Session Speaker
Nano dry Powder Inhalations:
A New Approach for Treating Broncho-Constrictive Conditions
Farhan Jalees Ahmad
Nanoparticle DPI is known to have deeper lung
penetration but its clinical utility as a potentially better treatment
option needs to be evaluated in the light of higher expected mucociliary
movement of the nanoparticles compared to micronized DPI. The objective
of this study was to make nano-salbutamol sulphate (SBS) DPI, radiolabel
it with Tc-99m using a novel surface labeling methodology, characterize
the formulation and assess its in vitro and in vivo deposition in
healthy human volunteers to estimate its bio-availability in the target
area. Nano-SBS with a mean particle of 60.71 ±
35.99 nm was produced using liquid anti-solvent precipitation method.
The drug particles were spherical, pure and crystalline. Ander-son
cascade impaction showed that blend formulations of Nano-SBS exhibited
signi?cantly higher respi-rable fraction 45.2% compared to the known
behavior of micronized salbutamol sulphate blends. Though the particle
size tended to increase due to solid phase interaction after blending
with lactose, there was de?nitive correlation between the radiolabeled
and non-radiolabeled forms. In 10 healthy volunteers, lower oropharyngeal
depositions (25.3 ±
4.5%) were observed with nano-SBS formulation compared to micronized
SBS formulation (58.4 ±
6.1%). Furthermore, Nano-SBS formulations showed nearly 2.3-fold increases
in total lung deposition compared to micronized SBS. The in vivo deposition
data and the ratio of peripheral to central lung deposition (P/C)
of 1.12 ±
0.4 indicate that Nano-SBS is evenly distributed within different
lung regions. As demonstrated for SBS, nano-sizing may enhance regional
deposition and thus provide an attractive particle engineering option
for the development of blend formulations for inhalation delivery.
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