g., nanoprecipitation) have been most frequently used to prepare poly-d,l-lactide-co-glycolide (PLGA) nanoparticles. This study aimed to explore a new top-down process to produce PLGA nanoparticles. The fundamental strategy was to prepare spongelike PLGA microspheres with a highly porous texture and then crush them into submicron-sized particles via wet milling. Therefore, an ethyl formate-based ammonolysis method was developed to encapsulate progesterone into porous PLGA microspheres. Compared to a conventional solvent evaporation process, the ammonolysis technique helped reduce the tendency of drug crystallization and improved drug encapsulation efficiency accordingly (solvent evaporation, 27.6 ± 4.6%; ammonolysis, 65.1 ± 1.7%). Wet milling was performed on the highly porous microspheres with a D50 of 64.8 μm under various milling conditions. The size of the grinding medium was the most crucial factor for our wet milling. Milling using smaller zirconium oxide beads (0.3~1 mm) was simply ineffective. However, when larger beads with diameters of 3 and 5 mm were used, our porous microspheres were ground into submicron-sized particles. The quality of the resultant PLGA nanoparticles was demonstrated by size distribution measurement and field emission scanning electron microscopy. The present top-down process that contrasts with conventional bottom-up approaches might find application in manufacturing drug-loaded PLGA nanoparticles.

Chitosan-coated halloysite nanotube magnetic microspheres for carcinogenic colorectal hemorrhage and liver laceration in albino rats

“…Additionally, the light microscope was utilized to see how microspheres' size altered throughout wet milling. 23 The morphological study using optical microscopy was done to determine how the microspheres' size and shape related to one another. The microscopy photos display spherical particles with what appears to be internal granulation, and they also demonstrated homogeneity in terms of morphology among many microsphere components.…”

The Effect of Different Factors on Poly(lactic-co-glycolic acid) Nanoparticle Properties and Drug Release Behaviors When Co-Loaded with Hydrophilic and Hydrophobic Drugs

“…PLGA nanoparticles (PLGA NPs) as drug carriers offer notable benefits in the pharmaceutical industry [3,4]. Numerous techniques have been employed for the synthesis of PLGA NPs, wherein the emulsification method is the most widely used preparation method [5,6]. The particle size of PLGA NPs produced through emulsificationsolvent evaporation is influenced by various factors, such as the emulsifier type and the volume ratio between the organic and aqueous phases [7,8].…”

Fabrication of biodegradable hollow microsphere composites made of polybutylene adipate co-terephthalate/polyvinylpyrrolidone for drug delivery and sustained release

“…For example, Yuan [ 15 ] et al. prepared a curcumin-loaded microsphere using poly (lactic-co-glycolic acid) (PLGA) [ 16 , 17 ] as a shell material. The loading rate of curcumin by the microsphere is up to 48.78% ​± ​0.94, and the sustained release experiment in vitro showed that the microsphere is stably released within 40 days.…”