Comparison of the distribution pattern of PEG-b-PCL polymersomes delivered into the rat inner ear via different methods

Abstract

Cochleostomy resulted in distribution of the PMs in the spiral ligament (SL), mesothelial cells beneath the organ of Corti, supporting cells in the organ of Corti, and spiral ganglion cells (SGCs). Transtympanic injection induced uptake of the PMs in the SL and mesothelial cells beneath the organ of Corti. Topical administration showed distribution of the PMs only in the SL. In the vestibulum, transtympanic injection and cochleostomy induced more distribution of the PMs than did topical RWM delivery (p < 0.05, Kruskal-Wallis test).

Inner ear delivery: Challenges and opportunities

“…Likewise, nanohydrogel consisting of liposomal nanoparticles loaded onto a chitosan‐based hydrogel acts as a reservoir to release nanoparticles in a controlled and sustained manner into the perilymphatic system . Nanoparticles have also been introduced directly into the inner ear via cochleostomy, with improved distribution over intratympanic injection alone …”

“…Direct delivery of therapeutics into the cochlea offers several advantages over intratympanic injection, including bypassing the variability imposed by the properties of the RWM, attaining higher peak concentrations of drug, and reducing basal‐apical gradients of a drug within the scala tympani compared to intratympanic application of a drug . Early models for intracochlear injection utilized cochleostomy for direct microinjection of drugs or infusion of drugs into the cochlea using osmotic minipumps (Figure ) . Newer ideas include introducing a PLGA‐based implant into the scala tympani via a cochleostomy in the basal turn of the cochlea.…”

“…7,78,79 Early models for intracochlear injection utilized cochleostomy for direct microinjection of drugs or infusion of drugs into the cochlea using osmotic minipumps ( Figure 4). 74,[80][81][82][83][84][85] Newer ideas include introducing a PLGA-based implant into the scala tympani via a cochleostomy in the basal turn of the cochlea.…”

The effect of dexamethasone/cell-penetrating peptide nanoparticles on gene delivery for inner ear therapy

“…HEI-OC1 cells were plated in 96-well plates at a density of 1×10 4 /well in 0.1 mL complete growth medium and incubated to 80% confluence for 24 h. The cells were then treated with Penetratin, Tat, and Arg8 peptides conjugated with rhodamine and DMSO as a vehicle for 24 h. Cell viability was determined using a commercially available 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay according to the manufacturer's protocol (EZ-Cytox; Daeil Lab, Seoul, South Korea). After incubation, the optical densities of the samples were determined at 450 nm using a microplate reader (Bio-Rad Laboratories, Hercules, CA, USA Briefly, PSI was dissolved in DMF at a concentration of 138.6 mg/mL, and C18 was dissolved in DMF at 70°C.…”

“…3 Nanoparticles offer targeted drug delivery to specific cells. 3 Many kinds of nanoparticles including polymersomes, 4 solid lipid nanoparticles, 5 and polylysine 6 have been used as inner ear delivery carriers, and the functionalization of peptide moieties on their surfaces has also been reported to target the special cell populations of the inner ear, such as spiral ganglion neuron and…”