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Determination of vitamin B1, B2 and B3 by means of chronopotentiometry and chronopotentiometric stripping analysis

dc.contributor.advisorSuturović, Zvonimir
dc.contributor.otherStojanović, Zorica
dc.contributor.otherSuturović, Zvonimir
dc.contributor.otherKos, Jovana
dc.creatorBrezo-Borjan, Tanja
dc.date.accessioned2019-10-17T11:21:33Z
dc.date.available2019-10-17T11:21:33Z
dc.date.available2020-07-03T13:55:12Z
dc.date.issued2019-10-14
dc.identifier.urihttps://nardus.mpn.gov.rs/handle/123456789/11437
dc.identifier.urihttps://www.cris.uns.ac.rs/DownloadFileServlet/Disertacija156413415887336.pdf?controlNumber=(BISIS)111000&fileName=156413415887336.pdf&id=13260&source=NaRDuS&language=srsr
dc.identifier.urihttps://www.cris.uns.ac.rs/record.jsf?recordId=111000&source=NaRDuS&language=srsr
dc.identifier.urihttps://www.cris.uns.ac.rs/DownloadFileServlet/IzvestajKomisije156413416875343.pdf?controlNumber=(BISIS)111000&fileName=156413416875343.pdf&id=13261&source=NaRDuS&language=srsr
dc.description.abstractU okviru ove doktorske disertacije razvijene su elektroanalitičke metode za određivanje pojedinih vitamina B grupe. Za određivanje vitamina B1 i B3 primenjena je adsorpciona hronopotenciometrijska striping analiza (AdHSA) na tankoslojnoj živinoj elektrodi kao radnoj elektrodi, dok je za određivanje vitamina B2 primenjena hronopotenciometrijska analiza (HA) na dvema geometrijski različitim elektrodama od staklastog ugljenika: planarnoj disk elektrodi i elektrodi u vidu procesne posude. U cilju optimizacije metoda ispitan je uticaj najznačajnijih eksperimentalnih faktora. Optimalni eksperimentalni uslovi za određivanje vitamina B1 su podrazumevali primenu 0,2 mol/l citratnog pufera vrednosti pH 6 kao pomoćnog elektrolita, potencijala i vremena akumulacije od -1,313 V i 50 s, redom, i struje rastvaranja depozita od 1,9 – 6,1 μA. Odgovarajući eksperimentalni faktori za određivanje vitamina B2 su bili: 0,025 mol/l HCl kao pomoćni elektrolit, inicijalni potencijal od 0,023 V i struja redukcije od 0,8 – 4,2 μA, dok su optimalni radni uslovi za određivanje vitamina B3 obuhvatali primenu 0,05 mol/l citratnog pufera pH 6, potencijala akumulacije od -1,405 V pri vremenu akumulacije od 15 s, i struji rastvaranja u intervalu od 1,4 – 15,1 μA. U slučaju određivanja vitamina B2 primenom radne elektrode u vidu procesne posude ispitan je i uticaj aktivne površine radne elektrode na analitički signal vitamina B2. Optimalna vrednost aktivne površine radne elektrode iznosila je 13,4 cm2. Pod optimalnim eksperimentalnim uslovima, dolazilo je do elektrooksidacije molekula vitamina B1 i B3 na tankoslojnoj živinoj elektrodi u analitičkom koraku, dok se vitamin B2 redukovao na elektrodama od staklastog ugljenika. U okviru validacije metoda definisani su opsezi linearnosti, određene su vrednosti granice detekcije i granice kvantitativnog određivanja, ocenjena je preciznost i ispitane su interferencije. Uz odgovarajuće uslove rada, dobijena je dobra linearnost analitičkog signala od sadržaja za sva tri ispitivana vitamina. Ostvarene su granice detekcije od 1,64 mg/l za vitamin B1, 0,076 mg/l za vitamin B2 uz primenu planarne disk elektrode i 0,018 mg/l (vitamin B2) uz primenu procesne posude od staklastog ugljenika kao radne elektrode. Ostvarena granica detekcije za vitamin B3 je iznosila 2,20 mg/l. Nakon optimizacije i validacije, razvijene metode HA i AdHSA primenjene su za određivanje vitamina B1, B2 i B3 u komercijalnim multivitaminskim dodacima ishrani i multivitaminskim instant napicima. Tačnost razvijenih metoda je potvrđena paralelnim analizama izvedenim primenom visokopritisne tečne hromatografije.sr
dc.description.abstractWithin the scope of this doctoral dissertation, electroanalytical methods for the determination of several vitamins of the B-complex are developed. For the determination of vitamin B1 and B3 adsorptive chronopotentiometric stripping analysis was applied, with mercury film electrode as the working electrode. For vitamin B2 determination, the chronopotentiometric analysis was performed on two geometrically different glassy carbon working electrodes: the planar disc electrode and the process vessel electrode. The most important experimental parameters of the analysis were investigated and optimized. For vitamin B1 determination, the optimized experimental conditions were: 0,2 mol/l citrate buffer pH 6 as the supporting electrolyte, accumulation potential of -1,313 V, accumulation time of 15 s and the oxidation current between 1,9 μA and 6,1 μA. The appropriate experimental factors for vitamin B2 determination included 0,025 mol/l HCl solution (supporting electrolyte), initial potential of 0,023 V and reduction current in the range from 0,8 – 4,2 μA, whereas the optimal working parameters for vitamin B3 determination were as follows:0,05 mol/l citrate buffer pH 6, accumulation potential of -1,405 V, accumulation time of 15 s and dissolution current from 1.4 – 15.1 μA. When the process vessel was used as the working electrode, the optimal volume of the analyzed solution i.e. the active surface area of the electrode was optimized. The optimal value of the active surface area was 13,4 cm2. As well, under the optimal experimental conditions, vitamin B1 and vitamin B3 underwent electrooxidation process in the analytical step, whereas vitamin B2 was electrochemically reduced on glassy carbon electrodes. A validation procedure of the optimized methods was performed by evaluation of the following parameters: linearity, the limit of detection (LOD), the limit of quantitation (LOQ), precision, selectivity, and accuracy. Under optimal working conditions, the linearity of the proposed methods was very good. The achieved limits of detection were 1.64 mg/l for vitamin B1, 0,076 mg/l for vitamin B2 (planar disc electrode) and 0,018 mg/l (process vessel electrode) and 2,2 mg/l for vitamin B3. After optimization and validation procedures, the developed methods were applied for vitamin B1, B2, and vitamin B3 determination in commercially available multivitamin supplements and instant multivitamin beverages. The accuracy of the proposed methods was tested by parallel HPLC analyses of the same samples.en
dc.languagesr (latin script)
dc.publisherУниверзитет у Новом Саду, Технолошки факултетsr
dc.relationinfo:eu-repo/grantAgreement/MESTD/Integrated and Interdisciplinary Research (IIR or III)/46009/RS//
dc.rightsopenAccessen
dc.rights.urihttps://creativecommons.org/licenses/by/4.0/
dc.sourceУниверзитет у Новом Садуsr
dc.subjectvitamin B1sr
dc.subjectvitamin B1en
dc.subjectvitamin B2en
dc.subjectvitamin B3en
dc.subjectchronopotentiometryen
dc.subjectchronopotentiometric stripping analysisen
dc.subjectmultivitamin supplementsen
dc.subjectvitamin B2sr
dc.subjectvitamin B3sr
dc.subjecthronopotenciometrijasr
dc.subjecthronopotenciometrijska striping analizasr
dc.subjectmultivitaminski dodaci ishranisr
dc.titleOdređivanje vitamina B1, B2 i B3 primenom hronopotenciometrije i hronopotenciometrijske striping analizesr
dc.title.alternativeDetermination of vitamin B1, B2 and B3 by means of chronopotentiometry and chronopotentiometric stripping analysisen
dc.typedoctoralThesisen
dc.rights.licenseBY
dc.identifier.fulltexthttp://nardus.mpn.gov.rs/bitstream/id/40541/Disertacija.pdf
dc.identifier.fulltexthttp://nardus.mpn.gov.rs/bitstream/id/40542/IzvestajKomisije.pdf
dc.identifier.fulltexthttps://nardus.mpn.gov.rs/bitstream/id/40541/Disertacija.pdf
dc.identifier.fulltexthttps://nardus.mpn.gov.rs/bitstream/id/40542/IzvestajKomisije.pdf
dc.identifier.rcubhttps://hdl.handle.net/21.15107/rcub_nardus_11437


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