Preparation and in vitro aerosol performance of spray-dried Shuang-Huang-Lian corrugated particles in carrier-based dry powder inhalers.

The development of dry powder inhalation (DPI) products of traditional Chinese medicine (TCM) remains to be a challenge due to chemical complexity and batch-to-batch variations in constituent composition. This study was to investigate the feasibility of using spray-dried corrugated particles to improve the aerodynamic performance of a TCM, Shuang-Huang-Lian (SHL), in carrier-based DPI. Particles with different surface roughness were spray-dried by the addition of leucine and concomitant manipulation of spray-drying parameters. The surface roughness was determined by atomic force microscopy, whilst the aerodynamic performance of drug particle-mannitol/lactose blends was evaluated using a next-generation pharmaceutical impactor through a Cyclohaler. Although the emission efficiency for corrugated particle-based DPI was ~10% lower than that for smooth SHL, the fine particle fractions (FPF(<4.4 μm)) of 32.4-36.8% for the former were significantly higher than those of 14.7-16.2% for the latter. In particular, the FPF and fraction of drug detached from the carrier appeared not to be significantly affected by the variation in constituent composition of SHL. This study demonstrates that the use of corrugated particles in carrier-based DPI improved aerosol performance by facilitating drug detachment from the carrier, independent of variation in constituent composition, and such particles were potentially applicable to the development of SHL DPI products.