10.1371/journal.pone.0147552.g003 Maciej Wilk Maciej Wilk Roland Hessler Roland Hessler Kenneth Mugridge Kenneth Mugridge Claude Jolly Claude Jolly Michael Fehr Michael Fehr Thomas Lenarz Thomas Lenarz Verena Scheper Verena Scheper Dexamethasone release rates from guinea pig electrode measured in vitro. Public Library of Science 2016 round window membrane approach implantation impedance levels round window niche DEX Dexamethasone Eluting Electrode BackgroundThe efficiency attenuating electrode impedance CI electrode arrays electrode array tissue growth guinea pig cochleae auditory brainstem responses Fibrous Tissue Growth 2016-02-03 21:50:15 Figure https://plos.figshare.com/articles/figure/Dexamethasone_release_rates_from_guinea_pig_electrode_measured_in_vitro_/2603887 <p>The first 4 mm of the electrode array were immersed into 1 ml of saline solution at 37°C. The saline solution was periodically sampled and DEX concentrations were measured by HPLC-MS (Agilent 1200 HPLC coupled with a Bruker MicrOTOF-Q II MS-detector). Representative release profile measurements for the 1% (red squares) and 10% (blue triangles) DEX loaded electrodes are shown. Over the experimental time period (91 days) the average release rate of DEX from the 1% and 10% loaded electrodes was estimated to be in the order of 16 ng/day and 49 ng/day respectively. DEX release rates were higher in the initial elution period (e.g. average over the first five days: 62 ng/day and 166 ng/day respectively for the 1% and 10% electrodes) with a slow decay over time.</p>