A comparison of spherical and cylindrical microparticles composed of nanoparticles for pulmonary application

Abstract

Nano-embedded microparticles represent promising carrier systems to tackle the challenges of nanoparticle delivery into the lungs by inhalation. While spray drying is widely used for the incorporation of nanoparticles into microparticles, the template-assisted technique is a novel method to prepare aspherical, cylindrical microparticles composed of nanoparticles. In this work, both techniques were applied to produce both spherical and cylindrical nanoembedded microparticles. For both geometries particles consisting of gelatin nanoparticles, mannitol and leucine were prepared in three different sizes each. Cylindrical microparticles could be prepared with defined dimensions and narrow size distributions, allowing to target a wide range of aerodynamic diameters. The size of spherical microparticles was influenced by the spraying feed concentration, yielding only small differences in geometric and aerodynamic diameters and broad particle size distributions. Regarding the redispersibility of the nano-embedded microparticles, spherical particles showed better disintegration behavior and higher nanoparticle release in comparison to cylindrical particles upon contact with water. The template-assisted technique yielded higher nanoparticle content in contrast to spray drying. In summary, cylindrical particles represent a promising drug delivery system with high potential for later application. However, further improvements in the preparation method are required to enable higher yields and a possible later scale-up.

Cylindrical Microparticles Composed of Mesoporous Silica Nanoparticles for the Targeted Delivery of a Small Molecule and a Macromolecular Drug to the Lungs: Exemplified with Curcumin and siRNA

“…The particle concentrations in each stage were then analysed using a microplate spectrophotometer (TecanReader ® infinite M200, Tecan, Männedorf; Switzerland) to determine the Mass Median Aerodynamic Diameter (MMAD), Fine Particle Fraction (FPF) and Geometric Standard Deviation (GSD). The calculation of these values was performed analogous to Abdelrahim et al [51] as already described in different publications [52,53].…”

Paclitaxel loaded poly (DL lactic acid co castor oil) 60:40 with poloxamer‐F68 rod shape cylindrical nanoparticle preparation and in vitro cytotoxicity studies

“…There is, however, a growing involvement in utilizing nonspherical particle shapes including flat disks, cylinders, elongated liposomes, filomicelles, and carbon tubes. It is potential to manipulate the size and shape of polymeric nanoparticles by controlling the hydrophilic and hydrophobic properties of polymers, solvent processes, and polymerization of the nanoparticles . Our study synthesized and used cylindrical nanoparticles within PTX.…”

“…It is potential to manipulate the size and shape of polymeric nanoparticles by controlling the hydrophilic and hydrophobic properties of polymers, solvent processes, and polymerization of the nanoparticles. [16][17][18][19][20] Our study synthesized and used cylindrical nanoparticles within PTX. The poly (DL lactic acid co castor oil) 4:6.…”

Numerical simulation of ellipsoidal particles deposition in the human nasal cavity under cyclic inspiratory flow

“…There is a wide variety of hazardous particles in different sizes and shapes (e.g., needle-like, cylindrical and ellipsoidal particles) in the air, specifically in the industrial regions. As these particles are inhaled, they may penetrate into the lower parts of the human respiratory system and cause serious health effects including asthma, cardiovascular diseases and lung cancer [1,2]. Hence, this concern has gained considerable attention from researchers to study the behavior of non-spherical particles in the human nasal cavity, as it is the first passage to filter and control the breathing air.…”