Hearing impairment can be caused be different factors, such as: genetic defects, environmental factors or a combination of both. These factors induce the damage and death of hair cells and neurons in the cochlea, therefore cellular loss and concomitant hearing loss cannot be reversed.
Several administration routes for the inner ear drug delivery are possible: systemic, intra-cochlear, and intra-tympanic. This last approach posses several advantages over systemic drug delivery as it can bypass the blood labyrinth barrier and lead to higher drug concentration in the inner ear fluids. Unfortunately, large amounts of the administered drugs are usually eliminated by the Eustachian tube following IT drug delivery.
In order to increase the effectiveness of the treatment, several types of drug delivery systems were studied: biocompatible inorganic materials (silica), organic materials (liposomes, lipids, dendrimers), biodegradable natural-based polymers (gelatin, hyaluronic acid, alginate, chitosan, etc.) and synthetic polymers.
Targeted drug delivery was recently introduced for treating sensorineural hearing deficiency associated with hair cell pathology. In the last years, two possibilities of targeting these internal ear-specific cells were studied: directing the magnetizable drug carrier and concentrating it to the target site with the help of an external magnetic field or the functionalization of the drug carrier with specific ligands.
At the best of our knowledge, no studies exist concerning the investigation of a combined effect of these two types of NPs. Therefore, the main objective of this project is the preparation of drug-loaded peptide-functionalized magnetic nanocarriers capable of active targeting, under the action of a magnetic external field, and internalizing in the inner ear specific cells due to the peptide ligands. Two new types of nanocarriers will be studied within this project, such as: oligochitosan-based nanocapsules (NCs) and oligochitosan-coated liposomes (Ls).