20.500.12556/DKUM-90535 Določanje sledov benzo(a)pirena v vodi s plinsko kromatografijo z masno spektrometrijo magistrsko delo Trace level determination of benzo(a)pyrene in water by gas chromatography with mass spectrometry Policiklični aromatski ogljikovodiki (PAO) so močno lipofilne organske komponente, ki so vseprisotne v okolju in v zadnjih letih vzbujajo veliko pozornost zaradi svoje rakotvornosti. Nastajajo med nepopolnim izgorevanjem organskih snovi, tudi med pripravo živil in pri kajenju. Vedno jih najdemo kot mešanico posameznih komponent. V vodi so, zaradi nizke vodotopnosti in velike afinitete do trdnih delcev, njihove koncentracije zelo nizke. Prisotnost PAO v vodah tako kaže na onesnaženje. Namen magistrske naloge je bil kvantitativno določiti benzo(a)piren v vzorcih površinskih vod na zelo nizkih koncentracijskih nivojih. Uredba o stanju površinskih voda določa okoljski standard kakovosti za benzo(a)piren, ki znaša 0,05 ng/L, kar zahteva uporabo občutljivih instrumentalnih analiznih tehnik. Vsebnost benzo(a)pirena v vodi smo določili z uporabo optimizirane analizne metode, ki temelji na že uporabljeni in validirani metodi. Uporabili smo ekstrakcijo tekoče-tekoče z diklorometanom v lijih ločnikih. Po ekstrakciji smo ločeni organski fazi dodali brezvodni natrijev sulfat in ustrezne raztopine standardov ter jo skoncentrirali na željeni volumen. V tako pripravljenih vzorcih smo benzo(a)piren določili s tehniko plinske kromatografije z masno selektivnim detektorjem (GC/MSD). Kromatograme smo posneli z metodo izbranih ionov (SIM – selected ion monitoring). Za kvantitativno določitev smo uporabili mešano raztopino šestnajstnih internih standardov. Rezultati so pokazali, da je optimizirana analizna metoda primerna za zanesljivo določanje sledov benzo(a)pirena v vodi, saj so bili izkoristki pri določanju ponovljivi in znotraj predpisanega kriterija. Ugotovili smo prisotnost vpliva matrice oz. osnove vzorca, saj so bili izkoristki v topilu previsoki. Zato smo pripravili umeritveno krivuljo v matrici vode, kjer smo zadostili kriterijem (izkoristki so bili od 70 % do 110 %). Polycyclic aromatic hydrocarbons (PAHs) are highly lipophilic organic compounds that are ubiquitous in the environment and have attracted much attention in recent years due to their carcinogenicity. They are formed during the incomplete combustion of organic substances, including during food preparation and smoking. They always occur as a mixture of individual compounds. Their concentrations in water are very low due to their low solubility in water and their high affinity for solid particles. The presence of PAHs in water therefore indicates pollution. The aim of the master's thesis was the quantitative determination of benzo(a)pyrene in surface water samples at very low concentration levels. Ordinance on the Status of Surface Waters sets an environmental quality standard for benzo(a)pyrene of 0,05 ng/L, which requires the use of sensitive instrumental analysis techniques. The level of benzo(a)pyrene in water was determined using an optimized analytical method based on a previously used and validated method. We used a liquid-liquid extraction with dichloromethane in separatory funnels. After extraction, anhydrous sodium sulfate and appropriate standard solutions were added to the separated organic phase and concentrated to the desired volume. Benzo(a)pyrene was determined in the samples prepared in this way using the gas chromatography technique with mass selective detector (GC/MSD). The chromatograms were recorded using the selected ion monitoring (SIM) method. A mixed solution of sixteen internal standards was used for the quantitative determination. The results showed that the optimized analytical method is suitable for the reliable determination of traces of benzo(a)pyrene in water, as the determination results were reproducible and within the specified criteria. We found an influence of the matrix, as the yields in the solvent were too high. Therefore, we prepared a calibration curve in the water matrix in which we met the criteria (the yields were between 70 % and 110 %). policiklični aromatski ogljikovodiki benzo(a)piren plinska kromatografija masni spektrometer ekstrakcija tekoče-tekoče polycyclic aromatic hydrocarbons benzo(a)pyrene gas chromatography mass spectrometer liquid-liquid extraction true true false [A. Štrakl] Slovenski jezik Angleški jezik Magistrsko delo/naloga 2024-09-07 19:39:33 2024-09-26 13:37:57 2025-01-11 03:09:05 0000-00-00 00:00:00 2024 0 Maribor 0 Maribor 1 spletni vir (1 datoteka PDF (IX, 71 f.)) 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 543.5:[543.38:547.6](043.2) 221660419 MAG_Strakl_Anja_2024.pdf MAG_Strakl_Anja_2024.pdf 1 6B66A629767C216E7627B8563DE429AC 3c082b18be5d010fe118d0bb23c97c48601cb0d545f1454f2bf87c58643a2072 2ab180a2-7b76-11ef-b03d-00155d000105 https://dk.um.si/Dokument.php?lang=slv&id=185906 Fakulteta za kemijo in kemijsko tehnologijo 0 0 0