Razvoj ekstrakcije na trdno fazo z nepolarnimi interakcijami za izbrana onesnaževala

Poljanšek, Anja (author), Prosen, Helena (mentor)

V vsakdanjem življenju in v industriji se pogosto uporabljajo številne kemikalije. Številne med njimi lahko pristanejo v okolju, kamor pridejo z izpusti mestne ali industrijske odpadne vode, kmetijske in industrijske dejavnosti, itd. Prisotne so lahko tudi v površinskih vodah, ki predstavljajo življenjsko okolje številnim organizmom. Kemijsko onesnaženje površinskih vod povzroča akutno in kronično toksičnost za vodne organizme in kopičenje v ekosistemu, ogroža pa tudi zdravje ljudi. Zaradi tega je pomembno, da razvijamo metode, s katerimi bi lahko ta onesnaževala odstranili iz okolja. Razvijala sem ekstrakcijo organskih onesnaževal, ki spadajo v skupine zdravil, pesticidov, kozmetičnih sredstev, prehranskih aditivov in industrijskih kemikalij. Metodo sem najprej optimizirala pri višjih koncentracijah analitov, kjer sem za analizo in separacijo analitov uporabila UHPLC-DAD. Ker se analiti v površinskih vodah pojavljajo v tako nizkih koncentracijah, da jih metoda UHPLC-DAD ne zaznava, sem pri koncentracijah analitov, kakršne se pojavljajo v okolju, uporabila UHPLC-MS/MS. Metodo ekstrakcije na trdno fazo sem optimizirala, da sem dobila primerne pogoje. Izmed vseh uporabljenih reverzno-faznih kolon z različnimi sorbenti sem izbrala kolono Oasis HLB (150 mg), vzorce pa sem nakisala na pH 2,5. Največji volumen vzorca, ki sem ga nanesla, je bil 260 mL. Analite sem eluirala z 12 mL elucijskega topila, za kar sem uporabila 7 mL MeOH, 3 mL MeOH/aceton (8:2) in 2 mL MeOH/aceton (2:8). Po sušenju sem ekstrakt rekonstituirala z 0,4 mL rekonstitucijskega topila, in sicer z 320 µL MeOH in 80 mL MQ. Končno linearno območje ekstrakcijske metode v kombinaciji z UHPLC-MS/MS metodo je bilo med 0,1 µg/L in 10 µg/L, R2 pa so bili za vse analite nad 0,990. Rezultati analiz so bili ponovljivi za devet določanih onesnaževal.

• Language: Slovenian
• Keywords: organska onesnaževala, površinske vode, ekstrakcija na trdno fazo (SPE), reverzna faza (RP)
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: FKKT - Faculty of Chemistry and Chemical Technology
• Year: 2023
• PID: 20.500.12556/RUL-148950
• COBISS.SI-ID: 165262339
• Publication date in RUL: 01.09.2023

Secondary language

• Language: English
• Title: Development of solid phase extraction with non-polar interactions for selected pollutants

Abstract

In everyday life and in the industry, numerous chemicals are frequently used. Many of them can end up in the environment through the discharge of municipal or industrial wastewater, agricultural and industrial activities, etc. They can also be present in surface waters, which provide a habitat for numerous organisms. Chemical pollution of surface waters causes acute and chronic toxicity to aquatic organisms and accumulates in the ecosystem, posing a threat to human health as well. Therefore, it is important to develop methods for removing these pollutants from the environment. I have been developing the extraction method for organic pollutants belonging to groups such as pharmaceuticals, pesticides, cosmetics, food additives, and industrial chemicals. Firstly, I optimized the method at higher analyte concentrations using UHPLC-DAD for analysis and separation of analytes. Since analytes in surface waters occur in such low concentrations that UHPLC-DAD cannot detect them, I used UHPLC-MS/MS at environmentally relevant concentrations of analytes. I optimized the solid-phase extraction method to obtain suitable conditions. Among all the used reverse-phase columns with different sorbents, I selected the Oasis HLB column (150 mg), and I acidified the samples to pH 2.5. The maximum sample volume applied was 260 mL. I eluted the analytes with 12 mL of elution solvent, using 7 mL of MeOH, 3 mL of MeOH/acetonitrile (8:2), and 2 mL of MeOH/acetonitrile (2:8). After drying, the samples were reconstituted with 0.4 mL of reconstitution solvent, specifically 320 µL of MeOH and 80 mL of MQ water. The final linear range of extraction method in combination with UHPLC-MS/MS method was between 0.1 µg/L and 10 µg/L, with R2 values above 0.990 for all analytes. The results of analyses were reproducible for nine specified pollutants.

• Keywords: organic pollutants, surface waters, solid-phase extraction (SPE), reverse phase (RP)