Optimizacija metode DMSPE-HPLC-DAD za določanje farmacevtskih učinkovin v površinskih vodah

Mileva, Martina (author), Prosen, Helena (mentor)

V diplomskem delu sem s preizkušanjem različnih tipov sorbentov ter optimizacijo ekstrakcijskih in desorpcijskih pogojev razvila metodo DMSPE za uspešno ekstrakcijo štirih farmacevtskih onesnaževal iz vodne matrice. Začela sem s eksperimentom, pri katerem sem poskusila različne sorbente pri različnih pH. Kod najbolj učinkovit sorbent se je izkazal C18 Supelco. V naslednjem koraku sem temu sorbentu dodala še anionsko izmenjavalni sorbent SAX, s čemer sem izboljšala izkoristke. Delala sem v štirih različnih pH območjih in kot najbolj ustrezni medij se je izkazal šibko kisli pH 4,2. V okviru mojega diplomskega dela sem tudi želela preveriti vpliv mase sorbenta na ekstrakcijo, hkrati pa določiti najbolj učinkovito razmerje mase med sorbentom C18 in anionsko izmenjavalnim sorbentom. Še en cilj optimizacije je bil skrajšati celotni čas analiznega postopka, oziroma skrajšati čas ekstrakcije, stresanja in desorpcije. Edini korak, ki se je dal časovno skrajšati za 15 min, je bil korak stresanja. Naslednji izziv je bil izbrati desorpcijsko topilo, pri čemer sem poskusila različna topila in mešanic topil v različnih razmerjih, najboljši rezultat je dal acetonitril z 1 % metanojske kisline. V zadnjem koraku tega dela sem uporabila realne vzorce morske in rečne vode, da bi proučevala matrični učinek na ekstrakcijo. Ekstrakte sem analizirala z HPLC-DAD. Končni izkoristki določevanih spojin so znašali med 55 % in 90 %, RSD pa so za vse analite bili manjši od 6%.

• Language: Slovenian
• Keywords: DMSPE, farmacevtske učinkovine, HPLC-DAD, optimizacija metode, novodobna onesnaževala
• Work type: Bachelor thesis/paper
• Organization: FKKT - Faculty of Chemistry and Chemical Technology
• Year: 2024
• PID: 20.500.12556/RUL-161290
• Publication date in RUL: 09.09.2024

Secondary language

• Language: English
• Title: Optimization of DMSPE-HPLC-DAD method for the determination of pharmaceuticals in surface water

Abstract

In my thesis I developed a DMSPE method for the successful extraction of four pharmaceutical pollutants from water matrix by testing different types of sorbents and optimising the extraction and desorption conditions. I started with an experiment where I tried different sorbents at different pH. The most effective sorbent was found to be C18 Supelco. In the next step, I added an anion exchange sorbent SAX to that sorbent to improve the recoveries. I worked in four different pH ranges and a weakly acidic pH 4.2 proved to be the most suitable medium. As part of my thesis work, I also wanted to check the effect of sorbent mass on extraction, while determining the most efficient mass ratio between C18 sorbent and anion exchange sorbent. Another aim of this optimisation method was to reduce the overall time of the analytical procedure, or rather to reduce the extraction, shaking and desorption time. The only step that could be reduced by 15 min was the shaking step. The next challenge was to choose the desorption solvent, and I tried different solvents and solvent mixtures in different ratios, the best results were achieved with acetonitrile with 1% methanoic acid. In the final step of this work, I used real samples of seawater and river water to study the matrix effect on extraction. The extracts were analysed by HPLC-DAD. The final recoveries of the compounds ranged between 55% and 90% and the RSD were less than 6% for all analytes.

• Keywords: DMSPE, pharmaceuticals emergent pollutants, HPLC-DAD, method optimization