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A Comparative Study of Drug Delivery Methods Targeted to the Mouse Inner Ear: Bullostomy Versus Transtympanic Injection
Published on: March 8, 2017
A novel chitosan-hydrogel-based nanoparticle delivery system for local inner ear application.
Shayanne A Lajud1, Danish A Nagda, Peter Qiao
1*Department of Otorhinolaryngology-Head and Neck Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; †Department of Neuroscience, Baylor College of Medicine, Houston, Texas; and ‡Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, U.S.A.
A novel chitosan-hydrogel nanoparticle system effectively delivers therapeutic biomaterials across the round window membrane into the inner ear. This nanohydrogel shows potential for controlled drug delivery to treat inner ear conditions.
Area of Science:
- Biomedical nanotechnology
- Drug delivery systems
- Inner ear therapeutics
Background:
- Inner ear drug delivery presents significant challenges for otolaryngologists.
- Advances in nanotechnology and understanding of the round window membrane (RWM) properties are driving interest in nanoparticle-based delivery.
- Novel therapeutic targets and agents necessitate improved localized delivery methods.
Purpose of the Study:
- To develop and evaluate a chitosan-hydrogel-based nanoparticle (nanohydrogel) system for delivering therapeutic biomaterials across the RWM into the inner ear.
- To assess the in vitro properties and in vivo efficacy of the nanohydrogel for controlled inner ear drug delivery in a mouse model.
Main Methods:
- Fluorescently labeled liposomal nanoparticles (NPs) were encapsulated within a chitosan hydrogel to create the nanohydrogel.
- In vitro studies evaluated NP properties, stability, and release kinetics.
- In vivo studies in mice assessed NP delivery, distribution within the inner ear, and morphological changes via perilymph and tissue analysis.
Main Results:
- The nanohydrogel successfully delivered intact nanoparticles (average diameter 160 nm) into the inner ear's perilymphatic system.
- In vitro, liposomal NPs remained stable for over two weeks, and the nanohydrogel demonstrated controlled, sustained NP release.
- In vivo, nanoparticles reached cellular structures in the scala media without apparent damage to inner ear structures.
Conclusions:
- The developed nanohydrogel system is a promising platform for controlled and sustained therapeutic delivery from the middle ear to the inner ear.
- This approach offers a potential solution for treating inner ear disorders without causing structural damage.
