Effect of magnesium stearate surface coating method on the aerosol performance and permeability of micronized fluticasone propionate

Improving Inhalation Performance with Particle Agglomeration via Combining Mechanical Dry Coating and Ultrasonic Vibration

“…Mechanical dry-coating of MgSt on DPI enhances fine particle deposition but influences the dissolution rate, as previously reported [ 47 ]. The dissolution of aerosolized drug particles on the surface of the lung epithelium is the first step in achieving good bioavailability.…”

“…Because of the significant effect of the incorporation of MgSt on lowering the cohesive force of fine particles and enhancing the aerosol performance of DPI [ 47 ], the effect of mechanical dry-coating on its own and in combination with ultrasonic vibration (200 W power input) on the spherical agglomerate bulk properties and aerodynamic deposition was further investigated. As shown in Table 6 , the combination of ultrasonic vibration and mechanical dry-coating contributed to an overall improved drug content but decreased mean and rupture force compared to those achieved with mechanical dry-coating on its own.…”

“…This comprehensive factor indicated the sufficient dispersion of API, which enhanced the solubility and hydrophobicity of MgSt to hinder dissolving. This was only true with lower MgSt concentrations, because the ultra-thin layer of the MgSt coating on the lactose surface may not have been sufficient to hinder water penetration and decrease the dissolution rate, but once the hydrophobic component was increased to a certain limit, slower dissolution rate was observed [ 47 ]. For the 3% MgSt formulation, it appeared that drug particles were encased in lactose aggregates and hindered the wettability, resulting in slower dissolution, but ultrasonic vibration dispersed the API and MgSt uniformly, which in turn enabled full dissolution.…”