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Öğe The adsorption behavior of crystal violet in functionalized sporopollenin-mediated column arrangements(ACADEMIC PRESS INC ELSEVIER SCIENCE, 2006) Gezici, Orhan; Kucukosmanoglu, Muhittin; Ayar, AhmetThe adsorption behavior of Crystal Violet (CV) on a sporopollenin-based solid phase, carboxylated diaminoethane sporopollenin (CDAE-S), was investigated under column conditions, and the obtained breakthrough profiles were used in evaluations and quantifications. The adsorption capacity of the CDAE-S was observed to be considerably higher than that of diaminoethane sporopollenin (DAE-S), revealing the importance of electrostatic interactions and carboxyl groups in the adsorption of CV on the CDAE-S. The binding of CV on the DAE-S was found to be a typical nonspecific adsorption, whilst cation-exchange was proposed as the main mechanism for monolayer adsorption of CV on the CDAE-S. Hence in the present study, the cation-exchange is suggested as an effective process for removal and recovery of CV from aqueous effluents, and in view of the pH point of zero charge matter, multifunctionality of the CDAE-S is discussed in detail, and various application possibilities based on "aminocarboxylic acid" functionality are also drawn. (c) 2006 Elsevier Inc. All rights reserved.Öğe The adsorption behaviors of Methylene Blue and Methyl Orange in a diaminoethane sporopollenin-mediated column system(ELSEVIER SCIENCE BV, 2006) Kucukosmanoglu, Muhittin; Gezici, Orhan; Ayar, AhmetThe adsorption behaviors of Methylene Blue and Methyl Orange on a diaminoethane sporopollenin (DAE-S) solid phase were investigated in a column arrangement, and breakthrough profiles were used in evaluations and quantifications. The adsorption behaviors were evaluated using some common adsorption isotherm models and Scatchard plot analysis. The results showed that the DAE-S was useful for abstracting anionic dyes from cationic dyes. Thus, the usability of a biopolymer derived material (DAE-S) as a cheap, environmentally friendly and effective solid/stationary phase is discussed through the present study, and the adaptability of the DAE-S to common processes performed under column conditions is also drawn in detail. (c) 2006 Elsevier B.V. All rights reserved.Öğe Adsorptive removal of Methylene blue and Methyl orange from aqueous media by carboxylated diaminoethane sporopollenin: On the usability of an aminocarboxilic acid functionality-bearing solid-stationary phase in column techniques(ELSEVIER SCIENCE BV, 2007) Ayar, Ahmet; Gezici, Orhan; Kucukosmanoglu, MuhittinThe adsorption phenomena of Methylene blue (MB) and Methyl orange (MO) on a carboxylated diaminoethane sporopollenin (CDAE-S) solid phase were investigated in a column arrangement by using breakthrough technique. The adsorption phenomena were evaluated using some common adsorption isotherm models and Scatchard plot analysis, and obtained results were interpreted for evaluating the usability of CDAE-S for removal, recovery and preconcentration of the studied dyes both at the laboratory and industrial scales. On the basis of Scatchard plot analysis, the interaction types between the CDAE-S and the studied dyes were criticized in terms of affinity phenomena. Thus, the usability of a biomacromolecule-derived material, CDAE-S, as a cheap, environmentally-friendly and effective solid-stationary phase exhibiting both cation-exchange and anion-exchange characteristics at the same time, is discussed through the present study. Besides, from the obtained results, the protonated CDAE-S, which functionally resembles an amino acid structure, are presented as a two-in-one solid- stationary phase, and its adaptability to common processes performed under column conditions is also drawn in detail. (C) 2006 Elsevier B.V. All rights reserved.Öğe Akış enjeksiyon-kromatografik yöntemlerle immobilize hümik asidin sabit faz özelliklerinin incelenmesi(Selçuk Üniversitesi Fen Bilimleri Enstitüsü, 2010-09-24) Gezici, Orhan; Kara, HüseyinBu çalışmada; saflaştırılmış hümik asit (HA), 15-35 µm parçacık ebadına sahip aminopropil silika (APS) destek katısına kimyasal bağ oluşumu temelinde immobilize edilmiş ve bazı nükleosit (Uridin, Timidin, Sitidin, Adenosin ve Guanosin) ve nükleobazlara (Urasil, Timin, Sitosin, Adenin, Guanin) karşı sergilediği sabit faz özellikleri kapsamlı bir şekilde incelenmiştir. Çeşitli yöntemler ve tekniklerle (elemental analiz, FTIR, termogravimetrik analizler, potansiyometrik titrasyonlar, yüzey yük özellikleri, katı-sıvı temas açısı ölçümleri, SEM analizleri ve çözünürlük testleri) karakterize edilen immobilize hümik asit esaslı materyalin (EC-HA-APS) çalışılan şartlarda yüksek fiziksel ve kimyasal dayanım sergilediği görülmüştür. FTIR analizlerinden, HA'nın APS'ye amid bağı yoluyla bağlandığı tespit edilmiş ve 170 mgHA/gAPS'lik immobilizasyon verimi elde edilmiştir. Çözünürlük testlerinden, EC-HA-APS'nin, çalışılan şartlara bağlı olarak, pH=8'e kadar kararlı olduğu görülmüş ve EC-HA-APS ile yürütülen HPLC denemeleri pH?7,5'te gerçekleştirilmiştir. EC-HA-APS'nin çalışılan türlere karşı sergilediği sabit faz özellikleri önce; ters-faz sıvı kromatografisi (RPLC) ve hidrofilik etkileşme kromatografisi (HILIC) şartlarında incelenmiş ve kromatografik davranışların şekillenmesinde rol alan mekanizmalar tartışılmıştır. RPLC ve HILIC modları için 4,6x100 mm ölçülerinde EC-HA-APS ile doldurulmuş bir kromatografik kolon kullanılmıştır. Kolon şartlandırma işlemi, hareketli faz bileşimi, sıcaklık ve akış hızı gibi deneysel parametrelerin kapasite faktörü (k'), seçicilik faktörü (?) ve ayırma gücü (RS) üzerine etkisi detaylı bir şekilde incelenmiştir. RPLC ve HILIC şartlarında yürütülen analizlerden sonra, çalışılan türlerin özellikleri de dikkate alınarak, EC-HA-APS'ye ligand-değiştirme özelliği kazandırılıp ligand-değiştirme kromatografisi (LEC) şartlarında da bazı çalışmalar yapılmıştır. Çalışmalarda; 4,6x150 mm ölçülerinde, EC-HA-APS ile doldurulmuş bir kromatografik kolon kullanılmış ve EC-HA-APS'ye ligand-değiştirici özellik kazandırmak için metal iyonu (Mn+) çözeltilerinin kolona basamaklı bir şekilde yüklendiği bir yöntem izlenmiştir. Böylece; sabit faz, kolon şartlarında, ligand değiştirici bir şekle kolayca dönüştürülebilmiştir. Sabit fazın çalışılan şartlardaki maksimum gözlenen kapasitesinin Cu(II) ve Co(II) için sırasıyla 0,278 ve 0,297 mmolMn+/gEC-HA-APS olduğu tespit edilmiştir. LEC şartlarında; hareketli fazdaki organik çözücü oranı (%0-50), sıcaklık (25-45 oC) ve yüklenen metal iyonu türü (Cu2+ ve Co2+) gibi deneysel parametrelerin k', ? ve RS değerleri üzerindeki etkisi incelenmiştir. Yapısında ?NH2 grubu bulunduran nükleosit ve nükleobazların Cu(II) yüklenmiş sabit fazla daha yüksek düzeyde etkileşmeye girdiği görülmüştür. Organik çözücü oranı, RPLC ve LEC şartlarında (%0-50 aralığında) arttıkça; HILIC şartlarında ise (%70-90 aralığında) azaldıkça, türlerin kolondan daha hızlı bir şekilde elue edildikleri tespit edilmiştir. RPLC, HILIC ve LEC modları için türetilen van't Hoff eğrilerinden alıkonma entalpisinin ekzotermik olduğu ve çalışılan sıcaklık aralığında (25-45 oC) sıcaklığa bağlı olarak mekanizmada bir değişikliğin meydana gelmediği anlaşılmıştır. Kromatografik ayırmaların iyileştirilmesinde, sıcaklığın etkisi kapsamlı bir şekilde incelenmiş ve sıcaklık arttırıldıkça türlerin kolondan daha kolay bir şekilde elue edilebildiği, sıcaklıkta yapılacak uygun ayarlamalar ile istenilen ayırma gücüne erişilebildiği görülmüştür. Ayırmaları optimize edebilmek için; HPLC uygulamalarında sıkça rastlanmayan bir deneysel parametre olan sıcaklık gradyenti bu çalışmada (LEC şartlarında) uygulanmış ve bu şekilde kromatografik ayırmaların önemli oranda iyileştirilebildiği görülmüştür. RPLC-HILIC ve RPLC-LEC modları arasındaki ortogonallik geometrik yaklaşım temelinde değerlendirilmiş olup; RPLC ve HILIC modları arasında %48,5; RPLC ve LEC modları arasında da %17,6'lık bir ortogonalliğin olduğu bulunmuştur. Elde edilen sonuçlar; immobilize hümik asidin farklı HPLC modlarında kullanılabilirliği ile ilişkilendirilmiştir. Çalışılan üç HPLC modunda, türleri hem izokratik hem de gradyent şartlarda yüksek tekrarlanabilirlikle ayırmanın mümkün olduğu görülmüştür. Hareketli fazdaki organik çözücü yüzdesi, akış hızı ve sıcaklıkta uygulanan gradyent programları ile ayırmalar önemli oranda iyileştirilebilmiştir. Türlerin k' değerlerindeki standart sapma düzeyinin ?0,03 olduğu tespit edilmiştir. EC-HA-APS ve APS ile doldurulmuş kolonlar üzerinde çeşitli şartlarda kaydedilen kromatogramlar birbiriyle karşılaştırılmış ve böylece immobilizasyon işleminin önemi vurgulanmıştır. Çalışılan HPLC modlarında, türlerin EC-HA-APS sabit fazı üzerindeki elüsyon verimliliklerini değerlendirmek amacıyla, akış enjeksiyon tekniğiyle kaydedilen pik alanları ile HPLC analizlerinden kaydedilen pik alanları karşılaştırılmıştır. Sonuçlar; her iki teknikle elde edilen pik alanlarının %95 ve üzerinde birbiriyle örtüştüğünü göstermiştir. Böylece; türlerin sabit faza tersinmez bir şekilde tutunduğu ile ilgili herhangi bir bulguya rastlanmamıştır. Çeşitli yöntemler ve tekniklerle karakterize edilen EC-HA-APS'nin; ? Çalışılan şartlarda yüksek fiziksel ve kimyasal kararlılığa sahip olması, ? RPLC, HILIC ve LEC gibi farklı kromatografik modlarda çalışabilme esnekliğini göstermesi, ? RPLC, HILIC ve LEC modları arasında kolayca geçiş imkanı vermesi ? Farklı metal iyonları yüklenmek sûretiyle farklı türlere karşı sergilediği kapasite ve seçiciliğin kolayca değiştirilebilmesi, gibi özellikleri göz önünde bulundurulduğunda, sabit faz olarak üstün özellikler sergilediği görülmüştür. İmmobilize hümik asit esaslı materyalin ?multifonksiyonel sabit faz? karakterinin ilk defa bu kadar kapsamlı bir incelemeye/değerlendirmeye tabi tutulduğu bu çalışmayla, farklı HPLC modlarında (ör. RPLC, HILIC ve LEC) kullanılmaya elverişli, ucuz, verimli ve çevreyle dost bir sabit fazı bilim dünyasına sunabilme fırsatı doğmuştur.Öğe Humic-makeup approach for simultaneous functionalization of polyacrylonitrile nanofibers during electrospinning process, and dye adsorption study(TAYLOR & FRANCIS INC, 2016) Gezici, Orhan; Guven, Idris; Ozcan, Fatih; Ertul, Seref; Bayrakci, MevlutA useful methodology is represented to functionalize polyacrylonitrile nanofibers by using humic acid as a makeup agent in electrospinning process. Both morphology and surface chemistry of polyacrylonitrile nanofiber mats were understood to be influenced by incorporation of humic acid into the structure. Physicochemical changes were evidenced by Fourier transform infrared spectroscopy, scanning electron microscope, and surface charge measurements. Unlike some anionic dyes (i.e., methyl orange, methyl red, and Congo red), there was an enhancement in crystal violet (a cationic dye) adsorption after incorporation of humic acid. The Langmuir model fitted well to crystal violet data, and monolayer adsorption capacity was calculated as 81.6 mg/g (r(2) = 0.998).Öğe Investigating sorption characteristics of copper ions onto insolubilized humic acid by using a continuously monitored solid phase extraction technique(ELSEVIER SCIENCE BV, 2007) Gezici, Orhan; Kara, Huseyin; Yanik, Sema; Ayyildiz, H. Filiz; Kucukkolbasi, SemahatThe sorption characteristics of Cu(II) in an insolubilized humic acid (IHA) mediated column system were investigated at various experimental conditions using a solid phase extraction (SPE) technique. Sodium form of the IHA (INaA) was used as solid phase and sorption behaviors were evaluated by using common adsorption isotherms as well as Scatchard plot analysis. Regeneration, loading, washing and stripping steps of SPE were carried out consecutively, and their progresses were monitored through breakthrough curves obtained from a continuous flow-through cell adapted UV-vis spectrophotometer. So, the breakthrough curves were used to visualize distribution of Cu(II) concentration between mobile phase and solid phase, and amount of the Cu(II) sorbed by INaA was obtained from AAS analysis of effluents collected during the stripping steps of particular run. Thus, from the obtained results, the sorption characteristics and usability of IHA as a solid phase for SPE of metal ions was evaluated in detail. (c) 2007 Elsevier B.V. All rights reserved.Öğe Novel humic acid-bonded magnetite nanoparticles for protein immobilization(ELSEVIER SCIENCE BV, 2014) Bayrakci, Mevlut; Gezici, Orhan; Bas, San Zeki; Ozmen, Mustafa; Maltas, EsraThe present paper is the first report that introduces (i) a useful methodology for chemical immobilization of humic acid (HA) to aminopropyltriethoxysilane-functionalized magnetite iron oxide nanoparticles (APS-MNPs) and (ii) human serum albumin (HSA) binding to the obtained material (HA-APS-MNPs). The newly prepared magnetite nanoparticle was characterized by using Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and elemental analysis. Results indicated that surface modification of the bare magnetite nanoparticles (MNPs) with aminopropyltriethoxysilane (APS) and HA was successfully performed. The protein binding studies that were evaluated in batch mode exhibited that HA-APS-MNPs could be efficiently used as a substrate for the binding of HSA from aqueous solutions. Usually, recovery values higher than 90% were found to be feasible by HA-APS-MNPs, while that value was around 2% and 70% in the cases of MNPs and APS-MNPs, respectively. Hence, the capacity of MNPs was found to be significantly improved by immobilization of HA. Furthermore, thermal degradation of HA-APS-MNPs and HSA bonded HA-APS-MNPs was evaluated in terms of the Horowitz-Metzger equation in order to determine kinetic parameters for thermal decomposition. Activation energies calculated for HA-APS-MNPs (20.74 kJ mol(-1)) and HSA bonded HA-APS-MNPs (33.42 kJ mol(-1)) implied chemical immobilization of HA to APS-MNPs, and tight interactions between HA and HA-APS-MNPs. (C) 2014 Elsevier B.V. All rights reserved.Öğe On the removal of some phenolic compounds from aqueous solutions by using a sporopollenin-based ligand-exchange fixed bed - Isotherm analysis(ELSEVIER SCIENCE BV, 2008) Ayar, Ahmet; Gursal, Selpic; Gurten, A. Ali; Gezici, OrhanSingle component adsorption of phenol and 2-, 3- and 4-nitrophenol from water was studied under dynamic column conditions by using a carboxymethyl diaminoethane sporopollenin in a cobalt ion-loaded form, Co(II)-CDAE-S, as solid phase. Adsorption isotherm data were acquired by frontal analysis for five plateau concentrations ranged from 1.25 x 10(-5) to 2.00x 10(-4) mol l(-1). The studied ligand-exchange sporopollenin resin showed a selective adsorptive nature within the group of studied nitrophenols, and the nature of phenols' adsorption on the Co(II)-CDAE-S was analyzed in terms of specific bindings by using Scatchard plot analysis. In light of the Scatchard plot analysis, the adsorption of examined compounds was mainly attributed to the specific bindings based on the ligand-exchange matrix of the studied adsorbent. The nitro-substituted phenols were found to be less strongly adsorbed than the phenol, and both binding strength and theoretical saturation capacity had an obvious relationship with the position of nitro substituent: The theoretical saturation capacities calculated from applied isotherm models exhibited an increase in the order of phenol < 4-nitrophenol < 3-nitrophenol < 2-nitrophenol, whereas a reverse order was showed for binding strengths.Öğe The Sorption Behavior of A Nickel-Insolubilized Humic Acid System in A Column Arrangement(ACADEMIC PRESS INC ELSEVIER SCIENCE, 2005) Gezici, Orhan; Kara, Hüseyin; Ersöz, Mustafa; Abalı, YükselThe sorption characteristics of insolttbilized humic acid (IHA) were investigated for Ni (II) in a column arrangement. The sodium form of the IHA (INaA) was used as a solid phase. Column operations were performed with five steps and all of them were monitored continuously by a flowthrough cell-adapted UV-Vis spectrophotometer. Thus, all solid-phase extraction (SPE) steps were visualized by breakthrough curves and analyses progress were evaluated. However, all calculations and evaluations were focused on the atomic absorption spectrophotometric (AAS) analyses of the solutions collected during the stripping steps. There was a high correlation (r(2), 0.972) between peak area and AAS data of stripping steps. The effect of concentration and pH of the loading solution onto sorption of Ni (II) by INaA was investigated. Sorption characteristics were evaluated by using Freundlich, Langmuir, and Dubinin-Radushkevich (D-R) adsorption isotherms, as well as by Scatchard plot analysis. Multilayer sorption was found to be agreeable for Ni (II). From the D-R isotherm the mean free energy of sorption (E) was calculated (6.65 kJ mol(-1)) and attributed to the multilayer sorption. Finally, the sorption characteristic of the INaA-Ni (II) system was compared with that of the INaA-Cu (II) system, and possible separation of two ions in a binary mixture system is discussed. (c) 2005 Elsevier Inc. All rights reserved.Öğe Sorption behavior of Cu(II) ions on insolubilized humic acid under acidic conditions: An application of Scatchard plot analysis in evaluating the pH dependence of specific and nonspecific bindings(ELSEVIER SCIENCE BV, 2007) Gezici, Orhan; Kara, Huseyin; Ayar, Ahmet; Topkafa, MustafaSorption behavior of Cu(II) ions on a humic acid-based solid phase, insolubilized humic acid (IHA), were investigated under continuous column conditions. The quantitative data were derived on the basis of breakthrough curves obtained at different experimental conditions. For the studied experimental conditions, the highest and lowest observable capacities of IHA toward Cu(II) were found as 48.34 and 0.84 mu mol g(-1), respectively. In order to evaluate the pH dependence of Cu(II) binding on IHA, the effect of influent concentration was investigated at three different pH values (1.0, 2.0 and 3.0), and adsorption isotherms were derived for each acidic condition. The characteristics of Cu(II) bindings were evaluated by using Scatchard plot analysis, and it was observed that under strongly acidic condition, pH 1.0, nonspecific and/or multi-type interactions between Cu(II) and MA were the prevailing effects causing the Cu(II) sorption. On the other hand, at pH 2.0 and 3.0, the role of specific interactions was more clearly observed, and so at pH(s) 2.0 and 3.0, the binding of Cu(II) on IHA was mainly attributed to specific interactions rather than nonspecific ones. For pH 2.0 and 3.0, the binding types of Cu(II) on IHA were sub-classified according to different affinities observed between Cu(II) and IHA, and thus two main types of specific bindings were proposed for the studied influent concentration range (1.0 x 10(-3) to 1.0 X 10(-1) mol l(-1)): Type-1, high-affinity/low capacity and Type-2, low-affinity/high capacity bindings. Finally, probable benefit of each specific binding type in separation of Cu(II) from acidic aqueous media has been discussed in detail. (c) 2006 Elsevier B.V. All rights reserved.Öğe Stepwise Frontal Analysis to Derive Equilibrium Sorption Data for Copper and Aniline on Functionalized Sporopollenin(WILEY-BLACKWELL, 2009) Gezici, Orhan; Ayar, AhmetA dynamic method called stepwise frontal analysis (SFA) was Used to derive equilibrium sorption data of copper and aniline on a carboxylated diaminoethane sporopollenin (CDAE-S) solid phase. The derived data wits modeled on the basis of some common adsorption isotherms, and the importance of Scatchard plot analysis in isotherm modeling was emphasized. In light of the applied isotherm models, the role of aminocarboxylic acid functionalities in the sorption of each chemical species was discussed in terms of specific and nonspecific binding.Öğe Towards multimodal HPLC separations on humic acid-bonded aminopropyl silica: RPLC and HILIC behavior(ELSEVIER SCIENCE BV, 2011) Gezici, Orhan; Kara, HuseyinThe stationary phase characteristics of the material obtained through immobilization of humic acid (HA) to aminopropyl silica (APS) via amide-bond formation were investigated. The material was characterized in terms of elemental analysis, FTIR, thermogravimetric analyses, pH point of zero charge measurements, potentiometric titrations, and contact angle measurements. Amount of HA bonded to APS was determined from the elemental analysis results, and found as 170 mgHA/gAPS. Stability of the material was studied in aqueous media at different pH values, and amount of HA released at pH = 8 did not exceed 2% of the total immobilized HA. Stationary phase characteristics of the well-characterized material were investigated in an HPLC system by using some low-molecular weight polar compounds (i.e. some nucleosides and nucleobases) as test solutes. Effect of some experimental variables such as column conditioning, composition of mobile phase, and temperature on the chromatographic behavior of the studied compounds was studied. Role of ammonium solutions at different pH values on retentive properties of the species was also studied. Retention factors (k') versus volume percentage of organic modifier exhibited a U-curve, which was evaluated as an indication for RPLC/HILIC mixed-mode behavior of the stationary phase. Orthogonality between RPLC and HILIC modes was analyzed through geometric approach, and found as 48.5%. Base-line separation for the studied groups of compounds was achieved under each studied mode, and some differentiations were observed in elution order of the compounds depending on the HPLC mode applied. Chromatograms recorded under RPLC and HILIC modes were compared with those recorded on APS under similar conditions, and thus the influence/importance of HA immobilization process was evaluated in detail. In light of the obtained results, immobilized HA is represented as a useful stationary phase for HPLC separations. (C) 2011 Elsevier B.V. All rights reserved.Öğe Towards multimodal HPLC separations on humic acid-bonded aminopropyl silica: RPLC and LEC behavior(ELSEVIER, 2011) Gezici, Orhan; Kara, HuseyinIn the present study, metal binding property of humic acid (HA) was successfully adapted to the ligand-exchange concept, and metal-loaded immobilized humic acid was used as a ligand exchanger stationary phase for separation of some nucleosides. Humic-acid bonded aminopropyl silica (EC-HA-APS) was turned into ligand exchanger forms by loading aqueous solutions of Cu2+, and Co2+ to the column (4.6 X 150; as mm) packed with EC-HA-APS. Metal ion solutions were loaded to the column in a step-wise manner where the concentration of metal ion solution being loaded to the column was increased gradually between 5 and 100 mM. The progress of metal loading process was monitored via the breakthrough curves propagated stepwise. Ligand-exchange chromatography (LEC) studies were performed on an HPLC system, and chromatographic behaviors of the studied nucleosides (i.e. uridine, Urd; thymidine, Tyd; cytidine, Cyd; adenosine, Ado; and guanosine, Guo) were investigated on Cu2+ and Co2+ loaded forms of the EC-HA-APS (Cu-EC-HA-APS and Co-EC-HA-APS). Effect of mobile phase composition, temperature, and the type of metal ion loaded to the column on the retentive behaviors of the compounds was studied, in detail. The studied solutes exhibited mixed-mode RPLC/LEC behavior on the stationary phase. Metal-loaded column (M-EC-HA-APS) was easily regenerated into its original form. EC-HA-APS, with 98 +/- 2% metal recoveries, by using aqueous mixture of EDTA + NH3 at pH = 7.5. Thus, the stationary phase exhibited a high flexibility between RPLC and LEC modes. This property, also, made it possible to convert the stationary phase into various ligand exchanger forms by loading different metal ions. Hence, capacity and selectivity of the stationary phase towards the studied species was manipulated easily by loading different metal ions to the stationary phase. Baseline separation for the studied species was achieved on Cu-EC-HA-APS and Co-EC-HA-APS and some differentiations were observed in capacity and selectivity, depending on the type of metal loaded. Thus, being as the first endeavor on usability of immobilized HA as a ligand exchanger stationary phase, the present study is believed to be useful to understand multifunctional character of HA-based solid/stationary phases. (C) 2011 Elsevier B.V. All rights reserved.
