The effect of solvent treatment on the performance of various carriers in dry powder inhalations containing salbutamol sulphate.

Abstract

Objective(s) : It has been suggested that the efficiency of dry poder inhaler (DPI) is generally low. Therefore, the aim of the present research work was to use the solvent treatment of the carrier in DPIformulations to see the possibility of inducing desirable characteristics. Lactose sieve fractions of 63-90 µm were submerged in ethanol or 80% v/v ethanol, methanol or propanol. Lactose crystals were then blended with either 1% w/w or 4% w/w salbutamol sulphate using a Turbula mixer. Drug detachment was studied using a multistage liquid. Laser particle size analyzer, DSC, and pycnometer were used to characterize the treated lactose and mannitol samples. SEM was used to study surface morphologies. In case of mannitol as a carrier only ethanol was used as a solvent. SEM images displayed less rugosities and increased surface smoothness after submersion. Although the tomahawk like shape remained fairly constant in most lactose samples, the solvent treatment changed the shape of mannitol particles which was proved by SEM results. Deposition results showed that the type of solvent had an influence on fine particle fraction. In addition, the payload had also a big impact on fine particle fraction values. Generally, treated samples showed better performance compared to untreated samples. Solid state analysis by DSC showed that no major changes occurred in the treated samples compared to untreated samples. The solvent treated method can be used as an approach to improve the performance of carriers such as lactose and mannitol in dry powder inhaler.