| Abstract | Napredak farmaceutske industrije, dostupnost raznih farmaceutika na tržištu, porast broja stanovnika te nedovoljno učinkoviti sustavi za obradu otpadnih voda doveli su do pojave farmaceutika u okolišu, konkretno u vodi i tlu. Farmaceutici su u okolišu prisutni u malim količinama, ali i te male količine dovoljne su za nepovoljan utjecaj farmaceutika na zdravlje ljudi, biljaka i životinja. Zbog svega navedenog, radi se na pronalaženju metode koja će biti prihvatljiva za uklanjanje farmaceutika iz vode. U ovom diplomskom radu ispitivana je ekstrakcija smjese 12 farmaceutika (amoksicilin, atenolol, β-estradiol, deksametazon, diazepam, diklofenak, karbamazepin, ofloksacin, prokain, sulfametazin, sulfametoksazol i torasemid) iz vode pomoću Fe3O4/SiO2/TiO2 nanokompozitnih magnetnih čestica. Ovaj magnetni sorbens novi je tip sorbensa koji se primjenjuje za magnetsku ekstrakciju čvrstom fazom. Ovim radom prvo su određeni optimalni uvjeti sorpcije ispitivane smjese farmaceutika na korištene magnetne čestice nakon čega se pristupilo određivanju otapala za eluiranje kao i potrebnog volumena otapala za eluiranje smjese farmaceutika s magnetnih čestica. U tu svrhu ispitana je kinetika sorpcije, određena je optimalna početna koncentracija smjese farmaceutika te optimalno vrijeme potrebno za sorpciju, optimalan pH, temperatura, ionska jakost te masa magnetnih čestica. Određena optimalna početna koncentracija smjese farmaceutika (pH vrijednosti 6, bez ionske jakosti) je 1 mg/L, vrijeme mućkanja 1 sat pri 25 °C na masi od 20 mg magnetnih čestica. Određeni optimalni uvjeti primijenjeni su na sorpciju iste smjese farmaceutika na magnetne čestice s otiskom sulfametoksazola. Općenito, na magnetnim česticama s otiskom sulfametoksazola postignuta je bolja učinkovitost sorpcije i to posebice molekule sulfametoksazola što je bilo očekivano. Nakon sorpcije ispitana je i desorpcija sorbiranih farmaceutika s površine magnetnih čestica eluiranjem s različitim otapalima (metanol, etanol, acetonitril, izopropanol, aceton, voda, etil-acetat, heksan i diklormetan). Najboljim otapalom za eluiranje pokazao se metanol i to postupkom eluiranja u tri koraka; najprije s 1 mL, zatim s 2x 2 mL. Odabrano otapalo primijenjeno je i za desorpciju smjese farmaceutika s magnetnih čestica s otiskom sulfametoksazola gdje su također postignuta dobra iskorištenja. Kvantitativno određivanje učinkovitosti koraka sorpcije i desorpcije ostvareno je primjenom je tekućinske kromatografije visoke djelotvornosti s DAD detektorom (HPLC-DAD). |
| Abstract (english) | The progress of the pharmaceutical industry, the availability of various pharmaceuticals in pharmacies, the increase in the population, and insufficiently efficient wastewater treatment systems have led to the presence of pharmaceuticals in the environment, especially in water and soil. Pharmaceuticals are present in the environment only in small quantities, but even these small quantities are enough to affect the health of himans, plants and animals.
For these reasons, we are working to find an acceptable method of removing pharmaceuticals from water. In this work, the extraction of a mixture of 12 pharmaceuticals (amoxicillin, atenolol, β- estradiol, dexamethasone, diazepam, diclofenac, carbamazepine, ofloxacin, procaine, sulfamethazine, sulfamethoxazole and torasemide) from water was studied using Fe3O4/SiO2/TiO2 nanocomposite magnetic particles. This magnetic sorbent is a new type of sorbent used for magnetic solid-phase extraction. Firstly, the optimal conditions for the sorption on the investigated pharmaceutical mixture on the used magnetic particles were determined. Subsequently, the solvent for the elution of the pharmaceutical mixture from the magnetic particles and the required volume of the elution solvent were determined. For this purpose, the kinetics of sorption were investigated, the optimal initial concentration of the pharmaceutical mixture and the optimal time required for sorption, the optimal pH, the temperature, the ionic strength and the mass of the magnetic particles were determined.
The determined optimal initial concentration of the pharmaceutical mixture (pH 6, without ionic strength) is 1 mg/L, shaking time 1 hour at 25 °C with mass of 20 mg magnetic particles. Certain optimal conditions were applied to the sorption of the same pharmaceutical mixture on magnetic particles with sulfamethoxazole imprinted polymer. In general, better sorption efficiency was obtained on magnetic particles with sulfamethoxazole imprinted polymer, especially for sulfamehoxazole, which was expected. After sorption, the desorption of the sorbed pharmaceuticals from the surface of the magnetic particles was tested by elution with different solvents (methanol, ethanol, acetonitrile, isopropanol, acetone, water, ethyl acetate, hexane and dichloromethane). Methanol proved to be the best eluent, with a three-step elution process; first with 1 mL, then 2x 2 mL. The selected solvent was also used for the desorption of a mixture of pharmaceuticals with magnetic particles imprinted with sulfamethoxazole, where good yields were also obtained. The quantitatively determination of the efficiency of the sorption and desorption steps was carried out using high-performance liquid chromatography with DAD detector (HPLC-DAD). |
