Geometrijska optimizacija elektroda za kapacitivnu neurostimulaciju

master's thesis

• Title (english): Geometric optimization of electrodes for capacitive neurostimulation
• Author: Anja Mioković
• Mentor: Vedran Đerek (mentor)
• Committee member: Vedran Đerek (predsjednik povjerenstva)
• Committee member: Hrvoje Buljan (član povjerenstva)
• Committee member: Mario Novak (član povjerenstva)
• Committee member: Željko Skoko (član povjerenstva)
• Committee member: Davor Horvatić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Physics); Zagreb
• Defense date and country: 2022-02-25, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract

Električna neurostimulacija ciljano je pobuđivanje neurona ili dijelova središnjeg živčanog sustava električnom strujom. Organski elektrolitski fotokondenzatori (OEPC, eng. organic electrolytic photocapacitor) su nedavno razvijeni opto-bioelektronički elementi, bazirani na p-n dvosloju organskih poluvodiča, sa svrhom kapacitivne neurostimulacije. Njome se osigurava odsutnost elektrokemijskih faradayskih reakcija na elektrodama i izbjegava stvaranje slobodnih radikala i metalnih iona u blizini bioelektroničkog implantata. Za sigurnu i učinkovitu kapacitivnu neurostimulaciju poželjno je prostorno ograničiti njezino djelovanje na ciljano područje, te ograničiti neželjeni protok struje kroz osjetljiva područja tkiva. Prilikom odabira geometrije fotokondenzatora potrebno je razumjeti 3D prostiranje električnog polja oko njega. U okviru ovoga diplomskoga rada, osmisljen je i osposobljen eksperimentalni postav za izravno mjerenje prostiranja tranzijentnog električnog potencijala u 3D prostoru elektrolita oko fotokondezatora proizvoljne geometrije. Izmjerene su jednostavne kružne geometrije fotokondezatora te su rezultati mjerenja uspoređeni s rezultatima numeričkog modela fotokondezatora izrađenog softverskim paketom ”COMSOL Multiphysics”. Cilj diplomskog rada jest provjera i potvrda valjanosti korištenog modela, kako bi se on u budućnosti mogao koristiti za optimizaciju geometrije pobudne i povratne elektrode za različite željene scenarije primjene implantata.

Abstract (english)

Electrical neurostimulation is the targeted excitation of neurons or parts of the central nervous system by an electric current. Organic electrolytic photocapacitors (OEPC) are recently developed opto-bioelectronic devices, based on the p-n bilayer of organic semiconductors, with the purpose of capacitive neurostimulation. It ensures the absence of electrochemical Faradaic reactions on the electrodes and avoids the generation of free radicals and metal ions in the vicinity of the bioelectronic implant. For safe and effective capacitive neurostimulation, it is desirable to spatially limit its effect to the target area, and to limit the unwanted current flow through sensitive areas of tissue. When choosing the geometry of a photocapacitor, it is necessary to understand the 3D propagation of the electric field around it. As part of this thesis, an experimental setup for direct measurement of the propagation of transient electric potential in the 3D space of the electrolyte around a photocapacitor of arbitrary geometry was assembled. Simple circular geometries of the photocapacitor were measured and the measurement results were compared with the results of the numerical model of the photocapacitor developed within the ”COMSOL Multiphysics” software package. The aim of the thesis is to check and validate the used model, so that it can be used in the future to optimize the geometry of the excitation and return electrodes for different desired implant application scenarios.

• Keywords: optoelektrična neurostimulacija; p-n dvosloj organskih poluvodiča; fotokapacitivna neurostimulacija; tranzijentni električni potencijal
• Keywords (english): optoelectronic neurostimulation; p-n bilayer of organic semiconductors; photocapacitive neurostimulation; transient electric potential
• Language: croatian
• URN:NBN: urn:nbn:hr:217:205554
• Study programme: Title: Physics; specializations in: Research; Course: Research; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: magistar/magistra fizike (magistar/magistra fizike)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2022-03-21 09:58:02