Wadhwa, Sham Kumar | Tüzen, Mustafa | Kazi, Tasneem Gul | Soylak, Mustafa | Hazer, Baki

Article | 2014 | Food Chemistry152 , pp.75 - 80

A new adsorbent, polyhydroxybutyrate-b-polyethyleneglycol, was used for the separation and preconcentration of copper(II) and lead(II) ions prior to their flame atomic absorption spectrometric detections. The influences of parameters such as pH, amount of adsorbent, flow rates and sample volumes were investigated. The polymer does not interact with alkaline, alkaline-earth metals and transition metals. The enrichment factor was 50. The detection limits were 0.32 µg L-1 and 1.82 µg L-1 for copper and lead, respectively. The recovery values were found >95%. The relative standard deviations were found to be less than 6%. The validat . . .ion of the procedure was performed by analysing certified reference materials; NIST SRM 1515 Apple leaves, IAEA-336 Lichen and GBW-07605 Tea. The method was successfully applied for the analysis of analytes in water and food samples. © 2013 Elsevier Ltd. All rights reserved Daha fazlası Daha az

Tüzen, Mustafa | Şahiner, Samet | Hazer, Baki

Article | 2016 | Food Chemistry210 , pp.115 - 120

A new biodegradable polyhydroxybutyrate diethanol amine (PHB-DEA) polymer was used as adsorbent for the sensitive and selective separation, preconcentration and determination of Pb(II), Cd(II) and Zn(II) by using atomic absorption spectrometry. Diethyl dithiocarbamate was used as chelating reagent. Analytical parameters such as pH, eluent type and its volume, flow rates of sample solution, ligand amount, sample volume were optimized. Effects of some cations, anions and transition metal ions were also investigated. Enrichment factor and relative standard deviation were found to be 100 and 3%, respectively. The limits of detection bas . . .ed on three times standard deviation of blanks (N = 21) were found 1.05 µg L-1 for Pb(II), 0.42 µg L-1 for Cd(II) and 0.13 µg L-1 for Zn(II). Limits of quantification (10 s, N = 21) were found 3.47 µg L-1 for Pb(II), 1.39 µg L-1 for Cd(II) and 0.43 µg L-1 for Zn(II). Accuracy evaluation of the method was confirmed with analyses of certified reference materials (NIST SRM 1515 Apple leaves, IAEA 336 Lichen, GBW 07605 Tea). Optimized method was applied to tap water and food samples after microwave digestion method. Cadmium and lead values in some samples were found higher than legal limits. © 2016 Elsevier Ltd. All rights reserved Daha fazlası Daha az

Açıkkapı, Ayşe Nihan | Tüzen, Mustafa | Hazer, Baki

Article | 2019 | Food Chemistry284 , pp.1 - 7

A newly synthesized polystyrene-g-polyoleic acid-g-polyethylene glycol graft copolymer (PoleS-PEG) was used as adsorbent in the solid phase microextraction of selenium ions by using electrothermal atomic absorption spectrometry (ETAAS). Neodymium magnet was used for separation of analyte ions. Various analytical parameters such as pH, adsorbent amount, mixing time, eluent solution, sample volume, etc. were optimized. The matrix effects of some cations and anions were also studied. The capacity of the adsorbent was found 11.5 mg g -1 . The preconcentration factor was found to be 50. The detection limit (LOD) and quantification limit . . .(LOQ) were found 6.06 ng L -1 and 20 ng L -1 , respectively. The calibration curve was linear in the range of 0.02–4.0 µg L -1 . Relative standard deviation was found 3.2%. The accuracy of the method was provided by using standard reference materials. The optimized method was successfully applied to natural water and food samples. © 2019 Elsevier Lt Daha fazlası Daha az