Elektrokemijska karakterizacija slojeva berlinskog modrila na ugljičnim elektrodama

undergraduate thesis

• Title (english): Electrochemical characterization of Prussian blue films on carbon electrodes
• Author: Andrej Molnar
• Mentor: Petar Kassal (mentor)
• Committee member: Petar Kassal (predsjednik povjerenstva)
• Committee member: Marijana Kraljić Roković (član povjerenstva)
• Committee member: Igor Dejanović (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2024-09-18, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

Biosenzori su korišteni dugi niz godina za određivanje koncentracije biomolekula. Najčešća izvedba biosenzora sadrži enzim oksidazu. Oksidaza oksidira supstrat, pri čemu nastaje oksidirani oblik supstrata i vodikov peroksid, kao sporedni produkt. Mjerenjem koncentracije vodikovog peroksida moguće je dobiti informacije o koncentraciji biomolekule. Pri tome koristimo berlinsko modrilo, koje je medijator koji selektivno katalizira redukciju vodikovog peroksida pri potencijalima bliskim 0,0 V prema Ag/AgCl elektrodi i pri tome ga detektira.
U ovom radu, berlinsko modrilo naneseno je kemijskom depozicijom, koja je spontana reakcija FeCl3 i K3[Fe(CN)6], na konvencionalnu elektrodu od staklastog ugljika, komercijalnu sitotiskanu elektrodu i inkjet ispisanu grafensku elektrodu tijekom različitih vremena depozicije. Deponirani sloj berlinskog modrila elektrokemijski je karakteriziran cikličkom voltametrijom u KCl te u fosfatnim puferima, te je ispitana pH-ovisnost odziva. Nakon provedenih cikličkih voltametrija, na ispisanim elektrodama je provedena kronoamperometrijska detekcija otopina vodikovog peroksida različitih koncentracija kako bi se provjerila funkcionalnost potencijalnih biosenzora. Cilj rada bio je odrediti optimalne uvjete depozicije berlinskog modrila za korištenje u biosenzorima.

Abstract (english)

Biosensors have been used for many years to determine the concentration of biomolecules. The most used configuration of biosensors is that involving the use of oxidase enzymes. Oxidase enzymes oxidize the substrate and produce an oxidized form of the substrate and hydrogen peroxide as a side product. The measurement of H2O2 concentration can provide information about the concentration of the target analyte. That is the reason why Prussian Blue is used, because it is a mediator that can selectively catalyze the reduction of hydrogen peroxide at an applied potential around 0,0 V vs Ag/AgCl and that way it can detect hydrogen peroxide. In this work, Prussian Blue was deposited chemically, by mixing FeCl3 and K3[Fe(CN)6] and drop casting the reaction mixture on a conventional glassy carbon electrode, commercial carbon-based screen-printed electrodes and in-house inkjet printed graphene electrodes with different times of deposition. Chemically deposited Prussian Blue layers were characterized electrochemically via cyclic voltammetry in KCl and phosphate buffers and the pH-response was evaluated. After recording cyclic voltamograms, chronoamperometric detection of hydrogen peroxide was conducted on printed electrodes to check the functionality of deposited layers. The goal of this work was to find optimal deposition conditions for biosensing applications.

• Keywords: berlinsko modrilo; inkjet ispis; elektrokemijski senzor
• Keywords (english): Prussian Blue; inkjet printing; electrochemical sensor
• Language: croatian
• URN:NBN: urn:nbn:hr:149:428705
• Project: Number: UIP-2020-02-9139; Title: Fotonsko sinteriranje inkjet ispisanih elektrokemijskih senzora i biosenzora na plastičnim podlogama; Title: Photonic sintering for inkjet printed electrochemical sensors and biosensors on plastic substrates; Acronym: PrintEChemSens; Leader: Petar Kassal; Jurisdiction: Croatia; Funder: Hrvatska zaklada za znanost; Funding stream: Installation Research Projects
• Study programme: Title: Applied Chemistry - Undergraduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry; Course: Advanced materials and technologies; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) primijenjene kemije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) primijenjene kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-11-16 21:11:32