Background:
Many drugs are delivered intranasally for local or systemic effect, typically in the form of
droplets or aerosols. Because of the high cost of in vivo studies, drug developers and researchers often turn to in vitro or in
silico testing when first evaluating the behavior and properties of intranasal drug delivery devices and formulations.
Recent advances in manufacturing and computer technologies have allowed for increasingly realistic and sophisticated in
vitro and in silico reconstructions of the human nasal airways.
Objective:
To perform a summary of advances in understanding of intranasal drug delivery based on recent in vitro and in
silico studies.
Conclusion:
The turbinates are a common target for local drug delivery applications, and while nasal sprays are able to
reach this region, there is currently no broad consensus across the in vitro and in silico literature concerning optimal
parameters for device design, formulation properties and patient technique which would maximize turbinate deposition.
Nebulizers are able to more easily target the turbinates, but come with the disadvantage of significant lung deposition.
Targeting of the olfactory region of the nasal cavity has been explored for potential treatment of central nervous system
conditions. Conventional intranasal devices, such as nasal sprays and nebulizers, deliver very little dose to the olfactory
region. Recent progress in our understanding of intranasal delivery will be useful in the development of the next
generation of intranasal drug delivery devices.
Preparation of hydroxyapatite/poly(lactic acid) hybrid microparticles for local drug delivery
