The physicochemical properties of two forms of spray dried bovine serum albumin (BSA) have been investigated using particle sizing, surface energy measurement, atomic force microscopy (AFM) and colloid probe microscopy. The BSA powder had similar particle size distributions and surface energy but si
The influence of mechanical processing of dry powder inhaler carriers on drug aerosolization performance
β Scribed by Paul M. Young; Hak-kim Chan; Herbert Chiou; Stephen Edge; Terence H.S. Tee; Daniela Traini
- Publisher
- John Wiley and Sons
- Year
- 2007
- Tongue
- English
- Weight
- 358 KB
- Volume
- 96
- Category
- Article
- ISSN
- 0022-3549
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β¦ Synopsis
The influence of processing on the performance of carrier material used in dry powder inhalers was investigated. a-Lactose monohydrate crystals were processed by ball milling for cumulative time durations and their properties evaluated. As expected, milling reduced the median particle diameter while increasing fine particulate (<10 mm) and amorphous levels. Recrystallization of these partially amorphous samples resulted in a reduction in fines, elimination of amorphous material with little change in median diameter. To study the effects of processing on aerosolization performance, blends of lactose monohydrate with a model drug (nedocromil sodium trihydrate), were evaluated using an in vitro multistage liquid impinger (MSLI) model. In general, milling and storage of the carriers at high humidity (prior to blending) had a significant (ANOVA, p < 0.05) effect on the fine particle fractions (FPF; <6.8 mm). These effects were attributed predominantly to the fines content, showing a strong correlation between increased fines and FPF (R 2 ΒΌ 0.974 and 0.982 for milled and recrystallized samples, respectively). However, this relationship only existed up to 15% fines concentration, after which agglomerate-carrier segregation was observed and FPF decreased significantly. These results suggest that, after processing, high-dose drug formulation performance is dominated by the presence of fines.
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