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Öğe An accurate and sensitive determination of selected pesticides in mixed fruit juice samples using the combination of a simple and efficient microextraction method and GC-MS with a matrix matching calibration strategy(Royal Soc Chemistry, 2024) Bodur, Sueleyman; Tutar, Bahar Karademir; Tutar, Omer Faruk; Bakirdere, SezginPesticides have been used on several fruits, vegetables and cereals to control harmful organisms in order to increase the quality of products; however, these substances cause serious health effects. Therefore, an accurate and sensitive analytical method should be developed for the determination of pesticides to evaluate their toxicity. In this study, an efficient microextraction strategy was applied to preconcentrate eight different selected pesticides from mixed fruit juice samples prior to gas chromatography-mass spectrometry detection. All significant parameters such as spraying number, extraction solvent type, sample volume and mixing type/period belonging to the developed extraction method were elaborately optimized to get low detection limits. After the optimization studies, system analytical performance studies were carried out and limit of detection (LOD) values varied from 0.04 mu g /kg-1 to 1.99 mu g kg-1 (mass based) for the selected analytes. Under the optimum experimental conditions, spiking recovery experiments were performed in the mixed fruit juice samples to evaluate the applicability and accuracy of the proposed method. The recovery results were recorded in the range of 81.4-123.5% with acceptable standard deviations by applying a matrix matching calibration strategy. The proposed analytical method can be used for the qualitative and quantitative determination of selected pesticides in the mixed fruit juice samples and can also be applied to other fruit juice samples using a matrix matching calibration strategy. A simple and efficient microextraction method was proposed to preconcentrate eight different pesticides from mixed fruit juice samples prior to GC-MS measurement.Öğe Assessment of external calibration, internal standard calibration and quadruple isotope dilution strategies for the determination of acrylamide in wastewater samples after LC-MS/MS quantification(Elsevier, 2023) Yazici, Elif; Bodur, Suleyman; Erarpat, Sezin; Arslan, Ulas Emre; Bakirdere, SezginAcrylamide is a possible neurotoxicant and carcinogen compound and its common usage in various industrial processes causes acrylamide contamination in environmental bodies. For this purpose, there is an increasing demand to develop an accurate and selective analytical method for the determination of acrylamide. In the scope of this study, external calibration (EC), internal standard calibration (ISC) and quadruple isotope dilution (ID4) strategies were compared to each other in terms of accuracy and precision. After the evaluation of these methods, liquid chromatography - quadruple isotope dilution - tandem mass spectrometry (LC-ID4-MS/MS) as a highly accurate and precise analytical approach was proposed to quantify acrylamide in wastewater samples. Several parameters for LC system such as sample injection volume, mobile phase type/composition and mobile phase flow rate were elaborately optimized to enhance peak shape and signal to noise ratio (S/N) belonging to the analyte. Under the optimum chromatographic and mass determination conditions, system analytical perfor-mance study was performed to determine dynamic range and limit of detection/quantitation (LOD and LOQ). LOD and LOQ values of the proposed LC-MS/MS method for the analyte were calculated as 1.18 and 3.93 mu g/kg; respectively. After the system analytical performance study, the spiking experiments in wastewater samples were carried out for the evaluation of accuracy and applicability of LC-MS/MS method. For wastewater samples, percent recovery results with their percent relative standard deviations (%RSD) obtained from EC, ISC and ID4 strategies were 115.8-177.8% (+/- 1.2-11.4%), 94.5-117.7% (0.3-4.7%) and 99.6-100.9% (0.4-1.7%); respec-tively. These results prove the superiority of ID4 strategy with regards to accuracy and precision of the results.Öğe Cadmium determination at trace levels in lake water samples by cold vapor generation-atomic absorption spectrometry after magnetic dispersive solid phase extraction(Springer Int Publ Ag, 2023) Bodur, Suleyman; Erarpat, Sezin; Kayin, Inci; Bakirdere, SezginThis study established an analytical method based on manganese ferrite based magnetic dispersive solid phase extraction (MDSPE) before cold vapor generation-atomic absorption spectrometry (CVG-AAS) for the determination of cadmium at trace levels in lake water samples collected from Horseshoe Island, Antarctica. Manganese ferrite nanoparticles were synthesized to be used as an adsorbent in the MDSPE method. Different MDSPE and CVG parameters were fixed to their optimum values after univariate optimization approach. Under the optimum conditions, analytical performance of the developed MDSPE-CVG-AAS method was evaluated and its applicability/accuracy was determined by recovery experiments. Twelve different lake water samples collected from Horseshoe Island, Antarctica were analyzed. Matrix matching calibration strategy was used to eliminate possible matrix effects arising from the lake water samples. Good recovery results (93.2-112.5%) were obtained from the spiked samples that indicated the method suitability to real samples.Öğe Deep eutectic solvents for the determination of endocrine disrupting chemicals(Elsevier, 2024) Chormey, Dotse Selali; Zaman, Buse Tugba; Kustanto, Tulay Borahan; Bodur, Sezin Erarpat; Bodur, Suleyman; Er, Elif Ozturk; Bakirdere, SezginThe harmful effects of endocrine disrupting chemicals (EDCs) to humans and other organisms in the environment have been well established over the years, and more studies are ongoing to classify other chemicals that have the potential to alter or disrupt the regular function of the endocrine system. In addition to toxicological studies, analytical detection systems are progressively being improved to facilitate accurate determination of EDCs in biological, environmental and food samples. Recent microextraction methods have focused on the use of green chemicals that are safe for analytical applications, and present very low or no toxicity upon disposal. Deep eutectic solvents (DESs) have emerged as one of the viable alternatives to the conventional hazardous solvents, and their unique properties make them very useful in different applications. Notably, the use of renewable sources to prepare DESs leads to highly biodegradable products that mitigate negative ecological impacts. This review presents an overview of both organic and inorganic EDCs and their ramifications on human health. It also presents the fundamental principles of liquid phase and solid phase microextraction methods, and gives a comprehensive account of the use of DESs for the determination of EDCs in various samples.Öğe Determination of copper in rose tea samples using flame atomic absorption spectrometry after emulsification liquid-liquid microextraction(Elsevier Sci Ltd, 2024) Kartoglu, Bedrihan; Bodur, Suleyman; Zeydanli, Damla; Gover, Tugce; Ozaydin, Ecem; Bakirdere, Emine Gulhan; Bakirdere, SezginRose tea infusion has gained popularity worldwide due to its health benefits. However, it is known that tea plants can be contaminated with heavy metals including copper. Hence, an accurate and applicable analytical method namely emulsification liquid-liquid microextraction based deep eutectic solvent - flame atomic absorption spectrometry (ELLME-DES-FAAS) was proposed to determine copper at trace levels in rose tea samples. Under the optimum experimental conditions, analytical figures of merit for the developed method were examined, and dynamic range, limit of detection (LOD) and limit of quantification (LOQ) were found to be 5.07-246.61 mu g/kg (mass-based) with 0.9992 coefficient of determination, 2.50 mu g/kg and 8.32 mu g/kg, respectively. A matrix matching calibration strategy was employed to boost recovery results, and the acceptable recovery results were recorded between 95.9 % and 118.4 %. According to recovery results, the developed analytical method can be safely employed to determine the concentration of copper in rose tea samples accurately.Öğe Determination of phenytoin at trace levels in domestic wastewater and synthetic urine samples by gas chromatography-mass spectrometry after its preconcentration by simple liquid-phase microextraction(Springer, 2024) Bodur, Sezin Erarpat; Ayan, Gizem Nur; Bodur, Suleyman; Gunkara, Omer Tahir; Bakirdere, SezginThis work presents a sensitive and accurate analytical method for the determination of phenytoin at trace levels in domestic wastewater and synthetic urine samples by gas chromatography-mass spectrometry (GC-MS) after the metal sieve-linked double syringe liquid-phase microextraction (MSLDS-LPME) method. A metal sieve was produced in our laboratory in order to disperse water-immiscible extraction solvents into aqueous media. Univariate optimization studies for the selection of proper extraction solvent, extraction solvent volume, mixing cycle, and initial sample volume were carried out. Under the optimum MSLDS-LPME conditions, mass-based dynamic range, limit of quantitation (LOQ), limit of detection (LOD), and percent relative standard deviation (%RSD) for the lowest concentration in calibration plot were figured out to be 100.5-10964.2 mu g kg-1, 150.6 mu g kg-1, 45.2 mu g kg-1, and 9.4%, respectively. Detection power was improved as 187.7-folds by the developed MSLDS-LPME-GC-MS system while enhancement in calibration sensitivity was recorded as 188.0-folds. In the final step of this study, the accuracy and applicability of the proposed system were tested by matrix matching calibration strategy. Percent recovery results for domestic wastewater and synthetic urine samples were calculated as 95.6-110.3% and 91.7-106.6%, respectively. These results proved the accuracy and applicability of the proposed preconcentration method, and the obtained analytical results showed the efficiency of the lab-made metal sieve apparatus.Öğe A powerful combination of liquid chromatography-triple quadrupole mass spectrometry and quadruple isotope dilution strategy for the determination of fenuron at trace levels in river water, stream water and fruit juice samples(Academic Press Inc Elsevier Science, 2023) Bodur, Sueleyman; Erarpat, Sezin; Gunkara, Omer Tahir; Bakirdere, SezginAn accurate, sensitive, and rapid analysis methodology for the determination of fenuron at ultratrace levels in river water, stream water and fruit juice samples was developed based on quadruple isotope dilution (ID4) and liquid chromatography-triple quadrupole mass spectrometry (LC-MS/MS) system. Fenuron-d6 as isotopically labelled material (ILM) was synthesized in our laboratory to apply the ID4 method. Optimization studies were performed to find experimental conditions for the separation and detection of fenuron at trace levels. Analytical performance parameters such as limit of detection (LOD), limit of quantitation (LOQ) and linear range were determined by external calibration strategy. LOD and LOQ values for the analyte were found at ppt levels and a wide linear range was obtained in the range of 0.11 - 492.4 & mu;g/kg. Recovery studies were also carried out for water and fruit juice samples to test applicability and accuracy of the developed LC-MS/MS system. ID4 strategy was applied to the selected samples to increase accuracy of the developed method and tolerate high matrix effects for fruit juice samples. According to high percent recoveries and low relative standard deviation values, the developed LC-ID4-MS/MS system was proven as an accurate, precise and sensitive analytical method for the quantification of fenuron at trace levels.Öğe Spray assisted preconcentration method combined with HPLC-Continuous flow hydride generation-FAAS for inorganic arsenic speciation in olive oil samples(Academic Press Inc Elsevier Science, 2023) Bodur, Sueleyman; Erarpat, Sezin; Tutar, Omer Faruk; Bakirdere, SezginSpeciation analysis of arsenic in edible oils is an important topic in terms of the assessment of its risks for human health and the quality of edible oils. In this study, high performance liquid chromatography - continuous flow hydride generation - flame atomic absorption spectrometry (HPLC-CFHG-FAAS) system after vortex assisted reverse phase spray-based fine droplet formation liquid phase microextraction (VA-RP-SFDF-LPME) method was proposed to qualify/quantify arsenite and total arsenic. Limit of detection (LOD) and limit of quantification (LOQ) for arsenite were calculated as 2.86 & mu;g kg-1 (as As) and 9.52 & mu;g kg-1 (as As), respectively. After the extraction/preconcentration process, a prereduction was carried out in the presence of 0.010 mol/L HCl (con-taining 0.39% L-cysteine) with heat (90 & PLUSMN; 5 oC) for the determination of total arsenic content while arsenite was directly determined via the developed system. Recovery for arsenite and total inorganic arsenic were in the range of 91.5 - 120.4% and 90.0 - 104.4%, respectively. The developed method is proposed for the analysis of olive oil samples containing inorganic arsenic species. This is the first study to carry out the inorganic arsenic speciation in olive oil by HPLC-CFHG-FAAS system after the preconcentration of the species by the VA-RP-SFDF-LPME system. For the matrix including arsenite and arsenate, the developed method can be safely used to find the concentration of both species accurately.Öğe Synthesis of Isotopic Labelled Paracetamol Benzoate-d3 and Its Application in the Determination of Paracetamol(Wiley-V C H Verlag Gmbh, 2023) Demirel, Rabia; Erarpat, Sezin; Bodur, Suleyman; Gunkara, Omer Tahir; Bakirdere, Sezgin; Turak, FatmaThis study proposed a precise/accurate analytical method for the paracetamol (PCT) determination in human serum/urine matrices. PCT was simultaneously derivatized and preconcentrated by dispersive liquid-liquid microextraction (DLLME). Benzoyl chloride dissolved in dichloromethane was used as derivatization agent in the extraction solvent. Quadruple isotope dilution (QID) method with three calibration mixtures (A*B-x, x=1,2,3) and one sample mixture (AB) was performed to enhance the method accuracy and precision. In our research laboratory, paracetamol benzoate-d3 (PCT benzoate-d3) was synthesized and used as isotopically labelled substance (B) to conduct QID method. After the combination of QID and DLLME-GC-MS systems, percent recovery results for human serum/urine matrices were found to be 99.3-101.0 % and 98.8-99.9 %, respectively.Öğe Trace determination of nickel in water samples by slotted quartz tube-flame atomic absorption spectrometry after dispersive assisted simultaneous complexation and extraction strategy(Springer, 2018) Özzeybek, Gözde; Alacakoç, Bihter; Kocabaş, Mehmet Yusuf; Bakirdere, Emine Gülhan; Chormey, Dotse Selali; Bakirdere, SezginThis study presents a new method for the determination of nickel in aqueous samples by slotted quartz tube-flame atomic absorption spectrometry (SQT-FAAS) after a dispersive assisted simultaneous complexation and extraction (DASCE) process. Synthesized ligand was directly dissolved in the extraction solvent to eliminate the complex formation step prior to the extraction. All parameters of the SQT-FAAS and DASCE method were systematically optimized to improve the detection power of nickel for trace determinations. Under the optimum experimental conditions, the optimized method (DASCE-SQT-FAAS) recorded 137-fold enhancement in detection power over the conventional FAAS. The limits of detection and quantification were determined to be 1.6 mu g/L and 5.2 mu g/L, respectively. The calibration plot was linear over a wide concentration range and the precision for replicate measurements was appreciably high. Nickel was not detected in five different water samples but spiked recovery tests for three samples yielded results that were close to 100%, confirming the method's accuracy and applicability to the matrices tested.
