Elektrokemijsko određivanje polifenola

master's thesis

• Title (english): Electrochemical determination of polyphenols
• Author: Mario Roboz
• Mentor: Božidar Grabarić (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Chemistry and Biochemistry); (Laboratory for General and Inorganic Chemistry and Electroanalysis); Zagreb
• Defense date and country: 2004-12-20, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Elektrokemijsko određivanje polifenola u popularnim pićima (čajevi, crno vino i kava) temelji se na elektrokemijskoj oksidaciji polifenola na grafitnoj elektrodi. S obzirom da je jakost struje pri oksidacijskom potencijalu polifenola proporcionalna njihovoj koncentraciji, to svojstvo je korišteno za određivanje koncentracije polifenola u uzorcima. Odnos koncentracije referentnih polifenola (galna kiselina, pirogalol i pirokatehol) i jakosti struje pri oksidacijskom potencijalu nije linearan u korištenom području koncentracija polifenola (od 0,05 do 0,8 µM), već je aproksimiran polinomima trećeg i četvrtog stupnja za potrebe izrade baždarnih dijagrama. Određivanje polifenola diferencijalnom pulsnom voltametrijom uspoređeno je sa standardnom metodom mjerenja ukupnih polifenola pomoću Folin-Ciocalteauove reakcije.

Abstract (english)

Electrochemical determination of polyphenols in popular beverages (teas, red wine and coffee) is based on electrochemical oxidation of polyphenols at graphite electrode. Since the current at oxidation potential of polyphenols is proportional to their concentration, that property was used for determination of polyphenol concentration in the samples. Relation between concentration of referent polyphenols (gallic acid, pyrogaloll and pyrocatechol) and current at the oxidation potential in used concentration area of polyphenols (from 0.05 to 0.8 µM) isn't linear, so it was aproximated by polynomials of the third and fourth degree for working out calibration diagrams. Determination of polyphenols by means of differential pulse voltammetry was compared to a standard method od mesuring total polyphenols by means of Folin-Ciocalteau reaction.

• Keywords: polifenoli; diferencijalna pulsna voltametrija; čaj; vino; kava
• Keywords (english): polyphenols; differential pulse voltammetry; tea; wine; coffee
• Language: croatian
• URN:NBN: urn:nbn:hr:159:859958
• Study programme: Title: Biotechnology; specializations in: Biochemical Engineering; Course: Biochemical Engineering; Study programme type: university; Study level: graduate; Academic / professional title: diplomirani inženjer biotehnologije; smjer biokemijsko inženjerstvo (diplomirani inženjer biotehnologije; smjer biokemijsko inženjerstvo)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-09-13 07:24:30