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Chlorpyrifos (CPS) is a toxic pesticide present in several pesticide formulations, with low degradability by natural processes. The degradation leads to the toxic metabolite chlorpyrifos-oxon (CPO). The analytical techniques used for the CPS and CPO analysis, like UPLC-PDA and GC-MS, are accurate but also expensive and time consuming, and they need sample pretreatment. In the search of a more rapid and simple analytical procedure, atmospheric solids analysis probe with mass spectrometry (ASAP-MS) was optimized for the determination of CPS and CPO in apples (Malus domestica „Idared”). The identification of the analytes was based on protonated ion and isotopic pattern, while the quantification was based on peak intensities. The obtained results were confirmed by re-validated UPLC-PDA and GC-MS techniques. CPS and CPO concentrations determined by ASAP-MS and UPLC-PDA showed moderate discrepancies (on average by 10–20%), thus demonstrating that ASAP-MS can be a semiquantitative tool for the quantification of these compounds. As additional goal of this work, the efficiency of a gamma irradiation treatment to remove CPS and CPO from apples was tested by analyzing their content before and after the irradiation: 89–99% of CPS and CPO were degraded with doses of 3.5–3.8 kGy and 66–72 h of irradiation per sample. Identical degradation results were obtained by UPLC-PDA and ASAP-MS, indicating that the latter technique is well suitable to rapidly check pesticide degradation in apples. © 2019 Slovensko Kemijsko Drustvo. All Rights Reserved.

Predmet ove disertacije je proučavanje reakcija hidrolize aluminijum(III)-jona i reakcija kompleksiranja aluminijum(III)-jona i fluorohinolona (HQ) (fleroksacina, ciprofloksacina i moksifloksacina). U okviru disertacije određena je specijacija u rastvorima aluminijum(III)-jona i rastvorima aluminijum(III)-jona i fluorohinolona (HQ) sa ciljem boljeg razumevanja farmako i toksikokinetike fluorohinolonskih antibiotika u prisustvu lekova na bazi aluminijuma (antacidi, vakcine, dijalizatni rastvori). Proučavanja su vršena elektrosprej masenom spektrometrijom, (ESI MS), tandem masenom spektrometrijom (MS/MS) i masenom spektrometrijom, gde je jonizacija potpomognuta laserskom desorpcijom iz matriksa (MALDI MS). Proučavanjem navednih sistema, pomenutim eksperimentalnim tehnikama i kompjuterskom obradom podataka, korišćenjem programa Hyss 2006 i modela veštačkih neuronskih mreža (AAN) dobijeni su sledeći rezultati: Pri proučavanju hidrolize aluminijuma vrste identifikovane u rastvorima aluminijum(III)-jona, koncetracije 0,03 do 5,0 mmol/dm3, su vrste sa naelektrisanjem +1, +2 i +3, formirane u opsegu pH od 3-6. Monomerne i dimerne vrste su dominantne do pH 3,8. ESI MS spektri ukazuju na formiranje malih polimernih vrsta (Al3–Al5) na pH 4,8. Sa povećanjem pH i koncetracije aluminijum(III)-jona identifikuju se srednji polimeri (Al6–Al10). Daljim povećanjem pH i koncentracije aluminijum(III)-jona nastaju viši polimeri (Al11–Al13). Viši polimeri su privremene vrste koje postoje relativno kratko vreme nakon pripreme rastvora. Na pH oko 6,4 počinje formiranje taloga. Rezultati dobijeni ESI masenom spektrometrijom su u saglasnosti sa rezultatima dobijenim 27 Al NMR spektroskopijom i potenciometrijom., Th is dissertation comprises investigation of hydrolysis aluminum(III)-ion and aluminum(III)-ion and fl uoroquinolones (FQLs) family members (fl eroxacin, ciprofl oxacin and moxifl oxacin) complexation reactions. Within present study it is determined speciation in solutions of aluminum(III)-ion and in solutions of aluminum(III)-ions and fl uoroquinolones (FQLs) in aim to better understand pharmacotherapy and toxicokinetics of fl uoroquinolones antibiotics in the presence of aluminum-based drugs (antacids, vaccines, solutions for dialysis). So the solutions were investigated by electrospray mass spectrometry (ESI MS), tandem mass spectrometry (MS/MS) and mass spectrometry with matrix-assisted laser desorption ionization (MALDI MS). Investigation or these systems, using the above mentioned experimental techniques and computer processing data by using Hyss 2006 soft ware and artifi cial neural network (AAN) model gave the following results: Th e hydrolysis of aluminum(III)-ion have been investigated in the solutions of concentration level 0,03 to 5,0 mmol/dm3, in the pH range 3 to 6. Th e species with electric charge +1, +2 and +3, formed in this conditions. Monomeric and dimeric species were dominant until the pH value of 3,8. ESI MS spectra indicate the formation of small polymeric species (Al3-Al5) at pH 4,8 value. With the increase pH and concentrations values of aluminum(III)-ion, it was identifi ed intermediate polymers (Al6-Al10). With further increase in pH and the concentration of aluminum(III)-ion, higher polymers (Al11-Al13) were generated. Higher polymers are species that are relatively short period of time existing. At a pH of about 6,4 the sludge formed. Th e results obtained by ESI MS spectra are in good agreement with the results obtained by 27Al NMR spectroscopy and by potentiometry.

Water quality from three conventional river water treatment plants (Zlatibor, Rzav and Cerovica brdo) using aluminum sulphate (alum)as coagulant in the region of Uzice was investigated in the period 2005-2006. The concentrations of aluminium (Al) in studied samples (drinking water, river and soil) were determined by inductively coupled plasma optical emission (ICP-OES) spectrometry and validated by atomic absorption spectrometry (AAS) and DC-Arc plasma. Similar results were obtained by employed analytical methods. The total residual aluminum concentrations were in the range of 0.02 to 0.26 mg AN controlled by pH at investigated treatment plants. Concentrations of residual aluminium exceeding the public health goal standards were recorded in spring (March, April) during snow-melt episodes in this area. The discharge water after breed treatment with alum coagulant into the stream rivers did not cause any changes of the natural equilibrium of this ecosystem as well as indirectly the category of these rivers downstreams.

The complex formation between L-histidine (HHis) and aluminum(III) ion in water solutions was studied by UV spectrophotometric and 27-Al NMR measurements at 298 K. UV spectra were measured on solutions in which the total concentration of histidine was from 15.0 to 50.0 mmol/dm(3) and the concentration ratio of histidine to aluminum was varied from 3 : 1 to 10 : 1 in the pH range between 4.2 and 6.0. The spectra were taken in the wavelength interval 240 - 340 nm. Nonlinear least-squares treatment of the spectrophotometric data indicates the formation of the complexes Al(HHis)(3+), Al(His)(2+), Al(HHis)His(2+), and Al-2(OH)His(4+) with the overall formation constants beta(p,q,r): log beta(1,1,1) = 11.90 +/- 0.04, log beta(1,1,0) = 7.25 +/- 0.08, log beta(1,2,1) = 20.1 +/- 0.1, and log beta(2,1,1) = 5.92 +/- 0.12 ( p, q, r are stoichiometric indices for metal, ligand, and proton, respectively). Al-27-NMR spectra were taken on solutions with the concentration of aluminum 50 mmol/dm(3) and that of histidine 250 mmol/dm(3). In the pH interval 5.0 - 6.1, two resonances at 9.5 ppm and 12.0 ppm were assigned to Al(HHis)(2+) and Al( HHis)(His)(2+) (or Al(OH)(HHis)(2)(2+)), respectively.