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Determination of gentamicin by using square wave anodic stripping voltammetry with poly (?-cyclodextrin-p-toluene sulfonic acid) modified glassy carbon electrode
(Springer, 2024) Burc, Muammer; Titretir Duran, Serap; Gungor, Oznur; Karagozler, Ali Ersin
In this study, an effective electrochemical method based on modified glassy carbon electrode was developed for the determination of gentamicin. Firstly, the poly beta-cyclodextrin-p-toluene sulfonic acid/glassy carbon electrode as gentamicin selective electrode was prepared by electropolymerization technique. In situ electropolymerization of beta-cyclodextrin and p-toluene sulfonic acid was conducted on bare glassy carbon electrode by controlled potential cycling. Characterization of the prepared poly beta-cyclodextrin-p-toluene sulfonic acid/glassy carbon electrode was performed using cyclic voltammetry and electrochemical impedance spectroscopy. Then, the effects of various parameters were investigated using square wave anodic stripping voltammetry in citrate buffer containing 4.0 mmol L-1 gentamicin. The calibration graph plotted over the range of 0.06-4.0 mmol L-1 gentamicin concentration showed high linearity. Correlation coefficient, detection limit and quantitation limit were obtained from the calibration graph as 0.9999, 3.7 mu mol L-1 and 12.4 mu mol L-1, respectively. According to these results, it is seen that the prepared poly beta-cyclodextrin-p-toluene sulfonic acid/glassy carbon electrode can be successfully used for the determination of gentamicin in many pharmacological, medical and biochemical applications.
DETERMINATION OF NAPROXEN BY USING DIFFERENTIAL PULSE VOLTAMMETRY WITH POLY(ANILINE-2-SULFONIC ACID) MODIFIED BORON DOPED DIAMOND ELECTRODE
(Soc Chemists Technologists Madeconia, 2022) Gungor, Oznur
In this study, an electrochemical sensor based on a boron doped diamond electrode (BDDE) was developed for the determination of naproxen (NAP) using a poly(aniline-2-sulfonic acid)/boron doped diamond electrode, p(A2SA/BDDE). Polymerization of A2SA was conducted in a water/acetonitrile (1:1) mixture containing 0.1 M sodium perchlorate (NaClO4) on bare BDDE and the electrochemical properties studied by cyclic voltammetry in ferricyanide/KNO3 solution. The prepared p(A2SA/BDDE) was used for detection of NAP. Effects of parameters such as monomer type and concentration, the number of cycles, and scan rate were investigated using differential pulse voltammetry (DPV) in phosphate buffer containing 0.75 mM NAP. The effect of electrolyte type and pH on DPV responses to NAP were also studied. The oxidative current peak stem from NAP concentration observed at 1.1 V potential. A linear calibration curve was obtained in the range of 0.05-1.00 mM NAP concentration. Correlation coefficient (R-2), detection limit, and quantification limit were calculated as 0.9944, 0.0328 mM, and 0.1093 mM, respectively. In conclusion, it may be claimed that the modified electrode constructed in this work can be used successfully as a naproxenselective membrane due to its ease of preparation, high R-2 value, and good reproducibility.
Development of Gum-Arabic-based polyurethane membrane-modified electrodes as voltammetric sensor for the detection of phenylalanine
(Springer, 2021) Alisik, Funda; Burc, Muammer; Titretir Duran, Serap; Gungor, Oznur; Cengiz, Mahmut Alper; Koytepe, Suleyman
In this study, L-phenylalanine (L-Phe) sensors were prepared from Gum-Arabic-based polyurethanes, by the modification of Pt electrode. Firstly, Gum-Arabic-based polyurethanes were synthesized by solution polymerization technique and characterized with Fourier transform infrared spectroscopy, thermogravimetric analysis, differential thermal analysis, scanning electron microscopy and atomic force microscopy techniques. Then, L-Phe selective electrodes were prepared by coating the platinum electrode with different thickness Gum-Arabic-based polyurethane. L-Phe responses of the modified electrodes were investigated by differential pulse voltammetry technique. Sensor parameters such as scanning speed, film thickness, electrolyte type and pH were examined in detailed. Prepared electrodes were showed R-2 = 0.9972 for the concentration range of 200-1000 mu M L-Phe. The limit of detection and the limit of quantification of the prepared L-Phe selective modified electrode were calculated as 48.01 mu M and as 144.02 mu M, respectively. After ten consecutive measurements with the prepared L-Phe selective electrode, 98.8% stable result was obtained between the first and tenth reading and the RSD% value was found to be 1.21% for ten replicates. Consequently, prepared Gum-Arabic-modified sensors can be used successfully for the detection of the L-Phe with large concentration areas, high sensitivity and repeatability. [GRAPHICS] .
Differential Pulse Voltammetric (DPV) Determination of the Local Anesthetic Bupivacaine using Polyimide Membrane-Based Electrodes
(Taylor & Francis Inc, 2020) Gungor, Oznur; Ozcan, Imren; Erdogan, Mehmet Ali; Ates, Burhan; Koytepe, Suleyman
Aromatic selective polyimide (PI) membrane based voltammetric electrodes were prepared for bupivacaine measurements. Polyimide membranes were synthesized from 4,4 '-diaminobenzanilide (DABA) and different aromatic dianhydrides (pyromellitic dianhydride (PMDA), benzophenone-3,3 ',4,4 '-tetracarboxylic dianhydride (BPDA), 4,4 '-oxydiphthalic anhydride (ODPA)) through two-step polycondenzation reactions. The structural properties of the obtained benzanilide based PIs were characterized by various analytical techniques. For the preparation of voltammetric electrodes, these polyimide films were coated with polyimide solution by drop-casting on the surface of a platinum working electrode. Due to the excellent film properties and suitable porosity, the prepared benzanilide based polyimide films were used as the membrane for selective determination of bupivacaine in the presence of interferents that included lactose, glucose and sucrose. For this reason, the selectivity of the modified electrode to bupivacaine obtained from the prepared PI film toward the potential interferences was investigated by differential pulse voltammetry (DPV). The results of voltammetric study showed that polyimide films responded to only bupivacaine at a potential of approximately +0.92 V. The polyimide membrane modified electrode showed a rapid response time, a high R-value of 0.9941, high reproducibility and good selectivity for bupivacaine. The limit of detection (LOD) and the limit of quantitation (LOQ) were determined to be 16.82 mu M and 50.46 mu M, respectively. Thus, benzanilide based polyimides may be successfully used as selective membranes for preparation of bupivacaine sensors. This structure may be a precursor for the preparation of simultaneous or needle-shaped sensors in the future.
Electrochemical determination of ceftriaxone using polyurethane-modified electrode containing caffeic acid and chitosan
(Taylor & Francis Inc, 2022) Hassine, Chedia Ben Ali; Gungor, Oznur; Burc, Muammer; Ozcan, Imren; Koytepe, Suleyman; Duran, Serap Titretir
The aim of this work was to develop an electrochemical sensor based on caffeic acid and chitosan-containing polyurethane (CAC-PU) films modified platinum electrode for ceftriaxone (CFX) determination. For this aim, firstly the CAC-PU structures were synthesized from three different diisocyanates and these structures were characterized with spectroscopic, thermal and surface analysis techniques. Then, these CAC-PU structures were coated on bare Pt electrode surface for the preparation of CFX selective sensors. Throughout this study several analytical parameters, such as film thickness, electrolyte type, pH effect, and scan rate were investigated by using differential pulse voltammetry (DPV) method. Under the optimized conditions, the voltammetric test results showed best analytical performances for CFX detection with a linear range from 0.1 to 1.5 mM. Limit of detection (LOD) and correlation coefficient (R-2) were obtained 52 mu M and 0.9991 using CAC-PU modified electrode, respectively. Stability of the modified electrode was found to be 96.78% by using reproducibility experiments (n = 10). Applicable of the presented sensor was tested in two synthetic urine samples and recoveries values were obtained 98.7% and 110%, respectively. The prepared modified electrode exhibits high repeatability, fast response, and high sensitivity, which makes it suitable for the detection of CFX in urine samples.
Fabrication of electrospun polycaprolactone/chitosan nanofiber-modified screen-printed electrode for highly sensitive detection of diazinon in food analysis
(Elsevier Sci Ltd, 2022) Topsoy, Oguz Kagan; Muhammad, Fakhriy; Kolak, Seda; Ulu, Ahmet; Gungor, Oznur; Simsek, Murat; Koytepe, Suleyman
In the present study, a screen-printed electrode for Diazinon (DZN) detection was modified with nanofibers prepared via electrospinning technique. The chemical structure, morphology, and crystallinity of the nanofibers were characterized in detail. The electrochemical behaviors of the modified screen-printed electrode were evaluated by cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy. The spinning time, pH value and scan rates were optimized at 6 min, 5.25, and 50 mVs(-1), respectively. The limit of detection as 2.888 nM was obtained over a linear concentration range (3 nM-100 nM). Besides, DZN selectivity, repeatability, and storage stabilities of the developed sensor were proven. Meanwhile, the sensor was successfully applied for the determination of DZN in the tomato juice sample with recovery values in the range of 93.27-108.30%. The developed sensor could be a promising candidate to detect the presence and level of DZN in real samples.
Fructose-Based Polyurethane Membranes: Synthesis, Characterization, and Their Use as Voltammetric pH Electrode
(Taylor & Francis As, 2015) Gungor, Oznur; Pasahan, Aziz; Cengiz, Mahmut Alper; Koytepe, Suleyman; Seckin, Turgay
In this study, polyurethane films prepared from the 4,4-diphenylmethane diisocyanate (MDI), ethylene glycol, and different ratio fructose were used to prepare a novel amperometric pH electrode. Fructose-based films were characterized by FT-IR, DSC, DTA, and TGA. Prepared polyurethanes exhibited suitable T-g(degrees C), good thermal stability and good adhesive properties. The incorporation of saccharides into the PU structure results in a higher crosslinking density and a higher content of hard segments. Furthermore, the behavior of films prepared from polyurethane solutions containing 1%, 3%, 5%, and 10% fructose toward pH changes were examined by normal pulse voltammograms technique and diferantial pulse voltammetry. [GRAPHICS] .
High Sensitive Voltammetric Gentamicin Sensor using Poly (3-thiophenecarboxylic acid-co-3-methylthiophene) Modified Glassy Carbon Electrode
(Wiley-V C H Verlag Gmbh, 2022) Burc, Muammer; Duran, Serap Titretir; Gungor, Oznur; Koytepe, Suleyman
For the determination of gentamicin in biomedical applications, sensitive, fast and low cost voltammetric sensor has been developed. Prepared sensor was succecfully used for determination of gentamicine in synthetic urine samples with different voltammetric measurement methods. Firstly, glassy carbon electrode was modified using cyclic voltammetry technique by electropolymerization of 3-thiophenecarboxylic acid and 3-methylthiophene. Then, optimization of the electrochemical parameters was carried out for modifed electrode. With this modified electrode, gentamicin determination was performed in the linear range of 0.05-4.00 mM. The correlation coefficient, limit of detection and limit of quantitation were calculated as 0.9999, 0.039 mM and 0.129 mM, respectively.
High-sensitivity electrochemical sensor using no nanomaterials for the detection of ciprofloxacin with poly 2-(hydroxymethyl)thiophene-modified glassy carbon electrode
(Springer, 2024) Burc, Muammer; Gungor, Oznur; Duran, Serap Titretir
In this study, a new sensor was developed for the detection of ciprofloxacin that is easy to prepare, selective and has excellent sensitivity through electrochemical polymerization of 2-(hydroxymethyl)thiophene on glassy carbon (GC) electrode. Electrode modifications were performed by using cyclic voltammetry. The morphology and surface properties of the modified electrode were characterized by using scanning electron microscopy. Determination of ciprofloxacin with poly 2-(hydroxymethyl)thiophene-modified GC electrode was performed by square wave voltammetry in 0.1 M citrate buffer (pH 5.00) at 1.1 V. The prepared sensor showed a wide linear range from 0.1 to 200 mu M, detection limit of 7 nM, a limit of quantitation of 22 nM, a correlation coefficient of 0.9993, excellent sensitivity of 99.6% and a relative standard deviation of 0.40%. The sensor was used to determine ciprofloxacin in human urine samples, and a recovery efficiency of 99.24-100.36% was obtained. According to the results in this study, we believe that the sensor developed can be used for the detection of ciprofloxacin in clinical laboratories.
A new voltammetric sensor for penicillin G using poly (3-methylthiophene)-citric acid modified glassy carbon electrode
(Elsevier Science Sa, 2022) Gungor, Oznur; Burc, Muammer; Hassine, Chedia Ben Ali; Koytepe, Suleyman; Duran, Serap Titretir
In this study, an effective voltammetric sensor was developed for determination of penicillin G by electro-polymerization of 3-methylthiophene with citric acid on glassy carbon electrode. Penicillin G selective electrode was prepared in water:acetonitrile (1:1) mixture containing 0.1 M sodium perchlorate as electrolyte medium with cyclic voltammetry. Then, the electrochemical behavior of penicillin G on poly(3-methylthiophene) based membrane modified electrode was investigated by cyclic voltammetry, differential pulse voltammetry and differential pulse stripping voltammetry techniques. When the penicillin G responses of the modified glassy carbon electrode were compared with the bare glassy carbon electrode responses, it was seen that the selectivity and sensitivity of the penicillin G responses of the modified electrode significantly increased. A linear calibration graph for penicillin G was obtained in the concentration range of 0.07 to 4.0 mM with the prepared electrode. The R2 value was calculated as 0.9999 from the linear calibration curve. The limit of detection and limit of quantitation of the poly(3-methylthiophene)-citric acid modified glassy carbon electrode for penicillin G were calculated as 8 mu M and 28 mu M, respectively. In addition, the developed electrode for the detection of PeG was applied to milk samples. The recovery efficiency of the poly(3-methylthiophene)-citric acid modified glassy carbon electrode was obtained in the range of 93 % and 103 % for three different milk samples. As a result; the modified electrode can be used for residue penicillin detection in food and biological samples.
A novel electrochemical biosensor based on polyimide- boron nitride composite membranes
(Taylor & Francis As, 2017) Aksoy, Busra; Pasahan, Aziz; Gungor, Oznur; Koytepe, Suleyman; Seckin, Turgay
Polyimide (PI) and polyimide-boron nitride (PI-BN) composites as dopamine-selective membrane were synthesized. The structures of the monomer, pure PI, and PI-BN composites were characterized by FT-IR, SEM, and thermal analysis techniques. Experiment results showed that introduction of BN particles increased porosity, selectivity and improved heat-resistance of polyimide matrix. Selectivity of PI-BN composite membranes toward dopamine and interferences was examined by DPV technique. Electrochemical measurement results illustrated that polyimide membrane containing 5% BN possessed wide linear ranges, excellent sensitivity, selectivity, reversibility, and low detection limits (4 X 10(-8) M). The polyimide membrane was very high R value (0.9904). [GRAPHICS] .
Preparation and properties of selective polyurethane films and their use for the development of biomedical dopamine sensor
(Taylor & Francis As, 2016) Savan, Ebru Kuyumcu; Pasahan, Aziz; Aksoy, Busra; Gungor, Oznur; Koytepe, Suleyman; Seckin, Turgay
Polyurethane films were synthesized by 3,4-divanillyltetrahydrofuran and different diisocyanates. These prepared polyurethanes were characterized by FT-IR, DSC, DTA, and TGA techniques. For the amperometric applications, synthesized polyurethanes exhibited suitable T-g (degrees C), good thermal stability and good adhesive properties. In addition, because of their interesting film properties, attempts were made to prepare dopamine-sensing electrode. For this reason, selectivity of film-coated electrodes obtained from the chemically prepared polyurethanes toward electroactive and nonelectroactive species were examined by means of DPV technique. From the electrochemical results obtained, it has been demonstrated that the PU-1-coated electrode can be used for the development of biomedical sensor.
PREPARATION OF A POLYURETHANE MEMBRANE TESTOSTERONE SENSOR AND ITS APPLICATION USING SQUARE-WAVE STRIPPING VOLTAMMETRY
(Soc Chemists Technologists Madeconia, 2022) Harman, Cemre Zeynep; Gungor, Oznur
A novel electrochemical sensor for testosterone detection has been prepared by the chemical modification of a gold electrode (AuE). For the electrode modification, specific polyurethane (PU) films were synthesized from hexamethylene diisocyanate, olivetol, polyethylene glycol-100 (PEG100) and beta-cyclodextrin. The synthesized PUs were investigated as selective films, and were used to coat a AuE surface at different concentrations and thicknesses. The testosterone responses of the modified electrodes were investigated by square-wave voltammetry (SWV). One separated cathodic SWV peak was obtained for testosterone at -0.390 V, with the prepared PU-modified AuE in 0.1 M phosphate buffer (PB) (pH 7.2). The linearity of testosterone responses of the prepared PU modified electrode was obtained over a concentration range of 0.1-1.0 mu M (R-2 = 0.995). It was observed that the response of the electrode increased regularly and sensitively with increasing testosterone amount. The detection limit, relative standard deviation and sensitivity of modified electrode were found to be approximately 5.69 nM, 1.669 % and 98.331 %, respectively. The PU-modified AuE exhibited good selectivity and a low response time for testosterone. Therefore, the prepared testosterone sensor offers a good alternative for fast and practical testosterone determination in clinical or biomedical studies.
Preparation of Molecularly Imprinted Metoprolol Sensor from Poly(aniline-co-p-toluene sulfonic acid)
(Univ Tehran, Fac Chemistry, Center Excellence Electrochemistry, 2022) Gungor, Oznur; Hassine, Chedia Ben Ali; Burc, Muammer; Koytepe, Suleyman; Duran, Serap Titretir
In this study, the metoprolol (MTP), which is a beta-blocker class molecule used in hypertension treatment, was determined by modifying the glassy carbon electrode (GCE) with a molecular imprinting technique. Firstly, p-toluene sulfonic acid (PTSA) and aniline (AN) were co-electropolymerized in the presence of MTP as a template molecule on GCE and MTP contained poly(aniline-co-p-toluene sulfonic acid) (p(AN-co-PTSA)) film was obtained. Then, the template metoprolol molecule was desorbed from the conductive p(AN-co-PTSA) film structure on the GCE surface using hydrochloric acid. Obtained molecularly imprinted electrodes were used to determine MTP by the square wave voltammetry (SWV) method. The modified electrodes obtained showed a correlation coefficient (R-2) of 0.9995 in the 40-1500 mu M MTP concentration range. The limit of detection (LOD) and the limit of quantification (LOQ) of the p(AN-co-PTSA) film modified MTP electrodes were 37.9 mu M and 126.3 mu M, respectively. A standard deviation of 1.33% was observed for the first three replicates with the same modified electrode. For the time reproduced electrodes, stable reproducibility was achieved between the first electrode result and the tenth electrode result. For the modified MTP electrode, the relative standard deviation (RSD%) value was calculated to be 2.53%. As result, the molecularly imprinted electrodes prepared with p(AN-co-PTSA) film have low response time, high reproducibility, good stability, and high selectivity for the determination of MTP.
Preparation of Novel Sensors Based on Polyimide Membrane for Sensitive and Selective Determination of Dopamine
(Taylor & Francis Inc, 2016) Aksoy, Busra; Gungor, Oznur; Koytepe, Suleyman; Seckin, Turgay
Polyimides as dopamine selective membrane were prepared from 4,4'-diaminodicyclohexyl-methane and different dianhydrides. The chemical structure and thermal properties of these polyimides were examined. For the voltammetric sensor applications, polyimides exhibited suitable glass transition temperature (T-g), high thermal stability, and good adhesive properties. Moreover, polyimides were coated onto Pt electrode surface for the preparation of dopamine selective electrodes. Electrochemically dopamine responses of polyimide-coated electrodes were examined by differential pulse voltammetry. The sensor characteristics such as sensitivity, linearity, selectivity, response time, and stability of the prepared sensors have been determined. Prepared polyimide-coated electrodes can be used for selective and sensitive dopamine detection.
Synthesis, Characterization of Guar-Containing Polyurethane Films and their Non-enzymatic Caffeic Acid Sensor Applications
(Taylor & Francis Inc, 2017) Duran, Serap Titretir; Pasahan, Aziz; Ayhan, Nurcan; Gungor, Oznur; Cengiz, Mahmut Alper; Koytepe, Suleyman
Stable voltammetric sensors were fabricated by dropping the guar-containing polyurethane films on a platinum electrode for the non-enzymatic determination of caffeic acid. The voltammetric responses of PU-G-1% toward caffeic acid have a linear concentration range from 1 to 15mM with a correlation coefficient of 0.9938. The detection limit of PU-G-1% electrode was approximately 0.25mM. PU-G-1% sensor showed the good sensitivity, selectivity, high R-value, low detection limit, and high reproducibility toward caffeic acid. Therefore, it is claimed that the polyurethane film containing 1% guar can be used as an excellent selective membrane for caffeic acid detection in the presence of interferent molecules. [GRAPHICS] .
Titanium dioxide-multiwalled carbon nanotube/polyimide composite film modified electrodes for simultaneous voltammetric detection of ascorbic acid, uric acid and dopamine as biomarker molecules
(Springer, 2022) Gungor, Oznur; Ozgul, Onur; Aksoy, Busra; Okusluk, Funda; Koytepe, Suleyman
Titanium dioxide-multiwalled carbon nanotube/polyimide (TiO2-MWCNT/PI) composite film modified electrodes for simultaneous detection of dopamine (DA), uric acid (UA), and ascorbic acid (AA) in clinical or biomedical applications were prepared. Firstly, TiO2-MWCNT and polyimide structures were synthesized. Then, TiO2-MWCNT/PI composites containing different ratios of MWCNT were subsequently prepared and characterized with chemical, thermal and morphological analysis techniques. Synthesized TiO2-MWCNT/PI composites were coated on the platinum electrode surface. Prepared electrodes were used to sense DA, UA, and AA with voltammetric measurements. LOD and LOQ parameters of modified electrodes for DA were observed 8.5114 mu M and 25.5342 mu M, respectively. The R-2 value for the DA in the linear range from 175 to 325 mu M was obtained 0.9967 (in the existence of AA and UA). After five repeatability results, 96.3% AA, 98.2% DA, and 88.3% UA peak currents were maintained. The modified electrode exhibited good selectivity, acceptable durability, high repeatability, and sensitivity.
Voltammetric Determination of ?-Lipoic Acid using Poly(Vanillin) Modified Platinum Electrode
(Univ Tehran, Fac Chemistry, Center Excellence Electrochemistry, 2020) Duran, Serap Titretir; Hassine, Chedia Ben Ali; Burc, Muammer; Gungor, Oznur
In the present study electrochemical detection of alpha-lipoic acid (alpha-LA) was carried out with a poly(Vanillin) modified platinum electrode p(VA)/PtE in Brinton Robinson buffer (BR) solution. The platinum electrode surface's was modified with cyclic voltammetry method. The prepared Pt electrode was characterized by cyclic voltammetry in ferrocyanide and scanning electron microscopy (SEM) images. The number of cycles and scan rate effects were studied using square wave voltammetry (SWV) in BR buffer containing 1 mM alpha-LA. The electrochemical oxidation of alpha-lipoic acid on the modified Pt electrode is influenced by the pH and it is an irreversible reaction in which one electron and one proton are transferred. Electrolyte type and pH effect were studied. The anodic peak current shows a linear increase with alpha-LA concentrations ranging from 0.03 mM to 2.00 mM at pH 5, the detection limit being of 0.025 mM. The alpha-lipoic acid quantification in synthetic urine samples was made by SWV with the modified Pt electrode.
Voltammetric determination of alpha lipoic acid using chitosan-based polyurethane membrane electrode
(Elsevier Sci Ltd, 2021) Gungor, Oznur; Kilic, Beyza; Karasurmeli, Tugce Seren; Ozcan, Imren; Koytepe, Suleyman
In this study, chitosan-based polyurethane (PU) membrane modified electrodes were prepared for sensitive, practical and fast measurement of alpha-lipoic acid (ALA), which is an important biomolecule. PU membranes were synthesized using hexamethylene diisocyanate, chitosan, caffeic acid and polyethylene glycol compounds. Chemical structure, thermal stability and morphological properties of the prepared PU membranes were determined with different instrumental techniques. Surface morphology, wettability and hydrophilicity of synthesized chitosan-based PU membranes were investigated. Gold electrode was modified by these PU membranes with different film thicknesses. The bare and PU membrane coated electrodes were used for deduction of ALA by cyclic voltammetry, differential pulse voltammetry and amperometry techniques. In addition, sensitivity, linearity, repeatability and deduction limit of PU modified electrodes were investigated. Modified electrodes showed wide linear detection range (5-200 mu molL(-1)), low detection limit (4.931 mu molL(-1)) and short response time. Results show that polyurethane modified electrodes are good alternative for ALA determination.
Voltammetric Determination of Curcumin in Spices using Platinum Electrode Electrochemically Modified with Poly(Vanillin-co-Caffeic Acid)
(Univ Tehran, Fac Chemistry, Center Excellence Electrochemistry, 2020) Burc, Muammer; Gungor, Oznur; Duran, Serap Titretir
In this study a simple, highly sensitive, and selective electrochemical method was developed for determination of the low concentration curcumin (CUR) using a poly(vanillin-co-caffeic acid) p(Van-CA) modified platinum electrode. Electrode modification was carried out electrochemically with cyclic voltammetry (CV) method. For this purpose; a solution of 6 mM vanillin (Van) and 6 mM caffeic acid (CA) in phosphate buffer solution (PB) adjusted to pH 7.4 was used. Then, electrochemical behaviour of CUR on the platinum electrode modified with p(Van-CA) was investigated by using CV and differential pulse voltammetry (DPV) methods. Tween 20 as surfactant was used to increase the solubility and stability of CUR in this study. CUR responses of the modified electrode showed that it was selective, sensitive and stable. A linear calibration graph was acquired in the high concentration range of 0.1 to 1.0 mM CUR. Correlation coefficient (R-2) was calculated as 0.9951 from this linear calibration curve. The correlation coefficient for the low concentration range 0.01 to 0.07 mM was also calculated from 0.9950. LOD (limit of detection) and LOQ (limit of quantitation) of the developed method were determined as 0.005 mM and 0.015 mM, respectively. However, the detection of CUR in spices samples was made with this method. The recovery efficiency of the p(Van-CA) modified Pt electrode (p(Van-CA)/PtE) was calculated range of 96% and 102% for three different spices samples. Finally; developed method has been shown that it has fast, low cost, simple, reproducible, high accuracy and precision (99.6%) for sensitive and selective determination of CUR by using p(Van-CA)/PtE as effective novel electrode.

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