Özdoğan, Nizamettin | Kapukıran, Fatih | Öztürk Er, Elif | Bakırdere, Sezgin

Article | 2019 | Environmental Monitoring and Assessment191 ( 6 )

The emergence of magnetic materials has opened up doors to numerous applications including their use as sorbents for preconcentration of trace elements. Magnetic materials exhibit many unique advantages in sample preparation such as easy separation from the sample, high preconcentration factor, and short operation period. In the present study, magnetic cobalt material was synthesized, characterized, and used as an effective sorbent in a solid phase extraction process. Experimental variables of the extraction process including pH and volume of buffer solution, eluent concentration and volume, mixing type and period, and sorbent amoun . . .t were optimized to achieve maximum extraction efficiency. Instrumental variables of flame atomic absorption spectrophotometry and the type of slotted quartz tube were also investigated. Under the optimum conditions, the combined method provided a wide linear range between 50 and 200 ng/mL with detection and quantification limits of 15.4 ng/mL and 51.3 ng/mL, respectively. Relative standard deviations of the proposed method were less than 5.0% and a high enrichment factor of 86.7 was obtained. The proposed method was successfully applied to soil samples for the determination of trace tellurium. © 2019, Springer Nature Switzerland AG Daha fazlası Daha az

Kapukıran, Fatih | Fırat, Merve | Chormey, Dotse Selali | Bakırdere, Sezgin | Özdoğan, Nizamettin

Article | 2019 | Bulletin of Environmental Contamination and Toxicology102 ( 6 ) , pp.848 - 853

In this study, the detection power of a gas chromatography mass spectrometer (GC–MS) for procymidone and chlorflurenol was significantly enhanced using switchable solvent liquid phase microextraction (SS-LPME) as a preconcentration tool. This was achieved by a comprehensive optimization of significant parameters to the SS-LPME method such as switchable solvent amount, concentration and amount of sodium hydroxide, pH effect and mixing effect. The optimum experimental conditions obtained were used to determine analytical figures of merit for the analytes. The limits of detection obtained were 0.44 and 2.9 ng/mL for procymidone and chl . . .orflurenol, respectively. The optimum method was applied to water sampled from an irrigation canal and two wastewater samples. The samples were spiked at two concentrations and the percent recovery results obtained ranged between 86 and 115% for both analytes. The recovery results together with the low standard deviations recorded validated the method as accurate and precise. © 2019, Springer Science+Business Media, LLC, part of Springer Nature Daha fazlası Daha az

Özdoğan, Nizamettin | Kapukıran, Fatih | Mutluoğlu, Gülşen | Chormey, Dotse Selali | Bakırdere, Sezgin

Article | 2018 | Environmental Monitoring and Assessment190 ( 10 ) , pp.848 - 853

This study reports the optimization of a binary dispersive liquid-liquid microextraction method for the determination of iprodione, procymidone, and chlorflurenol by gas chromatography mass spectrometry. The study was aimed at using two extraction solvents to increase the extraction efficiency of all analytes. The binary solvents recorded results higher than the mono-solvents. After examining the effects of main experimental parameters and their interactions by analysis of variance, 200 µL of binary mixture (dichloromethane and 1,2-dichloroethane), 2.5 mL of ethanol, and 15 s vortex were obtained as optimum parameters. The detection . . . and quantification limits calculated for the analytes were found to be between 0.30–1.6 and 1.0–5.3 ng/mL, respectively. Enhancement in detection power calculated as a ratio of the binary extraction detection limit to the detection limit of direct GC-MS analysis was 105-, 214-, and 233-fold for chlorflurenol, iprodione, and procymidone, respectively. In order to check the accuracy of the developed method, recovery study was performed. Water sampled from a lake and two wastewater samples from treatment facilities were spiked at two concentrations, and the percent recovery calculated for the samples ranged between 87 and 116%. These results confirmed the suitability of the method to real samples for accurate determination of the analytes at trace levels. © 2018, Springer Nature Switzerland AG Daha fazlası Daha az