Targeted delivery of Tet1 peptide functionalized polymersomes to the rat cochlear nerve

Ya Zhang¹, Weikai Zhang^1*, Alexander H Johnston^2*, Tracey A Newman³, Ilmari Pyykkö¹, Jing Zou<sup>1

1</sup>Department of Otolaryngology, University of Tampere, Medical School, Tampere, Finland; ²Centre for Biological Sciences, ³Clinical Neurosciences, University of Southampton, Southampton, UK

*These authors are co-contributors

Abstract: Polymersomes are nanosized vesicles formed from amphiphilic block copolymers, and have been identified as potential drug delivery vehicles to the inner ear. The aim of this study was to provide targeting to specific cells within the inner ear by functionalizing the polymersome surface with Tet1 peptide sequence. Tet1 peptide specifically binds to the trisialoganglioside clostridial toxin receptor on neurons and was expected to target the polymersomes toward the cochlear nerve. The Tet1 functionalized PEG-b-PCL polymersomes were administered using routine drug delivery routes: transtympanic injection and cochleostomy. Delivery via cochleostomy of Tet1 functionalized polymersomes resulted in cochlear nerve targeting; in contrast this was not seen after transtympanic injection.

Keywords: nanoparticles, peptide, round window membrane, nerve fibers, spiral ganglion cell, drug delivery