Određivanje analitičkih značajki čvrstofazne amonij-selektivne elektrode

master's thesis

• Title (english): Determination of analytical parameters of a solid state ammonium-selective electrode
• Author: Željka Boček
• Mentor: Petar Kassal (mentor)
• Committee member: Petar Kassal (predsjednik povjerenstva)
• Committee member: Matija Cvetnić (član povjerenstva)
• Committee member: Zoran Mandić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2023-07-12, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

U ovom radu primjenom elektroanalitičkih tehnika određene su analitičke značajne čvrstofazne amonij-selektivne elektrode – osjetljivost, granica detekcije, linearno područje, vrijeme odziva, stabilnost i selektivnost. Uz navedene analitičke značajke ispitana je i reverzibilnost u linearnom području. Na poliimidnu podlogu inkjet ispisom naneseni su srebrni elektrodni supstrat i grafenski čvrsti kontakt. Nakon termičkog i fotonskog sinteriranja na pripremljenu elektrodu nakapana je polimerna amonij-selektivna membrana s nonaktinom kao ionoforom. Potenciometrijskim mjerenjima dobivene su baždarne i dinamičke krivulje u standardnim otopinama kloridnih soli primarnog iona (NH4+), iona interferenata (K+, Na+, Ca2+, Mg2+) i primarnog iona s konstantnom koncentracijom interferentnog iona. Osjetljivost, granica detekcije i linearno područje određeni su iz ovisnosti izmjerene elektromotorne sile o logaritmu aktiviteta NH4+ iona, dok je vrijeme odziva izračunato iz istovremeno određene dinamičke krivulje. Stabilnost naponskog odziva elektrode ispitana je testom na vodeni sloj. Potenciometrijski koeficijenti selektivnosti određeni su metodom odvojenih otopina i metodom miješanih otopina.

Abstract (english)

Analytical parameters of an all-solid-state ammonium selective electrode – sensitivity, limit of detection, linear range, response time, stability and selectivity were determined by using electroanalytical methods. Reversibility in the linear range was also tested. Silver electrode substrate and graphene solid contact were inkjet printed on polyimide substrates. After thermal and photonic sintering, polymeric ammonium-selective membrane with nonactin as the ionophore was drop-cast on top of the prepared electrode. Calibration and dynamic potential curves were obtained via potentiometric measurements in the chloride solutions of the primary ion (NH4+), interferent ions (K+, Na+, Ca2+, Mg2+) and the primary ion with a constant background of interferent ion. Sensitivity, limit of detection and linear range were determined from the calibration curve recorded in primary ion solutions of varying activities, while the response time was determined from the dynamic potential response curve obtained simultaneously. Potential stability of the ammonium-selective electrode was explored through water layer test. Potentiometric selectivity coefficients were determined via separate solution method and fixed interference method.

• Keywords: čvrstofazna ion selektivna elektroda; inkjet ispis; selektivnost; vodeni sloj
• Keywords (english): all-solid-state ammonium-selective electrode; inkjet printing; selectivity; water layer
• Language: croatian
• URN:NBN: urn:nbn:hr:149:519567
• 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: HRZZ; Funding stream: UIP
• Study programme: Title: Applied Chemistry - Graduate 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: graduate; Academic / professional title: magistar/magistra primijenjene kemije (magistar/magistra primijenjene kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2023-07-27 09:45:25