Cristina Radulescu
CS II - Centrul de Bioanaliză
Biografie
Începând din anul 2008, fac parte din echipa Centrului de Bioanaliză al INCDSB București, unde desfășor activități de cercetare în domeniul senzorilor și biosenzorilor. În principal, m-am concentrat pe dezvoltarea de instrumente analitice și metode electrochimice pentru detecţia metalelor grele din diverse probe, dezvoltarea și caracterizarea electrozilor chimic modificați, precum şi dezvoltarea de metode de analiză prin injectare în flux şi biosenzori enzimatici pentru analiza probelor de alimente şi de mediu.
Am participat ca membru în echipa de cercetare la numeroase proiecte de cercetare-dezvoltare și am îndeplinit rolul de responsabil de proiect în proiectul național PNII – BLUEBOXSENS – Dezvoltarea și caracterizarea unor senzori moleculari pe bază de derivați de ciclobis(paraquat-p-fenilen) utilizați pentru detecţia și identificarea factorilor generatori de crize (substanțe periculoase și prioritar periculoase).
De asemenea, am fost responsabil de faza în cadrul proiectului Nucleu (BIODIVERS 3) pentru realizarea unui sistem electrochimic de control al contaminării cu metale grele a materiilor prime și monitorizare a fluxului tehnologic de obținere a fitoprodusilor.
Publicatii
Publication | Authors | Date | |
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article
Acetylcholinesterase And Butyrylcholinesterase Co-Immobilized On A Copper Containing Prussian Blue Modified Electrode For The Broad Screening Of Insecticides |
Bucur Madalina-Petruta; Radulescu Maria-Cristina; Bucur Bogdan; Radu Gabriel Lucian | Analytical And Bioanalytical Chemistry, 2024 | |
RezumatWe have developed a bienzymatic biosensor that contains acetylcholinesterase together with butyrylcholinesterase co-immobilized on the same electrode modified with a stabilized copper containing Prussian blue electrodeposited on electrodes coated with 4-aminothiophenol monolayer using diazonium chemistry and copper nanoparticles for improved sensitivity. There are organophosphorus and carbamate neurotoxic insecticides that inhibit only one of the two enzymes, e.g., pirimicarb inhibits butyrylcholinesterase at much lower concentrations than acetylcholinesterase while methomyl inhibits only acetylcholinesterase. Our system is simple and in a single measurement provides a sensitive signal for insecticides' presence based on the inhibition of the enzyme with the highest affinity for each toxic compound. The limits of detection are 50 ng/mL pirimicarb for the bienzymatic biosensor in comparison with 400 ng/mL pirimicarb for the acetylcholinesterase biosensor and 6 ng/mL methomyl for the bienzymatic biosensor, while inhibition is obtained for the butyrylcholinesterase biosensor at 700 ng/mL. |
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article
Acetylcholinesterase And Butyrylcholinesterase Co-Immobilized On A Copper Containing Prussian Blue Modified Electrode For The Broad Screening Of Insecticides |
Bucur M.-P.; Radulescu M.-C.; Bucur B.; Radu G.L. | Analytical And Bioanalytical Chemistry, 2024 | |
RezumatWe have developed a bienzymatic biosensor that contains acetylcholinesterase together with butyrylcholinesterase co-immobilized on the same electrode modified with a stabilized copper containing Prussian blue electrodeposited on electrodes coated with 4-aminothiophenol monolayer using diazonium chemistry and copper nanoparticles for improved sensitivity. There are organophosphorus and carbamate neurotoxic insecticides that inhibit only one of the two enzymes, e.g., pirimicarb inhibits butyrylcholinesterase at much lower concentrations than acetylcholinesterase while methomyl inhibits only acetylcholinesterase. Our system is simple and in a single measurement provides a sensitive signal for insecticides’ presence based on the inhibition of the enzyme with the highest affinity for each toxic compound. The limits of detection are 50 ng/mL pirimicarb for the bienzymatic biosensor in comparison with 400 ng/mL pirimicarb for the acetylcholinesterase biosensor and 6 ng/mL methomyl for the bienzymatic biosensor, while inhibition is obtained for the butyrylcholinesterase biosensor at 700 ng/mL. Graphical Abstract: (Figure presented.) © The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature 2024. |
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article
Cavitation-Effect-Based Treatments And Extractions For Superior Fruit And Milk Valorisation |
Bucur Madalina-Petruta; Radulescu Maria-Cristina; Radu Gabriel Lucian; Bucur Bogdan | Molecules, 2023 | |
RezumatUltrasound generates cavities in liquids with high-energy behaviour due to large pressure variations, leading to (bio)chemical effects and material modification. Numerous cavity-based treatments in food processes have been reported, but the transition from research to industrial applications is hampered by specific engineering factors, such as the combination of several ultrasound sources, more powerful wave generators or tank geometry. The challenges and development of cavity-based treatments developed for the food industry are reviewed with examples limited to two representative raw materials (fruit and milk) with significantly different properties. Both active compound extraction and food processing techniques based on ultrasound are taken into consideration. |
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article
Electrochemical Detection Of Heavy Metals In Raw Materials Using A Glassy Carbon Electrode Modified With 4-Aminothiophenol |
Radulescu Maria-Cristina; Bucur Madalina-Petruta; Bucur Bogdan; Radu Gabriel Lucian | Journal Of The Electrochemical Society, 2022 | |
RezumatSensitive and stable electrodes modified with 4-aminothiophenol were developed for heavy metal detection based on coordination bonds between thiol moieties and analyte. The electrodes were modified using diazonium chemistry in one step modification protocol. The presence of 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) in the electrodeposition media avoids the formation of multilayers and improves the performances due to low surface passivation and good electrochemical transfer at the interface with the solution. Electrodeposition of the organic layer on the electrode surface by chronopotentiometry allowed a good control of the electrode modification process, avoids passivation, and leads to reproducible layers with improved characteristics in comparison with modifications carried out by cyclic voltammetry or chronoamperometry. The electrode was able to detect Pb(II) by differential pulse voltammetry with a linear range of 2.5-400 mu g l(-1) and the detection limit of 1.2 mu g l(-1) and Cd(II) with the calibration line in the range of 2.5-400 mu g l(-1) and a detection limit of 1.5 mu g l(-1). Low interferences were observed and the electrodes were applied for analysis of real samples: fruits pomace and waters. (C) 2022 The Electrochemical Society (ECS). Published on behalf of ECS by IOP Publishing Limited. |
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article
Rapid Determination Of 5-Nitrofuran Ring Antibiotics In Complex Samples Using A Boron-Doped Diamond Electrode And Differential Pulse Voltammetry |
Radulescu Maria-Cristina; Bucur Madalina-Petruta; Bucur Bogdan; Radu Gabriel Lucian | Analytical Letters, 2021 | |
RezumatA rapid, simple, and precise electrochemical method was developed for the determination of the total content of antibiotics containing a 5-nitrofuran ring with antibacterial activity including furazolidone, nitrofurazone, nitrofurantoin, and furaltadone in several samples. Boron-doped diamond electrode was used as the working electrode. The electrochemical properties of these compounds were evaluated by cyclic voltammetry. A differential pulse voltammetric method based on the cathodic reduction at high potentials was used for the determination of the total nitrofuran content in a mixture at pH 6.47. The voltammetric measurements showed that the proposed electrochemical method was able to identify the nitrofurazone from a mixture of antibiotics based on its anodic oxidation in alkaline medium (pH 10.6). This method presented good accuracy (between 94.5 and 102.5%) and precision (less than 3.94%), with calibration graphs starting from 50 nmol L-1. The method was applied with success for the determination of total content of compounds with 5-nitrofuran ring and for the selective determination of nitrofurazone in pharmaceutical tablets and food products (milk and honey) without pretreatment of the samples. |
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article
Ester Flavorants Detection In Foods With A Bienzymatic Biosensor Based On A Stable Prussian Blue-Copper Electrodeposited On Carbon Paper Electrode |
Radulescu Maria-Cristina; Bucur Madalina-Petruta; Bucur Bogdan; Radu Gabriel Lucian | Talanta, 2019 | |
RezumatA stable and reproducible layer of Prussian blue (PB) modified with copper was electrodeposited on carbon paper electrodes for the multiple detection of ester flavorants with a bienzymatic biosensor. Carbon fiber composite paper was investigated as high-surface, low-cost substrate for biosensor development. The pre-activation of the electrode surface by cyclic voltammetry was necessary to improve the electrochemical properties before the electrochemical deposition of Prussian blue-copper film (PB-Cu). The stability and the reproducibility of the obtained PB-Cu carbon paper electrode was demonstrated at pH 7.4, optimum for biosensor development. The developed biosensor is based on the immobilization of two enzymes (carboxyl esterase and alcohol oxidase) by cross-linking with glutaraldehyde onto PB-Cu carbon paper electrode. A mixture of key aroma ester compounds (methyl butyrate, ethyl butyrate, methyl cinnamate and ethyl cinnamate) was detected in several food samples with low interferences. |
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conference
Flavors Detection In Foods With A Bi-Enzymatic Biosensor Based On A Stable Pb-Cu Film/Carbon Paper Electrode |
Radulescu M.C.; Bucur; P.M.; Bucur; B.; Radu; G.L. | Prioritatile Chimiei Pentru O Dezvoltare Durabila – Priochem Editia A-Xiv-A, Bucuresti/Romania, 2018 | |
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conference
Carbon Fiber Composite Paper Electrodes Modified With Stable Prussian Blue-Copper Used For Bienzymatic Determination Of Sweeteners In Food |
Bogdan B.;Radu G.L.;Radulescu M.C.;Bucur M.P. | 8Th International Conference On Electrochemistry In Nanosciences: Electrochemistry For Nano & Nano For Electrochemistry, Nancy/Franta, 2018 | |
Rezumat |
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patent
Materiale Nanostructurate Polimetalice Cu Formula Generala M1Xm2Yma100-X-Y, Procedeu De Obtinere A Acestora Si Utilizarea Lor Ca Si Catalizatori Pentru Electro-Oxidarea Combustibililior Organici Cu Formula Mica |
Buhalteanu L.; Covaci O.I.; Dumitrescu D.G.; Mantea C.M.; Mitran R.A.; Radulescu M.C. | State Office For Inventions And Trademarks (Osim), 2018 | |
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article
Low-Interferences Determination Of The Antioxidant Capacity In Fruits Juices Based On Xanthine Oxidase And Mediated Amperometric Measurements In The Reduction Mode |
Bucur Madalina-Petruta; Radulescu Maria-Cristina; Bucur Bogdan; Radu Gabriel Lucian | Analytical Sciences, 2016 | |
RezumatA low-interferences enzymatic sensor for evaluating the antioxidant capacity was developed. Xanthine oxidase was used to produce superoxide radicals that spontaneously dismutate to hydrogen peroxide. Low xanthine concentrations were used to minimize the rapid dismutation of the superoxide radical before its fast reaction with antioxidants. The sensor operates in the reduction mode, and evaluations with low interferences of the antioxidant capacity are based on the detection of remaining hydrogen peroxide using Prussian blue electrodes at low potentials. The linear calibration graph is between 2 - 10 mu M ascorbic acid. No interferences were observed from easily oxidisable substances including uric acid, which is produced in the enzymatic reaction or other substances usually found in foods. The method was used to evaluate the antioxidant capacity in different real juice samples. |
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article
Electrochemical Determination Of Hydrogen Peroxide Using A Prussian Blue-Copper Modified Platinum Microelectrode |
Radulescu Maria-Cristina; Bucur Madalina-Petruta; Alecu Andreia; Bucur Bogdan; Radu Gabriel Lucian | Analytical Letters, 2016 | |
RezumatPrussian blue modified with copper was electrodeposited on a platinum microelectrode for the amperometric determination of hydrogen peroxide at -50 mV. The Prussian blue-copper layer was stable for 2 h at pH 7.4 and a storage period of 2 months. The Prussian blue-copper modified microelectrodes were used to develop oxidase based microbiosensors for ethanol and lactate. Lactate and alcohol oxidases were immobilized by cross-linking with glutaraldehyde. No interferences were observed from possible interfering compounds up to a concentration of 0.5 mM. The calibration plot of the lactate microbiosensor was linear between 0.005 and 0.2 mM with a limit of detection of 0.0035 mM lactate. The linear dynamic range of the alcohol microbiosensor was between 0.05 and 2 mM and the limit of detection was 0.02 mM ethanol. The developed microbiosensors were used for the analysis of pickled cucumber juice, yogurt, and wine. |
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article
Formation Of Pure-Phase W2C Nanoparticles Through Carbothermal Reduction In The Presence Of Pd(0) Nanoparticles |
Mitran Raul-Augustin; Radulescu Maria-Cristina; Buhalteanu Lucian; Tanase Liviu Cristian; Dumitrescu Dan George; Matei Cristian | Journal Of Alloys And Compounds, 2016 | |
RezumatThe direct synthesis from elements of tungsten semicarbide, W2C, taking place in a narrow concentration range and at high temperatures, is unsuited for some applications requiring small particle sizes. We report an efficient synthesis method for obtaining pure phase W2C at low temperatures (< 1050 degrees C), through the carbothermal reduction of tungsten oxide species in the presence of metallic palladium nanoparticles obtained in situ. A 1:5 (at.) Pd:W ratio or higher yields pure phase W2C, while increasing the Pd content decreases the carburization temperature. The resulting composite materials contain Pd(0) and W2C particles well-dispersed on carbon, with sizes between 50 and 500 nm. The samples have been tested using cyclic voltammetry and chronoamperometry as potential anode materials for the electrooxidation of formic acid and show improved stability in comparison with commercial Pd and comparable current densities, up to 2 times higher than the commercial catalyst. (C) 2016 Elsevier B.V. All rights reserved. |
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conference
Polyphenols, Radical Scavenger Activity, Short-Chain Organic Acids And Heavy Metals Of Several Plants Extracts |
Teodor E.D.; Lițescu S.C.; Albu C.; Rădulescu C.M.; Chira A.; Gatea F.; Radu G.L. | Inaugurarea Centrului Internațional De Studii Avansate Pentru Sisteme Fluvii-Mări „Danubius-Ri” , Murighiol, Tulcea, 2015 | |
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conference
Stable Prussian Blue-Copper Modified (Micro)Electrodes For Sensitive Enzymatic Biosensors Based On Oxidases |
Radulescu M.C.; Bucur M.P.; Bucur B.; Radu G.L. | Seventh International Workshop On « Biosensors For Food Safety And Environmental Monitoring „ Erfoud, Maroc, 2015 | |
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article
Biosensor Based On Inhibition Of Monoamine Oxidases A And B For Detection Of Beta-Carbolines |
Radulescu Maria-Cristina; Bucur Madalina-Petruta; Bucur Bogdan; Radu Gabriel Lucian | Talanta, 2015 | |
Rezumatbeta-Carbolines are inhibitors of monoamine oxidases (MAO-A and MAO-B) and can be found in foods, hallucinogenic plant or various drugs. We have developed a fast analysis method for beta-carbolines based on the inhibition of MAO. The enzymes were immobilized on screen-printed electrodes modified with a stabilized film of Prussian blue that contain also copper. We have used benzylamine as substrate for the enzymatic reaction and the hydrogen peroxide was measured amperometrically at -50 mV. The detection limits obtained were 5.0 mu M for harmane and 2.5 mu M for both harmaline and norharmane. The MAO-A is inhibited by all three tested beta-carbolines (harmane, norharmane, and harmaline) while MAO-B is inhibited only by norharmane. The presence of norharmane in mixtures of beta-carbolines can be identified based on the difference between the cumulative inhibition of MAO-A by all beta-carbolines and MAO-B inhibition. The developed biosensors were used for food analysis. (C) 2015 Elsevier B.V. All rights reserved. |
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article
Polyphenols, Radical Scavenger Activity, Short-Chain Organic Acids And Heavy Metals Of Several Plants Extracts From Bucharest Delta |
Teodor Eugenia Dumitra; Gatea Florentina; Albu Camelia; Radulescu Cristina Maria; Chira Ana; Radu Gabriel Lucian | Chemical Papers, 2015 | |
RezumatSome plants collected (Mentha aquatica, Bidens tripartita and Ambrosia artemisiifolia) from an unusual habitat developed in recent years in Bucharest (the so-called Bucharest Delta) and the contents of polyphenolic compounds, short-chain organic acids and heavy metals, and radical scavenger activity, were determined. 12 polyphenolic compounds and 7 short-chain organic acids were quantified using high-performance liquid chromatography and capillary electrophoresis; Mentha aq. extracts presented the highest levels of rosmarinic acid (1.58 mg g(-1)) and ferulic acid (2.84 mg g(-1)) and Bidens extracts presented the highest concentrations of chlorogenic acid (0.44 mg g(-1)); the same extracts contain the most important levels of luteolin (0.52 mg g(-1)) or other flavonoids. All the heavy metals detected in the plants studied were found in very low levels (the highest was Pb(II) in Mentha aquatica, (12.84 +/- 0.48) mu g kg(-1)). The study sought to identify the active compounds and some contaminants in plants collected from the Bucharest Delta with the intention of eventual exploitation of the habitat and to enhance the knowledge of such human-modified ecosystems. (C) 2015 Institute of Chemistry, Slovak Academy of Sciences |
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article
Polyphenols, Radical Scavenger Activity, Short-Chain Organic Acids And Heavy Metals Of Several Plants Extracts From "Bucharest Delta" |
Teodor E.D.; Gatea F.; Albu C.; Radulescu C.M.; Chira A.; Radu G.L. | Chemical Papers, 2015 | |
RezumatSome plants collected (Mentha aquatica, Bidens tripartita and Ambrosia artemisiifolia) from an unusual habitat developed in recent years in Bucharest (the so-called "Bucharest Delta") and the contents of polyphenolic compounds, short-chain organic acids and heavy metals, and radical scavenger activity, were determined. 12 polyphenolic compounds and 7 short-chain organic acids were quantified using high-performance liquid chromatography and capillary electrophoresis; Mentha aq. extracts presented the highest levels of rosmarinic acid (1.58 mg g-1) and ferulic acid (2.84 mg g-1) and Bidens extracts presented the highest concentrations of chlorogenic acid (0.44 mg g-1); the same extracts contain the most important levels of luteolin (0.52 mg g-1) or other flavonoids. All the heavy metals detected in the plants studied were found in very low levels (the highest was Pb(II) in Mentha aquatica, (12.84 ± 0.48) μg kg-1). The study sought to identify the active compounds and some contaminants in plants collected from the "Bucharest Delta" with the intention of eventual exploitation of the habitat and to enhance the knowledge of such human-modified ecosystems. © 2015 Institute of Chemistry, Slovak Academy of Sciences. |
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article
Biosensor Based On Inhibition Of Monoamine Oxidases A And B For Detection Of Β-Carbolines |
Radulescu M.-C.; Bucur M.-P.; Bucur B.; Radu G.L. | Talanta, 2015 | |
Rezumatβ-Carbolines are inhibitors of monoamine oxidases (MAO-A and MAO-B) and can be found in foods, hallucinogenic plant or various drugs. We have developed a fast analysis method for β-carbolines based on the inhibition of MAO. The enzymes were immobilized on screen-printed electrodes modified with a stabilized film of Prussian blue that contain also copper. We have used benzylamine as substrate for the enzymatic reaction and the hydrogen peroxide was measured amperometrically at -50 mV. The detection limits obtained were 5.0 μM for harmane and 2.5 μM for both harmaline and norharmane. The MAO-A is inhibited by all three tested β-carbolines (harmane, norharmane, and harmaline) while MAO-B is inhibited only by norharmane. The presence of norharmane in mixtures of β-carbolines can be identified based on the difference between the cumulative inhibition of MAO-A by all β-carbolines and MAO-B inhibition. The developed biosensors were used for food analysis. © 2015 Elsevier B.V. All rights reserved. |
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conference
Biosensor Based On Inhibition Of Monoamine Oxidases A And B For Detection Of B-Carbolines |
Radulescu M.C.; Bucur B.; Bucur M.P.; Radu G.L. | Elsedima International Conference, Oral Communication, Cluj-Napoca, Romania, 2014 | |
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conference
Carboline Analysis With An Amperometric Biosensor Based On Monoamine Oxidase Inhibition |
Radulescu M.C.; Bucur B.; Bucur M.P.; Radu G.L. | New Trends On Sensing-Monitoring-Telediagnosis For Life Sciences, Brasov, Romania, 2014 | |
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conference
Electrochemically Modified Electrodes With Synthesized 4.4’-Bipyridine Derivatives |
Chira A.; Bucur B.; Radulescu M.C.; Radu G.L. | French-Romanian Meeting In The Frame Of Third Edition Of International Conferences On Analytical And Nanoanalytical Methods For Biomedical And Environmental Sciences, Brasov, Romania, 2014 | |
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conference
Low Interferences Determination Of Antioxidant Capacity Based On Xanthine Oxidase And Mediated Amperometric Measurements In Reduction Mode |
Bucur M.P.; Bucur B.; Radulescu M.C.; Radu G.L. | Spq-Analitica-2014-Coimbra, Portugal, 2014 | |
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conference
Polyphenols, Radical Scavenger Activity, Short-Chain Organic Acids And Contaminants From Several Plants Extracts From `Bucharest Delta |
Teodor E.D.; Albu C.; Gatea F.; Rădulescu C.M.; Chira A.; Radu G.L. | Pse Meeting – Phytochemicals In Medicine And Pharmacognosy, Piatra Neamt, Romania, 2014 | |
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article
Bienzymatic Biosensor For Rapid Detection Of Aspartame By Flow Injection Analysis |
Radulescu Maria-Cristina; Bucur Bogdan; Bucur Madalina-Petruta; Radu Gabriel Lucian | Sensors, 2014 | |
RezumatA rapid, simple and stable biosensor for aspartame detection was developed. Alcohol oxidase (AOX), carboxyl esterase (CaE) and bovine serum albumin (BSA) were immobilised with glutaraldehyde (GA) onto screen-printed electrodes modified with cobalt-phthalocyanine (CoPC). The biosensor response was fast. The sample throughput using a flow injection analysis (FIA) system was 40 h(-1) with an RSD of 2.7%. The detection limits for both batch and FIA measurements were 0.1 mu M for methanol and 0.2 mu M for aspartame, respectively. The enzymatic biosensor was successfully applied for aspartame determination in different sample matrices/commercial products (liquid and solid samples) without any pre-treatment step prior to measurement. |
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article
Study Of Electrochemically Modified Electrode With Synthesized N-Benzyl-4,4 '-Bipyridine With Anti-Fouling Properties For Oxygen And Hydrogen Peroxide Detection |
Chira Ana; Bucur Bogdan; Radulescu Maria-Cristina; Galaon Toma; Radu Gabriel-Lucian | International Journal Of Electrochemical Science, 2014 | |
Rezumat1-[(4-nitrophenyl) methyl]-4,4'-bipyridinium (N-PMB) was synthesized by refluxing 4,4'-bipyridine and 4-nitrobenzylchloride. A stable film of 1-phenylmethyl-4,4'-bipyridine (PMB) was successfully electrografted on glassy carbon electrodes by the reduction of the diazonium moieties generated in situ. High antifouling ability was obtained for the PMB modified electrode which makes it a useful sensor device for environmental waters monitoring. The modified electrode was used as an amperometric sensor for mediated hydrogen peroxide detection at -0.5 V. The calibration curve was linear from 5 to 60 mu M H2O2 (R-2=0.9978, n=7) with a detection limit of 0.25 mu M. PMB modified electrodes was able to detect oxygen in river water with good sensitivity, selectivity and reproducibility. |
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article
Study Of Electrochemically Modified Electrode With Synthesized N-Benzyl-4,4'-Bipyridine With Anti-Fouling Properties For Oxygen And Hydrogen Peroxide Detection |
Chira A.; Bucur B.; Radulescu M.-C.; Galaon T.; Radu G.-L. | International Journal Of Electrochemical Science, 2014 | |
Rezumat1-[(4-nitrophenyl)methyl]-4,4'-bipyridinium (N-PMB) was synthesized by refluxing 4,4'-bipyridine and 4-nitrobenzylchloride. A stable film of 1-phenylmethyl-4,4'-bipyridine (PMB) was successfully electrografted on glassy carbon electrodes by the reduction of the diazonium moieties generated in situ. High antifouling ability was obtained for the PMB modified electrode which makes it a useful sensor device for environmental waters monitoring. The modified electrode was used as an amperometric sensor for mediated hydrogen peroxide detection at -0.5 V. The calibration curve was linear from 5 to 60 μM H2O2 (R2=0.9978, n=7) with a detection limit of 0.25 μM. PMB modified electrodes was able to detect oxygen in river water with good sensitivity, selectivity and reproducibility. © 2014 The Authors. Published by ESG. |
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article
Study Of Electrochemically Modified Electrode With Synthesized N-Benzyl-4,4′-Bipyridine With Anti-Fouling Properties For Oxygen And Hydrogen Peroxide Detection |
Chira Ana; Bucur Bogdan; Radulescu Maria-Cristina; Galaon Toma; Radu Gabriel-Lucian | International Journal Of Electrochemical Science, 2014 | |
Rezumat1-[(4-nitrophenyl) methyl]-4,4'-bipyridinium (N-PMB) was synthesized by refluxing 4,4'-bipyridine and 4-nitrobenzylchloride. A stable film of 1-phenylmethyl-4,4'-bipyridine (PMB) was successfully electrografted on glassy carbon electrodes by the reduction of the diazonium moieties generated in situ. High antifouling ability was obtained for the PMB modified electrode which makes it a useful sensor device for environmental waters monitoring. The modified electrode was used as an amperometric sensor for mediated hydrogen peroxide detection at -0.5 V. The calibration curve was linear from 5 to 60 mu M H2O2 (R-2=0.9978, n=7) with a detection limit of 0.25 mu M. PMB modified electrodes was able to detect oxygen in river water with good sensitivity, selectivity and reproducibility. |
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conference
Bi-Enzymatic Biosensor For Rapid Detection Of Aspartame In Commercial Products |
Radulescu M.C.; Bucur B.; Bucur M.P.; Radu G.L. | Sixth International Workshop On “Biosensor For Food Safety And Environmental Monitoring”,Essaouira-Morocco, 2013 | |
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conference
Synthesis Of 4,4’-Dipyridine Derivatives For Immobilization On The Electrode Surface |
Chira A.; Bucur B.; Radulescu M.C.; Radu G.L. | Xxii International Symposium On Bioelectrochemistry And Bioenergetics, Bochum/Germany, 2013 | |
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patent
Metoda Si Aparat Pentru Determinarea Concentratiilor De Mercur |
Danet A.F.; Bratu M.C.; Radulescu (Rizea) M.C.; Bratu A.; Badea M. | State Office For Inventions And Trademarks (Osim), 2012 | |
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patent
Metodă Pentru Determinarea Concentraţiilor De Metanol Şi Etanol Din Amestecuri Fără Separarea Analiţilor |
Radu G. L.; Bucur B.; Bucur M. P.; Rădulescu C. | State Office For Inventions And Trademarks (Osim), 2012 | |
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article
L-Cysteine Determination Based On Tyrosinase Amperometric Biosensors Without Interferences From Thiolic Compounds |
Bucur Madalina Petruta;Bucur Bogdan;Radulescu Cristina Maria;Radu Gabriel Lucian;Covaci Ovidiu Ilie | Analytical Letters, 2010 | |
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article
Determination Of Silver(I) By Differential Pulse Voltammetry Using A Glassy Carbon Electrode Modified With Synthesized N-(2-Aminoethyl)-4,4 '-Bipyridine |
Bucur Madalina Petruta;Bucur Bogdan;Chira Ana;Radulescu Maria-Cristina;Radu Gabriel Lucian;Radulescu Medeea | Sensors, 2010 | |
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article
Determination Of Silver(I) By Differential Pulse Voltammetry Using A Glassy Carbon Electrode Modified With Synthesized N-(2-Aminoethyl)-4,4'-Bipyridine |
Radulescu M.-C.; Chira A.; Radulescu M.; Bucur B.; Bucur M.P.; Radu G.L. | Sensors, 2010 | |
RezumatA new modified glassy carbon electrode (GCE) based on a synthesized N-(2-aminoethyl)-4,4'-bipyridine (ABP) was developed for the determination of Ag(I) by differential pulse voltammetry (DPV). ABP was covalently immobilized on GC electrodes surface using 4-nitrobenzendiazonium (4-NBD) and glutaraldehyde (GA). The Ag(I) ions were preconcentrated by chemical interaction with bipyridine under a negative potential (-0.6 V); then the reduced ions were oxidized by differential pulse voltammetry and a peak was observed at 0.34 V. The calibration curve was linear in the concentration range from 0.05 μM to 1 μM Ag(I) with a detection limit of 0.025 μM and RSD = 3.6%, for 0.4 μM Ag(I). The presence of several common ions in more than 125-fold excess had no effect on the determination of Ag(I). The developed sensor was applied to the determination of Ag(I) in water samples using a standard addition method. © 2010 by the authors. |
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article
Determination Of Silver(I) By Differential Pulse Voltammetry Using A Glassy Carbon Electrode Modified With Synthesized N-(2-Aminoethyl)-4,4′-Bipyridine |
Radulescu Maria-Cristina; Chira Ana; Radulescu Medeea; Bucur Bogdan; Bucur Madalina Petruta; Radu Gabriel Lucian | Sensors, 2010 | |
RezumatA new modified glassy carbon electrode (GCE) based on a synthesized N-(2-aminoethyl)-4,4'-bipyridine (ABP) was developed for the determination of Ag(I) by differential pulse voltammetry (DPV). ABP was covalently immobilized on GC electrodes surface using 4-nitrobenzendiazonium (4-NBD) and glutaraldehyde (GA). The Ag(I) ions were preconcentrated by chemical interaction with bipyridine under a negative potential (-0.6 V); then the reduced ions were oxidized by differential pulse voltammetry and a peak was observed at 0.34 V. The calibration curve was linear in the concentration range from 0.05 mu M to 1 mu M Ag(I) with a detection limit of 0.025 mu M and RSD = 3.6%, for 0.4 mu M Ag(I). The presence of several common ions in more than 125-fold excess had no effect on the determination of Ag(I). The developed sensor was applied to the determination of Ag(I) in water samples using a standard addition method. |