Browsing by Author "Gürkan R."
Now showing items 41-60 of 69
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A micellar sensitized kinetic method for quantification of low levels of bisphenol A in foodstuffs by spectrophotometry
Temel N.K.; Gürkan R. (Royal Society of Chemistry, 2017)In the current study, because of its potential to leach out into foodstuffs as a result of food contact uses, a new kinetic method for the monitoring and determination of bisphenol A in foods by spectrophotometry for a ... -
Micelle-Mediated Extraction and Flame Atomic Absorption Spectrometric Method for Determination of Trace Cobalt Ions in Beverage Samples
Ulusoy H.I.; Gürkan R.; Demir O.; Ulusoy S. (2012)A new method has been developed for preconcentration of cobalt at trace levels in beverage samples using calcon carboxylic acid as chelating agent and cetyl pyridinium chloride as an auxiliary ligand and entrapped into ... -
Natural deep eutectic solvent-based ultrasound-assisted-microextraction for extraction, pre-concentration and analysis of methylmercury and total mercury in fish and environmental waters by spectrophotometry
Altunay N.; Elik A.; Gürkan R. (Taylor and Francis Ltd., 2019)In this study, a simple, pH-controlled, and natural deep eutectic solvent-based microextraction (NADES-ME) procedure is proposed before the spectrophotometric analysis of methylmercury (MeHg) and total mercury in fish and ... -
A new cloud point extraction procedure for determination of inorganic antimony species in beverages and biological samples by flame atomic absorption spectrometry
Altunay N.; Gürkan R. (2015)A new cloud-point extraction (CPE) for the determination of antimony species in biological and beverages samples has been established with flame atomic absorption spectrometry (FAAS). The method is based on the fact that ... -
A new micellar mediated cloud-point extraction procedure for sensitive and selective determination of trace amounts of total iodine in Milk-based nutritional products by means of indirect spectrophotometry
Altunay N.; Gürkan R. (2015)A new micellar mediated cloud-point extraction procedure (CPE) has been developed for sensitive and selective determination of trace amounts of total iodine by means of indirect spectrophotometry. The method is based on ... -
A new preconcentration procedure to quantify total acid hydrolyzed fluoride in selected beverages and foods by spectrophotometry
Gürkan R.; Altunay N.; Korkmaz S. (2015)A new micellar-mediated, cloud-point extraction (CPE) method has been developed for the quantification of trace levels of fluoride by means of spectrophotometry. The method is based on the selective ion association of ... -
A new simple UV-Vis spectrophotometric method for determination of sulfite species in vegetables and dried fruits using a preconcentration process
Altunay N.; Gürkan R. (2016)A new eco-friendly, selective and sensitive method was developed for preconcentration and determination of trace levels of sulfite by ultrasonic-assisted cloud point extraction (UA-CPE). The method is based on the selective ... -
A novel indicator system for catalytic spectrophotometric determination and speciation of inorganic selenium species (Se(IV), Se(VI)) at trace levels in natural lake and river water samples
Gürkan R.; Ulusoy H.I.; Akçay M.; Bulut P. (2011)A novel catalytic kinetic method is proposed for the determination of Se(IV), Se(VI), and total inorganic selenium in water based on the catalytic effect of Se(IV) on the reduction of Celestine blue by sodium sulfide at ... -
A Novel Preconcentration Procedure Using Neutral Red as Ion-Pairing Reagent for Determination of Inorganic Dissolved Arsenic Species in Different Water and Beverages by Spectrophotometry
Gürkan R.; Kir U.; Altunay N. (2015)In the current study, a new cloud point extraction (CPE) procedure was developed for the separation and preconcentration of inorganic soluble As species, As(III), As(V), and total As in water and beverage samples. Selective ... -
Photocatalytic degradation of a textile azo dye, Sirius Gelb GC on TiO 2 or Ag-TiO 2 particles in the absence and presence of UV irradiation: The effects of some inorganic anions on the photocatalysis
Özkan A.; Özkan M.H.; Gürkan R.; Akçay M.; Sökmen M. (2004)The aqueous phase photocatalytic degradation of Sirius Gelb GC used in the textile industry, was investigated. In order to optimize the working pH, three different dye solutions were prepared at pH 3.5; 7.0 and 11.0. One ... -
Preconcentration and determination of trace nickel and cobalt in milk-based samples by ultrasound-assisted cloud point extraction coupled with flame atomic absorption spectrometry
Temel N.K.; Sertakan K.; Gürkan R. (Humana Press Inc., 2018)In this study, ultrasound-assisted cloud point extraction (UA-CPE) method was developed for the determination of Ni(II) and Co(II) in milk-based products. After extraction and preconcentration, the Ni(II) and Co(II) contents ... -
Preconcentration and determination of trace vanadium(V) in beverages by combination of ultrasound assisted-cloud point extraction with spectrophotometry
Temel N.K.; Gürkan R. (Slovensko Kemijsko Drustvo, 2018)A novel ultrasound assisted-cloud point extraction method was developed for preconcentration and determination of V(V) in beverage samples. After complexation by pyrogallol in presence of safranin T at pH 6.0, V(V) ions ... -
Preconcentration and determination of vanadium and molybdenum in milk, vegetables and foodstuffs by ultrasonic-thermostatic-assisted cloud point extraction coupled to flame atomic absorption spectrometry
Gürkan R.; Korkmaz S.; Altunay N. (2016)A new ultrasonic-thermostatic-assisted cloud point extraction procedure (UTA-CPE) was developed for preconcentration at the trace levels of vanadium (V) and molybdenum (Mo) in milk, vegetables and foodstuffs prior to ... -
Preconcentration and indirect quantification of trace nitrite, nitrate and total nitrite in selected beverage and milk samples using ion-pairing cloud-point extraction with acridine orange
Gürkan R.; Altunay N. (Academic Press Inc., 2018)A new indirect preconcentration method was developed for micellar-sensitive detection of trace nitrite as analyte by spectrophotometry. It is based on selective ion-pairing complex formation of triiodide ion, I3 ? with ... -
A preconcentration method for indirect determination of acrylamide from chips, crackers and cereal-based baby foods using flame atomic absorption spectrometry
Altunay N.; Gürkan R.; Orhan U. (2016)Acrylamide is a toxic species for human health, and is a Maillard reaction product which forms spontaneously in heat treatment process of foods. Therefore, a simple, fast and cost-effective method was developed for the ... -
Quantification of 5-hydroxymethylfurfural in honey samples and acidic beverages using spectrophotometry coupled with ultrasonic-assisted cloud point extraction
Gürkan R.; Altunay N. (2015)The simple, cost-effective and fast preconcentration method using ultrasonic-assisted cloud point extraction (UA-CPE) has been developed for determination of 5-hydroxymethylfurfural (5-HMF) by means of spectrophotometry. ... -
A reliable determination of zinc levels in beverages with and without alcohol by flame atomic absorption spectrometry after cloud point extraction
Gürkan R.; Altunay N. (2013)Cloud point extraction (CPE) has been used for the preconcentration and quantification of zinc after the formation of a stable complex with N-phenylbenzohydroxamic acid (PBHA) at pH 9.0 and analysis by flame atomic absorption ... -
A reliable method of quantification of trace copper in beverages with and without alcohol by spectrophotometry after cloud point extraction
Gürkan R.; Altunay N. (2013)A new cloud point extraction (CPE) method was developed for the separation and preconcentration of copper (II) prior to spectrophotometric analysis. For this purpose, 1-(2,4-dimethylphenyl) azonapthalen-2-ol (Sudan II) was ... -
Removal of Cu(II), Zn(II) and Co(II) ions from aqueous solutions by adsorption onto natural bentonite
Kubilay Ş.; Gürkan R.; Savran A.; Şahan T. (2007)In this study, the removal of Cu(II), Zn(II) and Co(II) ions from aqueous solutions using the adsorption process onto natural bentonite has been investigated as a function of initial metal concentration, pH and temperature. ... -
Removal of some heavy metal cations from aqueous solution by adsorption onto natural kaolin
Ceylan H.; Şahan T.; Gürkan R.; Kubilay Ş. (2005)The adsorption removal of some heavy metal cations such as Cu(II), Zn(II) and Co(II) from aqueous solution onto kaolin has been studied using the batch method with initial metal ion concentrations within the range 15-70 ...