Browsing by Author "Aydin, Firat"

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Determination of hydroxymethylfurfural in Turkish honeys, pekmez (grape molasses), and jam samples by high-performance liquid chromatography with diode array detection
(Wiley Online Library, 2022) Elmastas, Ayhan; Aydin, Firat; Umaz, Adil; Kılınc, Ersin; Arslan, Yasin; aydin, Isil
Hydroxymethylfurfural (HMF) is a chemical contaminant that is not naturally present in carbohydrate-containing food samples. The HMF amounts were changed between 4.8 and 214.1 mg/kg in honey; between 7.8 and 204.0 mg/kg in pekmez (grape molasses); between 5.9 and 22.4 mg/kg in strawberry jam; between 6.0 and 65.4 mg/kg in apricot jam; and between 9.2 and 55.9 mg/kg in cherry found by HPLC. The linear calibration plot of HMF was ranged from 0.05 to 10.0 mu g/ml. The correlation coefficient was found to be 0.99997. LOD and LOQ values were found to be 12.0 and 40.0 ng/ml, respectively. According to the experimental results, HMF amounts of four honey samples, three pekmez (grape molasses) samples, one apricot jam, and one cherry jam for investigated samples were found to be higher than the permission amount of Turkish Food Codex. Novelty impact statement Based on experimental results in this study, if the honey is in a transparent package such as a glass, it should be stored in a dark environment. It would be healthier to prefer molasses produced by reliable brands at low temperatures under vacuum instead of molasses made with traditional methods in open boilers. Generally, since jams with high HMF amount have an overcooked or even burnt flavor, this is an extremely negative situation for consumers.
Determination of zinc in dried nuts by slotted quartz tube-flame atomic absorption spectrometry (SQT-FAAS) with citric acid-coated magnetic nanoparticle (CAMNP) based solid phase extraction (SPE)
(Taylor & Francis inc, 2025) Umaz, Kader; Umaz, Adil; Aydin, Isil; Aydin, Firat
This study reports a sensitive method for trace zinc using slotted quartz tube-flame atomic absorption spectrometry (SQT-FAAS) with citric acid-coated magnetic nanoparticle-solid phase extraction (CAMNP-SPE). To increase the efficiency, we univariately optimized the pH, buffer volume, CAMNP mass, eluent concentration and volume, mixing type and time, temperature, and interaction time. The study identified the limits of detection and quantification values for CAMNP-SPE-SQT-FAAS under the specified optimum conditions to be 12.30 and 41.00 mu g L-1, respectively. The newly developed method improved the detection power of traditional FAAS by 13.25 times. The findings of this study report a sensitive and accurate method to determine trace zinc in complex matrices.
Evaluation as time-dependent of pesticides applied in pre-harvest period of grown vegetables: removal of pesticide residues in the vegetables
(Taylor & Francis Online, 2022) Elmastas, Ayhan; Umaz, Adil; Pirinc, Vedat; Aydin, Firat
Pesticide use has benefits such as increasing the quality and amount of food required to sustain the human population. However, its harmful effects on the environment and human health are of great concern. The aim of this study was to evaluate concentrations as timedependent of the pesticide and the removal of pesticide residues in vegetable samples with the aid of the QuEChERS 2007.01 procedure. The analytical method has been validated according to SANTE/12682/2019. Good linearity (2.5–100 ng/mL, R2 > 0.99) was observed, and the recovery yields ranged from 94.76% to 104.03%, repeatability (RSDr) ranged from 2.33% to 4.59% and reproducibility (RSDwR) ranged from 4.06% to 8.40%. LOD and LOQ values were determined to be 3.00 ng/g and 10.00 ng/g, respectively. The grown tomato, eggplant and cucumber samples were sprayed with drugs against pests and diseases. Imidacloprid in the grown tomato, cucumber and eggplant samples was determined to be 0.026, 0.186 and 0.096 mg/kg, respectively. Trifloxystrobin was determined to be 0.102, 0.129 and 0.063 mg/kg, respectively. It was determined that pesticide residue in vegetable samples decreases by washing and peeling but does not disappear completely. The peeling process was determined to be more effective than washing. The concentration of pesticide residues in the shell part was found to be hight than in the whole product. Thus, it is important to consume vegetables with their skin peeled and to consume the unpeeled ones by washing them with water at least.
In situ atom trapping of Bi on W-coated slotted quartz tube flame atomic absorption spectrometry and interference studies
(PERGAMON-ELSEVIER SCIENCE LTD, 2013) Kilinc, Ersin; Bakirdere, Sezgin; Aydin, Firat; Ataman, O. Yavuz
Analytical performances of metal coated slotted quartz tube flame atomic absorption spectrometry (SQT-FAAS) and slotted quartz tube in situ atom trapping flame atomic absorption spectrometry (SQT-AT-FAAS) systems were evaluated for determination of Bi. Non-volatile elements such as Mo, Zr, W and Ta were tried as coating materials. It was observed that W-coated SQT gave the best sensitivity for the determination of Bi for SQT-FAAS and SQT-AT-FMS. The parameters for W-coated SQT-FAAS and W-coated SQT-AT-FAAS were optimized. Sensitivity of FAAS for Bi was improved as 4.0 fold by W-coated SQT-FAAS while 613 fold enhancement in sensitivity was achieved by W-coated SQT-AT-FAAS using 5.0 min trapping with respect to conventional FAAS. MIBK was selected as organic solvent for the re-atomization of Bi from the trapping surface. Limit of detection values for W-coated SQT-FAAS and W-coated SQT-AT-FAAS was obtained as 0.14 mu g mL(-1) and 0.51 ng mL(-1), respectively. Linear calibration plot was obtained in the range of 2.5-25.0 ng mL(-1) for W-coated SQT-AT-FAAS. Accuracy of the W-coated SQT-AT-FAAS system was checked by analyzing a standard reference material, NIST 1643e. (C) 2013 Elsevier B.V. All rights reserved.
An Investigation and Comparison of Concentration Change in Simulated Body Fluid Medium Conditions of the Calcium Element in 27 Different Salvia Species
(Istanbul Univ, Fac Pharmacy, 2023) Umaz, Adil; Aydin, Firat; Firat, Mehmet; Yener, Ismail; Ertas, Abdulselam; Elmastas, Ayhan
Background and Aims: In this study, calcium (Ca) element concentration changes of Salvia species in simulated body fluid (SBF) medium conditions were investigated and the results in these medium conditions were compared with each other.Methods: Salvia species samples were air-dried and ground into powder. Salvia species was prepared as a herbal tea. Pre-pared teas were left in three different SBF medium conditions. The samples were analyzed using Flame Atomic Absorption Spectroscopy (FAAS) method to determine the Ca absorptions. Also, a correlation analysis of the results obtained in three different SBF medium conditions and the species in simulated gastric fluid (SGF) medium conditions was performed.Results: When the SBF medium conditions were compared, it was determined that the highest Ca absorption of all Salvia species occurred in the SGF conditions. Thus, it can be said that the Ca in plants and foods occurs in the gastric fluid medium and its absorption occurs there. When the result of the correlation analysis was evaluated, it was determined that there was a stronger correlation between the SGF and simulated intestinal fluid (SIF) mediums compared to other mediums.Conclusion: The Ca absorption was determined according to what remained in the SGF the most. Based on the results ob-tained from SBF medium conditions, it can be said which element is taken in which body fluid medium. Information on the differences between samples belonging to different SBF medium conditions was not obtained. However, when the simulated fluid medium conditions were evaluated individually, information was obtained for two or more samples.
Quantitative determination and removal of pesticide residues in fresh vegetables and fruit products by LC-MS/MS and GC-MS/MS
(SpringerLink, 2023) Elmastas, Ayhan; Umaz, Adil; Pirinc, Vedat; Aydin, Firat
Pesticides are the potent agrochemicals used to successfully manage, repel, or stop pests and weeds in agricultural production. This study analyzed 222 pesticide active substances in 90 samples of seven different vegetables and fruits acquired from producers through liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) and gas chromatography-mass spectrometry/mass spectrometry (GC-MS/MS) technology. The validation parameters of each pesticide's active substances were determined. The LOD, LOQ values, and recovery studies of the 222 active substances were 3.00, 10.00 ng/g, and between 76.07 and 108.08%, respectively. The correlation coefficients and measurement uncertainty were determined to be between 0.990-0.999 and 8.91-31.46%, respectively. There were active substances of chlorpyrifos, acetamiprid, azoxystrobin, difenoconazole, malathion, dieldrin, boscalid, triticonazole, tebuconazole, triadimenol, trifloxystrobin, pirimicarb, and dodine among the vegetable and fruit samples used in the study. There were no active substances in 55 (61%) samples. Among the 35 samples (39%), 31 samples (34%) contained only one active substance, whereas four (5%) contained two active substances. However, the amount of active substances in six (7%) samples was above the maximum residue levels (MRL) limits. Various processes used in the study revealed that peeling was the most effective pesticide residue removal strategy. The washing procedure also proved that it reduced some pesticide residues but failed to eliminate all pesticides. The peeling process successfully reduced a significant amount of the active substances from the products, however, residues remained. Washing the fruits with hot water was also effective in removing residues. As a result, analyses of the peeled sections yielded higher pesticide residue concentrations than those of the entire product.