30 results on '"Srikant Sahoo"'
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2. Carbon nano-dot for cancer studies as dual nano-sensor for imaging intracellular temperature or pH variation
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Trilochan Gadly, Goutam Chakraborty, Mrityunjay Tyagi, Birija S. Patro, Bijaideep Dutta, Akhilesh Potnis, Pallavi Chandwadkar, Celin Acharya, Shishu Kant Suman, Archana Mukherjee, Suman Neogy, Amey Wadawale, Srikant Sahoo, Nitish Chauhan, and Sunil K. Ghosh
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Medicine ,Science - Abstract
Abstract Cellular temperature and pH govern many cellular physiologies, especially of cancer cells. Besides, attaining higher cellular temperature plays key role in therapeutic efficacy of hyperthermia treatment of cancer. This requires bio-compatible, non-toxic and sensitive probe with dual sensing ability to detect temperature and pH variations. In this regard, fluorescence based nano-sensors for cancer studies play an important role. Therefore, a facile green synthesis of orange carbon nano-dots (CND) with high quantum yield of 90% was achieved and its application as dual nano-sensor for imaging intracellular temperature and pH was explored. CND was synthesized from readily available, bio-compatible citric acid and rhodamine 6G hydrazide using solvent-free and simple heating technique requiring purification by dialysis. Although the particle size of 19 nm (which is quite large for CND) was observed yet CND exhibits no surface defects leading to decrease in photoluminescence (PL). On the contrary, very high fluorescence was observed along with good photo-stability. Temperature and pH dependent fluorescence studies show linearity in fluorescence intensity which was replicated in breast cancer cells. In addition, molecular nature of PL of CND was established using pH dependent fluorescence study. Together, the current investigation showed synthesis of highly fluorescent orange CND, which acts as a sensitive bio-imaging probe: an optical nano-thermal or nano-pH sensor for cancer-related studies.
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- 2021
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3. rGO/ReO3 nano composite modified electrode for the ultra-sensitive determination of dopamine and uric acid
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Sudipa Manna, Sriram Kumar, Abhishek Sharma, Srikant Sahoo, M.K. Dey, P.K. Mishra, and A.K. Satpati
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Dopamine ,Uric acid ,Ascorbic acid ,ReO3 ,rGO ,Voltammetry ,Biotechnology ,TP248.13-248.65 - Abstract
Development of suitable modified electrode in generating the electrochemical signals from dopamine (DA), uric acid (UA) and ascorbic acid (AA) has remained challenging issue even after decades of research in the related field. Under the present investigation the perovskite type metal oxide nano particle has been used in the form of composite with the reduced graphene oxide (rGO) as the active material for sensing. The superior electrical conductivity of Rhenium oxide (ReO3) combined with the adsorptive and conducting nature of rGO has been utilised in enhancing the electrochemical responses form the molecules. Thin films of Nafion was used over the rGO/ReO3 composite materials for stabilization of the modification. The electron transfer property of the molecules has been evaluated from the cyclic voltammetry and electrochemical impedance measurements. The standard electron transfer rate constants have been obtained from the Laviron formulations of the cyclic voltammetry measurements. Simultaneous electrochemical response has been obtained from the three molecules over the rGO/ReO3 nano composite modified electrode, the analytical method has been developed with the detection limit (S/N = 3) of 0.08 nM, 0.06 μM and 0.89 μM for DA, UA and AA respectively. For simultaneous determination however, the determination of DA and UA has been proposed and the interference test was carried out through simultaneous detection of the signals of the molecules. The analytical method has been applied for the detection of analytical signals of DA and UA in synthetic serum samples through spiked recovery test.
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- 2022
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4. Electrochemical characteristics of prednisone and its interaction with dsDNA over functionalized CNSs modified electrode
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Srikant Sahoo and A.K. Satpati, PhD
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Voltammetry ,Prednisone ,dsDNA ,Cu2+ ,Binding constant ,Spectroelectrochemistry ,Biotechnology ,TP248.13-248.65 - Abstract
Herein the electrochemical property of prednisone, a synthetic corticosteroid drug has been investigated using carbon nano sphere (CNSs) modified glassy carbon electrode (GCE) in neutral phosphate buffer medium at pH 7.2. CNSs are functionalized with acidic functional groups and the GCE has been modified with these functionalized CNSs. Significant enhancement in the electrochemical property has been observed while modifying the GCE using the functionalized CNSs. The reduction process of the prednisone over the modified electrode is found to be pH dependent and shows 2e− and 2H+ proton transfer electrochemical reduction kinetics. Interaction of prednisone with transition metal ions (Cu2+) is investigated in the line to understand the biological functioning correlated with the interaction of dsDNA and the transition metal ion Cu2+. The deviation of the electrochemical signal of prednisone due to the presence of some commonly occurring chemical systems has also been investigated. An analytical method of determination of prednisone has been developed using the square wave voltammetric techniques in 0.1 M PBS buffer solution at pH 7.2 and the detection limit obtained as 73 nM.
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- 2022
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5. Incorporation of Carbon Quantum Dots for Improvement of Supercapacitor Performance of Nickel Sulfide
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Srikant Sahoo, Ashis Kumar Satpati, Prasanta Kumar Sahoo, and Prakash Dattatray Naik
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Chemistry ,QD1-999 - Published
- 2018
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6. Determination of impurities in copper metal using total reflection X‐ray fluorescence spectrometry after matrix separation: Method validation and uncertainty assessment
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Srikant Sahoo, Ashis K. Satpati, Kallola K. Swain, P.S. Remya Devi, Trupti A. Chavan, and Madhusudan Ghosh
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Total internal reflection ,Materials science ,Impurity ,Copper metal ,Analytical chemistry ,X-ray fluorescence ,Mass spectrometry ,Matrix separation ,Spectroscopy - Published
- 2021
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7. Prussian Blue Nanocubes‐SnO 2 Quantum Dots‐Reduced Graphene Oxide Ternary Nanocomposite: An Efficient Non‐noble‐metal Electrocatalyst for Non‐enzymatic Detection of H 2 O 2
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Prasanta Kumar Sahoo, Seema Chauhan, Chhaya Sharma, Ashis K. Satpati, and Srikant Sahoo
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Prussian blue ,Materials science ,Nanocomposite ,Graphene ,Oxide ,Electrocatalyst ,Analytical Chemistry ,law.invention ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Quantum dot ,law ,Electrochemistry ,Hydrogen peroxide ,Ternary operation - Published
- 2020
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8. Probing the interaction of anti-HIV drug Darunavir with dsDNA and HSA using electrochemical and spectroscopic measurements
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Priyanka R. Ipte, Sudipa Manna, Srikant Sahoo, and Ashis Kumar Satpati
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Environmental Engineering ,Anti-HIV Agents ,Humans ,HIV Infections ,Serum Albumin, Human ,General Medicine ,DNA ,Electrodes ,Darunavir - Abstract
Investigation of electrochemical and spectroscopic characteristics of anti-human immunodeficiency virus (HIV) drug provides important information related to the efficacy of the drug in relation with its interaction with several important biomolecules. In the present investigation we have developed an electrochemical and spectroscopic method for the detection of anti-HIV drug Darunavir (DRV) using the carbon paste as the working electrode. The analytical method has generated the detection limit of 1.86 µM (S/N = 3). The electrochemical investigations have also been carried out for the exploration of the interaction of DRV with double stranded deoxyribose nucleic acid DNA (dsDNA) and human serum albumin (HSA). Electrochemical investigations were supported from the spectroscopic measurements in evaluating the interaction. The results obtained from voltammetric and spectroscopic experiments shows strong interaction between the drug and the macromolecules. It has been observed that DRV forms strong complexes with HSA and dsDNA with the formation constants of 2.7 × 10
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- 2022
9. Construction of Isoenergetic Band Alignment between CdS QDs and CaFe2O4@ZnFe2O4 Heterojunction: A Promising Ternary Hybrid toward Norfloxacin Degradation and H2 Energy Production
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Debasmita Kandi, Srikant Sahoo, Kulamani Parida, and Arjun Behera
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Materials science ,Clean water ,Nanotechnology ,Heterojunction ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Nanomaterials ,General Energy ,Photocatalysis ,Degradation (geology) ,Physical and Theoretical Chemistry ,0210 nano-technology ,Ternary operation - Abstract
The increasing demand for clean water triggers advancement in development of nanomaterials for photocatalytic pollutant degradation. Herein, we report for the first time a CdS QDs decorated p-CaFe2...
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- 2019
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10. Electrochemical Characteristics of Prednisone and its Interaction with DsDNA Over Functionalized CNSs Modified Electrode
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Srikant Sahoo and Ashis Kumar Satpati
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History ,Polymers and Plastics ,Business and International Management ,Industrial and Manufacturing Engineering - Published
- 2021
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11. Facile and green synthesis of silver nanoparticle-reduced graphene oxide composite and its application as nonenzymatic electrochemical sensor for hydrogen peroxide
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Srikant Sahoo, Jagdish C. Bhangoji, Ashis K. Satpati, and Suresh S. Shendage
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Graphene ,General Chemistry ,Oxide composite ,Electrocatalyst ,Silver nanoparticle ,Electrochemical gas sensor ,law.invention ,lcsh:Chemistry ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,lcsh:QD1-999 ,law ,Hydrogen peroxide ,Acetonitrile - Abstract
A simple and environment friendly protocol has been developed for the synthesis of Ag nanoparticles (AgNPs) supported on reduced graphene oxide (rGO) with copper metal foil as reductant. The prepared AgNPs-rGO, nanocomposite was characterized by various analytical techniques such as scanning electron microscopy (SEM), field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD). The electrochemical performance of the material has been evaluated using cyclic voltammetry (CV), chronoamperometry and electrochemical impedance spectroscopy (EIS). The average crystallite size of AgNPs is found to be 32.34 nm. The application of prepared electrocatalyst (AgNPs-rGO) as a non-enzymatic sensor is examined through the modified electrode with the synthesized AgNPs-rGO. The sensor showed excellent performance toward H2O2 reduction with a sensitivity of 12.73 µA.cm-2.mM-1, with a linear dynamic range of 1.5 µM – 100 mM, and the detection limit of 1.90 µM (S/N = 3). Furthermore, the sensor displayed high sensitivity, reproducibility, stability and selectivity for the determination of H2O2. The results demonstrated that AgNPs-rGO has potential applications as sensing material for quantitative determination of H2O2.
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- 2021
12. Incorporation of Carbon Quantum Dots for Improvement of Supercapacitor Performance of Nickel Sulfide
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Prasanta Kumar Sahoo, Ashis K. Satpati, Prakash D. Naik, and Srikant Sahoo
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Supercapacitor ,Tafel equation ,Materials science ,Nickel sulfide ,Nanostructure ,General Chemical Engineering ,Composite number ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Capacitance ,Article ,0104 chemical sciences ,lcsh:Chemistry ,chemistry.chemical_compound ,lcsh:QD1-999 ,chemistry ,Chemical engineering ,Quantum dot ,0210 nano-technology ,Carbon - Abstract
A facile hydrothermal method is adopted for the synthesis of hierarchical flowerlike nickel sulfide nanostructure materials and their composite with carbon quantum dot (NiS/C-dot) composite. The composite material exhibited good performance for electrochemical energy-storage devices as supercapacitor with a specific capacity of 880 F g-1 at a current density of 2 A g-1. The material remained stable up to the tested 2000 charge-discharge cycles. Carbon quantum dots of size 1.3 nm were synthesized from natural sources and the favorable electronic and surface property of C-dots were utilized for improvement of the supercapacitor performance of NiS. The results from Tafel analysis, double-layer capacitance, and the impedance measurement reveal that the incorporation of C-dots inside the NiS matrix has improved the charge-transfer process, which is mainly responsible for the enhancement of the supercapacitive property of the composite materials.
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- 2018
13. Supported liquid membrane based loading technique for thermal ionization mass spectrometry: an application to plutonium isotopic composition and concentration determination
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Raju V. Shah, Amol Mhatre, S. Jagadish Kumar, P. G. Jaison, Srikant Sahoo, Radhika M. Rao, Ashok K. Pandey, and Sankararao Chappa
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Capillary flow porometry ,Chemistry ,Health, Toxicology and Mutagenesis ,010401 analytical chemistry ,Public Health, Environmental and Occupational Health ,Analytical chemistry ,Halide ,Microporous material ,Thermal ionization mass spectrometry ,Isotope dilution ,010403 inorganic & nuclear chemistry ,Mass spectrometry ,01 natural sciences ,Pollution ,Diluent ,0104 chemical sciences ,Analytical Chemistry ,Membrane ,Nuclear Energy and Engineering ,Radiology, Nuclear Medicine and imaging ,Spectroscopy - Abstract
Supported liquid membrane (SLM) was prepared by immobilizing the extractant tricaprylmethyl ammonium chloride (Aliquat-336) into the microporous poly(propylene) membrane. The formed SLM with optimize composition was found be selective toward Pu4+ ions over UO22+ and Am3+ ions in a wide range of high acid concentrations (3–7 mol L−1 HNO3). The composition of SLM was optimized by using varying proportions of Aliquat-336 with solvents/diluents such as dioctyl phthalate (DOP), 2-nitrophenyl octyl ether and tris(2-ethylhexyl) phosphate. Among these diluents, DOP was found to be stable and causing uniform distribution of the extractant on the membrane. The surface morphology was characterized by atomic force microscopy. Stability and change in physical structure of SLM was characterized by capillary flow porometry. The Pu pre-concentrated in SLM was used to find out isotopic composition and concentration of the plutonium with help of thermal ionization mass spectrometry. The SLM was found to be stable and amenable to routine analyses.
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- 2018
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14. Electrochemical capacitance properties of cobalt oxide entangled over MWCNT and cobalt oxide AC composites
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Ashis K. Satpati and Srikant Sahoo
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Supercapacitor ,Chemistry ,Scanning electron microscope ,General Chemical Engineering ,Composite number ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,Dielectric spectroscopy ,Nano ,Electrochemistry ,Surface charge ,Cyclic voltammetry ,Composite material ,0210 nano-technology ,Cobalt oxide - Abstract
Composites of cobalt oxide with activated carbon (AC) and multi wall carbon nano tubes (MWCNTs) were synthesised using hydrothermal method. X-ray diffraction and scanning electron microscopy (SEM) has revealed the Co3O4 nano phase well embedded over the AC and MWCNTs matrices. Materials were further characterised using FTIR measurements. Cyclic voltammetry and charge discharge experiments were carried out in 1 M KOH solution. Both the materials have shown superior electrochemical properties and good long time cycle ability. The Co3O4 with MWCNTs composite (Co3O4/MWCNTs) has shown better electrochemical characteristics compared to the composite of Co3O4 with AC (Co3O4/AC) due to the symmetric entanglement of the materials all over the MWCNT surface. The discharge specific capacitance of Co3O4/AC and Co3O4/MWCNTs composites was obtained as 620 and 788 Fg− 1 respectively. The electrochemical performance of the materials was modelled using electrochemical impedance modelling and the results revealed the presence of unsaturated surface charge over the composite electrode surface.
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- 2017
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15. Gold Nano Particle and Reduced Graphene Oxide Composite Modified Carbon Paste Electrode for the Ultra Trace Detection of Arsenic (III)
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Srikant Sahoo, Ashis K. Satpati, and Prasanta Kumar Sahoo
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Materials science ,Graphene ,Scanning electron microscope ,Supporting electrolyte ,Analytical chemistry ,Oxide ,Nanoparticle ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,law.invention ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,law ,Colloidal gold ,Electrode ,Electrochemistry ,0210 nano-technology ,Graphene oxide paper - Abstract
Gold nanoparticles (AuNPs) and reduced graphene oxide (RGO) composite modified carbon paste electrode (CPE) was prepared by electrodepositing AuNPs over the reduced graphene oxide (RGO) modified carbon paste electrode. The composite material was characterised using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and atomic force microscopy (AFM) techniques. The nano composite modified electrode was applied for the determination of total As and for the inorganic speciation of As(III) and As(V) in environmental samples. The linear dynamic range was obtained for the determination of As(III) in the present method from 1μgL−1 to 20 μgL−1 and the limit of detection(LOD) in the standard solution was found to be 0.13 μgL−1 for the 300 sec deposition time in 10 mL supporting electrolyte solution. This method was applied for the determination of As (III) in water and soil samples. The results were agreed well with the result obtained from the hydride generation atomic absorption spectrometry.
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- 2017
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16. Fabrication of rGO/NiS/AuNCs ternary nanocomposite modified electrode for electrochemical sensing of Cr(VI) at utra-trace level
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Ashis K. Satpati and Srikant Sahoo
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Nanocomposite ,Materials science ,Graphene ,General Physics and Astronomy ,02 engineering and technology ,Surfaces and Interfaces ,General Chemistry ,Buffer solution ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Surfaces, Coatings and Films ,law.invention ,Dielectric spectroscopy ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,law ,Electrode ,Cyclic voltammetry ,0210 nano-technology ,Ternary operation ,Voltammetry - Abstract
In the present investigation, ternary nanocomposite of reduced graphene oxide rGO, Nickel sulphde (NiS) and gold nano cube (rGO/NiS/AuNCs) has been synthesized by adopting a facile single step hydrothermal method. The electrochemical interfacial property of the composite materials is obtained from cyclic voltammetry and electrochemical impedance spectroscopy (EIS). The crystal structure, surface morphology and elemental composition of the rGO/NiS/AuNCs ternary nanocomposite are characterized using XRD, SEM and EDX measurements, the characterization of the materials using such techniques have shown the formation of flower shaped NiS and Au in the form of AuNCs, effective formation of composite has been evident from the microscopic and spectroscopic measurements. The square wave voltammetry technique is employed to the determination of Cr(VI) in 0.1 M acetate buffer solution at the optimized pH 5. The influence of various electrochemical parameters affecting the stripping voltammetry are investigated and optimized. Under optimal condition, the limit of detection (LOD) in the present method is found to be 0.09 µgL−1 at the accumulation potential of -0.5V for the duration of 30s. The rGO/NiS/AuNCs ternary nano composite modified electrode showed good stability and high sensitivity towards the detection of Cr(VI) with low response time. The developed method has been applied for the detection of Cr(VI) in environmental samples.
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- 2021
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17. CdS QDs modified BiOI/Bi2MoO6 nanocomposite for degradation of quinolone and tetracycline types of antibiotics towards environmental remediation
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Srikant Sahoo, Kulamani Parida, Debasmita Kandi, and Arjun Behera
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Nanocomposite ,biology ,Precipitation (chemistry) ,Chemistry ,Tetracycline ,Filtration and Separation ,02 engineering and technology ,021001 nanoscience & nanotechnology ,biology.organism_classification ,Analytical Chemistry ,Catalysis ,Contact angle ,020401 chemical engineering ,Zeta potential ,medicine ,Degradation (geology) ,0204 chemical engineering ,0210 nano-technology ,Bacteria ,Nuclear chemistry ,medicine.drug - Abstract
Prevention of future threat of antibiotic-resistant bacteria and genes by elimination of discharged antibiotics from environment pleas for growth of cutting edge technologies with high efficiency. Herein, CdS QDs modified BiOI-Bi doped Bi2MoO6 nanocomposite (BOI-CBBMO) was synthesized by in-situ precipitation deposition method. The unique composite with 3% CdS QDs i.e. BOI-CBBMO-3 exhibits best degradation performance of four ubiquitous antibiotics i.e. 87%, 87% 75% and 93% for tetracycline, oxy-tetracycline, ciprofloxacin, norfloxacin in 60 min of sunlight irradiation and OH is mainly responsible for degradation process. Real environmental factors like pH, inorganic salts are also considered for degradation. The chemical interaction exists between catalyst and antibiotics are ascertained by zeta potential and contact angle experiment. This evidenced hydrophobic-hydrophilic interaction rather electrostatic interaction. Intermediate products are detected Liquid Chromatography-Mass Spectrometry analysis reveals presence of no anti-bacterially active products.
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- 2020
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18. A novel low cost nonenzymatic hydrogen peroxide sensor based on CoFe2O4/CNTs nanocomposite modified electrode
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Ashis K. Satpati, Prasanta Kumar Sahoo, Sudipa Manna, and Srikant Sahoo
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Detection limit ,Nanocomposite ,Chemistry ,General Chemical Engineering ,02 engineering and technology ,Glassy carbon ,Chronoamperometry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,Dielectric spectroscopy ,Chemical engineering ,Electrode ,Nano ,Electrochemistry ,Cyclic voltammetry ,0210 nano-technology - Abstract
A novel and low cost electrochemical method has been developed for the non-enzymatic detection of the hydrogen peroxide using cobalt ferrite (CoFe2O4), carbon nano tubes (CNTs) modified glassy carbon electro (GCE), and the sensor has been named as CoFe2O4/CNTs/GCE. The CoFe2O4/CNTs nanocomposite has been successfully synthesized through a facile one-step hydrothermal method. The crystal structure, morphology and composition of the nanocomposite are characterized by XRD, Raman, XPS, FE-SEM, and HR-TEM measuremnets. The particle size of ferrite nano composite is obtained as ~17 nm. Electrochemical properties of the CoFe2O4/CNTs/GCE are investigated using various electrochemical techniques such as; cyclic voltammetry, electrochemical impedance spectroscopy and square wave voltammetry. The constructed CoFe2O4/CNTs/GCE showed superior electrochemical activity towards H2O2 sensing compared with the CoFe2O4/GCE and bare GCE. The sensor produces a linear response in the range of 5–50 μM and the detection limit is obtained as 0.05 μM (S/N = 3) using chronoamperometry techniques and the square wave voltammetry technique generated the linear response in the range of 5–100 μM and the detection limit of 0.02 μM (S/N = 3). The developed sensor has shown suitable anti-interfering property with good stability towards the detection of H2O2. The CoFe2O4/CNTs modified electrode has been applied to determine H2O2 in the commercially available juice samples. The performance of the sensor is comparable or superior to several others commonly sensors used for the analysis of H2O2, which indicates its promising practical application.
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- 2020
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19. Electrodeposited Bi-Au nanocomposite modified carbon paste electrode for the simultaneous determination of copper and mercury
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Srikant Sahoo, A. V. R. Reddy, and Ashis K. Satpati
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Nanocomposite ,Materials science ,General Chemical Engineering ,Metal ions in aqueous solution ,Inorganic chemistry ,Analytical chemistry ,chemistry.chemical_element ,General Chemistry ,Electrochemistry ,Copper ,Bismuth ,Carbon paste electrode ,Anodic stripping voltammetry ,chemistry ,Electrode - Abstract
Composites of bismuth and gold nanoparticles (Bi–AuNPs) were prepared on a carbon paste electrode (CPE) by an electrochemical deposition method. The electrochemical parameters were optimized for the effective deposition of Bi–AuNP composite materials. Microscopic examination revealed that nanoparticle clusters of gold were embedded well within the bismuth films (Bi films) over the surface of the CPE. An analytical anodic stripping voltammetry method has been developed for the simultaneous determination of copper and mercury at ultratrace levels using the Bi–AuNP modified CPE. It was possible to observe well separated stripping peaks of the two metal ions and the modified electrode was successfully applied for simultaneous determination of Cu and Hg. The limits of detection using the optimized analytical procedure were observed as 0.16 μg L−1 and 0.28 μg L−1 for Cu and Hg respectively. Interference effects of some of the commonly occurring metal ions were investigated and the method was applied for the determination of Cu and Hg in two ground water and two soil samples collected from different places.
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- 2015
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20. Spectro-electrochemistry of ciprofloxacin and probing its interaction with bovine serum albumin
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Ashis K. Satpati, Priyanka R. Ipte, and Srikant Sahoo
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Biophysics ,02 engineering and technology ,Electrochemistry ,01 natural sciences ,Electron transfer ,Adsorption ,Ciprofloxacin ,Animals ,Physical and Theoretical Chemistry ,Bovine serum albumin ,Spectroscopy ,Voltammetry ,biology ,Chemistry ,010401 analytical chemistry ,Serum Albumin, Bovine ,Electrochemical Techniques ,General Medicine ,021001 nanoscience & nanotechnology ,Binding constant ,Anti-Bacterial Agents ,0104 chemical sciences ,biology.protein ,Cattle ,Spectrophotometry, Ultraviolet ,Cyclic voltammetry ,0210 nano-technology ,Protein Binding ,Nuclear chemistry - Abstract
In the present investigation the electrochemical behaviour of the drug, Ciprofloxacin (Cf) and its interaction with the Bovine Serum Albumin (BSA) is reported. UV-Visible Spectroscopy (UV-Vis) and Spectro-electrochemical measurements were carried out to quantify the charge transfer process in Cf. Analysis of the results obtained from cyclic voltammetry (CV) measurements indicated the electrochemical oxidation of Cf followed mixed adsorption and diffusion control process. The spectro-electrochemical investigations were carried out and the modification of the spectral peaks were monitored to obtain the mechanism of the electrochemical oxidation process of Cf. Interaction of Cf with Bovine Serum Albumin (BSA) were investigated using electrochemical, spectroscopic and spectro-electrochemical experiments. Important electro-kinetic parameters like; the electron transfer property, binding constant and diffusivity of the Cf/BSA complex were investigated. Electrochemistry with an ultra-microelectrode was utilised to investigate the diffusivity of the drug and its complex with BSA, which supports the strong binding of Cf with BSA.
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- 2019
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21. Stripping Voltammetric Determination of Uranium in Water Samples Using Hg-Thin Film Modified Multiwall Carbon Nanotube Incorporated Carbon Paste Electrode
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Srikant Sahoo, A. V. R. Reddy, and Ashis K. Satpati
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Materials science ,Working electrode ,Analytical chemistry ,Carbon nanotube ,Electrochemistry ,law.invention ,Carbon paste electrode ,Psychiatry and Mental health ,Adsorption ,Chemical engineering ,law ,Cathodic stripping voltammetry ,Thin film ,Voltammetry - Abstract
The variables affecting determination of ultra trace levels of uranium (VI) in aqueous samples by differential pulse cathodic stripping voltammetry were examined in detail using Hg-thin film modified carbon paste and multiwall carbon nanotube (MWCNT) incorporated carbon paste electrode. Carbon paste electrode prepared in the laboratory was modified with Hg thin film and used as the working electrode. MWCNT was incorporated into the carbon paste for enhancement in sensitivity of the measurements. Electrochemical response for the uranium (VI) reduction peak was found to be well resolved on the thin mercury film modified carbon paste surface and also with the MWCNT modification. Characteristics of the adsorption preconcentration process were investigated using electrochemical impedance measurements. Electrochemical signals were observed to be enhanced on MWCNT modification of the carbon paste.
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- 2013
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22. Voltammetric Determination of Trace Levels of Hg in Ayurvedic Medicine and in Cobalt-Containing Samples Using a Carbon Paste Electrode
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A. V. R. Reddy, Srikant Sahoo, and Ashis K. Satpati
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Detection limit ,Electrode material ,Ayurvedic medicine ,Analytical chemistry ,chemistry.chemical_element ,Cobalt ,Electrochemical Techniques ,Mercury ,Hydrogen-Ion Concentration ,Cobalt Sulfate ,Carbon ,Medicine, Ayurvedic ,Analytical Chemistry ,Carbon paste electrode ,Mercury (element) ,chemistry ,Limit of Detection ,Saturated calomel electrode ,Potentiometry ,Drug Contamination ,Electrodes ,Nuclear chemistry - Abstract
An analytical method has been described for the determination of mercury using a carbon paste electrode. Conditions for the preparation of the carbon paste electrode were optimized for low background current in order to use it for the determination of ultra trace levels of mercury. The carbon paste electrode was found to be a good electrode material for the determination of mercury. The optimized pH for the determination was in the range of 2.5 to 3.5. The three sigma detection limit of mercury was obtained as 0.095 µg L(-1). Method has been modified for determination of mercury in cobalt sulfate samples.
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- 2010
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23. Stripping Voltammetric Determination of Uranium Traces in Sea Water Samples: Effect of Surfactants on the Measurements
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Srikant Sahoo, P. V. Ravindran, G. Venkateswaran, and Ashis K. Satpati
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Aqueous solution ,Stripping (chemistry) ,Chemistry ,Biochemistry (medical) ,Clinical Biochemistry ,Inorganic chemistry ,technology, industry, and agriculture ,Analytical chemistry ,Langmuir adsorption model ,chemistry.chemical_element ,Uranium ,Biochemistry ,Analytical Chemistry ,Dielectric spectroscopy ,symbols.namesake ,chemistry.chemical_compound ,Adsorption ,Chloranilic acid ,Cathodic stripping voltammetry ,Electrochemistry ,symbols ,Spectroscopy - Abstract
The variables affecting determination of ultra trace levels of uranium (VI) in aqueous samples by differential pulse cathodic stripping voltammetry using chloranilic acid as the complexing agent have been examined in detail. Effect of organic surfactants on the voltammetric behavior has been studied. Electrochemical impedance measurements reveal the effect of adsorption of different surfactants on the adsorption pre-concentration step of uranium-chloranilic acid complex. Additionally, to better understand the analytical feature of the method, physicochemical aspects of the preconcentration process has been studied. Adsorption of uranium-chloranilic acid complex follows the Langmuir adsorption isotherm. Analysis results on sea water samples from India are reported.
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- 2010
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24. Electrochemically deposited gold nanoparticles on a carbon paste electrode surface for the determination of mercury
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Ashis K. Satpati, Srikant Sahoo, and A. V. R. Reddy
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Pharmacology ,Working electrode ,Materials science ,Inorganic chemistry ,Nanoparticle ,Metal Nanoparticles ,Electrochemical Techniques ,Mercury ,Carbon ,Analytical Chemistry ,Carbon paste electrode ,Anodic stripping voltammetry ,Colloidal gold ,Saturated calomel electrode ,Electrode ,Microscopy, Electron, Scanning ,Environmental Chemistry ,Gold ,Cyclic voltammetry ,Agronomy and Crop Science ,Electrodes ,Food Science - Abstract
An electrochemical method was developed for the determination of Hg at ultratrace levels using an Au nanoparticle (AuNP) array modified carbon paste electrode (CPE) by anodic stripping voltammetry. Scanning electron microscopy measurements imaged the size and shape of AuNPs on the CPE substrate; it was possible to tune the size and the NP density by changing the deposition time and medium. Electrochemical characterization of the AuNP modified CPE was carried out using cyclic voltammetry and electrochemical impedance measurements. Interferences due to some commonly occurring metal ions and surfactants on the stripping peak of Hg were also investigated. The 3σ detection limit for Hg using the AuNP modified electrode was as 0.24 μg/L. This method was applied to determine Hg in soil samples.
- Published
- 2015
25. Solvothermal synthesis of reduced graphene oxide/Au nanocomposite-modified electrode for the determination of inorganic mercury and electrochemical oxidation of toxic phenolic compounds
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Ashis K. Satpati, Srikant Sahoo, Dhirendra Bahadur, and Prasanta Kumar Sahoo
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Rgo/Au Nanocomposite ,Materials science ,General Chemical Engineering ,Inorganic chemistry ,Solvothermal synthesis ,Oxide ,Graphite oxide ,Catalytic-Reduction ,law.invention ,chemistry.chemical_compound ,X-ray photoelectron spectroscopy ,law ,Chronoamperometry ,Electrochemistry ,Gold Nanoparticles ,Fourier transform infrared spectroscopy ,Nanocomposite ,Graphene ,Heavy-Metals ,Graphite Oxide ,Pmp ,Mercury (Ii) ,Anodic stripping voltammetry ,chemistry ,4-Nitrophenol ,Stripping Voltammetric Determination ,Oxygen Reduction ,Stripping Voltammetry ,Glassy-Carbon Electrode ,Atomic Emission-Spectrometry ,Nuclear chemistry ,Sensing Platform - Abstract
A facile, one-step solvothermal approach has been utilized for the synthesis of a reduced graphene oxide/Au nanocomposite (RGO/Au) material. Deposition of Au nanoparticles (AuNPs) on the surface of reduced graphene oxide sheets has been realized by a simple reduction of Au precursors and graphite oxide (GO) in ethylene glycol (EG), without using any additional reductants and surfactants. The morphology of the RGO/Au nanocomposite was thoroughly examined by X-ray diffraction (XRD), Fourier transform infrared (FIR) spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and high-resolution transmission electron microscopy (HRTEM). The morphology of the RGO/Au nanocomposite was characterized by HRTEM and 20 nm was the average size of the AuNPs obtained. The performance of the RGO/Au nanocomposite has been investigated in the application of the Hg determination at the trace/ultra trace level using differential pulse anodic stripping voltammetry. The composite material was also applied for the determination of p-methoxy phenol (PMP) and, most importantly, it was observed that the material was suitable for the decomposition of PMP by the electrochemical oxidation process. The three sigma detection limits for Hg2+ and PMP were obtained as 0.25 mu gL(-1) and 0.64 mu M, respectively. The applicability of the RGO/Au nanocomposite was further extended to determine Hg soil samples. Chronoamperometric tests were carried out to investigate the performance of modified and unmodified electrodes in the decomposition of PMP by the electrochemical oxidation route. (C) 2015 Elsevier Ltd. All rights reserved.
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- 2015
26. Modification of gold electrode by self-assembled 2-mercapto benzothiazole for the determination of Hg2+
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Ashis K. Satpati, A. V. R. Reddy, and Srikant Sahoo
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Detection limit ,Open-circuit voltage ,Health, Toxicology and Mutagenesis ,Public Health, Environmental and Occupational Health ,Analytical chemistry ,Soil Science ,chemistry.chemical_element ,Electrochemistry ,Pollution ,Analytical Chemistry ,Mercury (element) ,Dielectric spectroscopy ,chemistry.chemical_compound ,chemistry ,Benzothiazole ,Electrode ,Monolayer ,Environmental Chemistry ,Waste Management and Disposal ,Water Science and Technology ,Nuclear chemistry - Abstract
An electrochemical method was developed for the determination of mercury using polycrystalline gold electrode modified by self-assembled monolayers (SAMs) of 2-mercaptobenzothiazole (MBTH). Morphological and electrochemical characterisation of the self-assembled structure of MBTH was performed using atomic force microscopy (AFM) and electrochemical impedance spectroscopy (EIS) measurements. The monolayer of MBTH has shown high affinity for Hg2+. The limit of detection for the determination of Hg2+ using the MBTH SAMs modified gold electrode was obtained as 0.421 μg L−1. The pre-concentration of Hg2+ at open circuit potential is beneficial for the onsite monitoring of mercury concentration in water samples.
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- 2014
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27. Modification of gold electrode by self-assembled 2-mercapto benzothiazole for the determination of Hg2+
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Srikant Sahoo, Ashis Kumar Satpati, Annareddy Venkata Ramana Reddy, Srikant Sahoo, Ashis Kumar Satpati, and Annareddy Venkata Ramana Reddy
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- 2015
- Full Text
- View/download PDF
28. Modification of gold electrode by self-assembled 2-mercapto benzothiazole for the determination of Hg2+
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Srikant Sahoo, Ashis Kumar Satpati, Annareddy Venkata Ramana Reddy, Srikant Sahoo, Ashis Kumar Satpati, and Annareddy Venkata Ramana Reddy
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- 2014
- Full Text
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29. Electrochemical and spectroelectrochemical investigations of quercetin on unmodified and DNA-modified carbon paste electrode and its determination using voltammetry
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Milan Kumar Dey, A. V. R. Reddy, T. Mukherjee, Srikant Sahoo, and Ashis K. Satpati
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Tafel equation ,Aqueous solution ,Chemistry ,General Chemical Engineering ,Intercalation (chemistry) ,Inorganic chemistry ,General Engineering ,Exchange current density ,Electrochemistry ,Analytical Chemistry ,Carbon paste electrode ,Electrode ,heterocyclic compounds ,Voltammetry - Abstract
The electrochemistry of quercetin on a carbon paste electrode in non aqueous and aqueous media has been investigated. Cyclic voltammetric experiments were carried out and the basic electrochemical parameters such as diffusion coefficient, exchange current density and the anodic Tafel slopes were determined. A differential pulse voltammetric procedure was proposed for the determination of quercetin in aqueous solution using a carbon paste electrode, and the detection limit was obtained as 38.5 nM L−1. The electrochemical properties of quercetin were studied using a DNA-modified carbon paste electrode using electrochemical impedance measurements. From spectroelectrochemical measurements it was evident that the hydroxyl groups at the 3′ and 4′ positions were oxidized in the presence of Cu(II) and are responsible for DNA damage. Impedance measurements supported the intercalation of quercetin into the DNA strands.
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- 2011
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30. Bi-Film on a carbon paste electrode modified with nafion film embedded with multiwall carbon nano tubes for the determination of heavy metals
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Ashis K. Satpati, A. V. R. Reddy, Milan Kumar Dey, R. Kameswaran, Srikant Sahoo, and T. Mukherjee
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Materials science ,Working electrode ,General Chemical Engineering ,Inorganic chemistry ,General Engineering ,chemistry.chemical_element ,Analytical Chemistry ,Carbon paste electrode ,chemistry.chemical_compound ,Anodic stripping voltammetry ,chemistry ,Nafion ,Electrode ,Deposition (chemistry) ,Carbon ,Voltammetry - Abstract
Bi-film was deposited on the carbon paste electrode and used as the modified electrode in stripping voltammetry. Bi deposition was carried out ex-situ in acetate buffer solution of pH 4.5 under mild stirring conditions. The deposition potential, deposition time and the Bi-concentration in the deposition solution were optimized and the corresponding values are −0.8 V (SCE), 300 s and 0.3 mM Bi-nitrate solution respectively. A substantial enhancement of an order of magnitude in the sensitivity has been observed when carbon paste electrode was modified with nafion coated carbon nano tube on which Bi-film was deposited. This enhanced sensitivity was attributed to the increased active surface area and also the enhanced charge transfer processes which increased the deposition processes and so the stripping current. Effect of different surfactants on the stripping peak of the heavy metal ions is investigated with and without modification by nafion. Detection limits using Bi-film electrode was obtained for Zn, Cd and Pb as 17.3, 16.9, 11.9 μg L−1, respectively, using Bi-film electrode. Analysis result of two water samples and two ayurvedic medicines are reported.
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- 2011
- Full Text
- View/download PDF
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