Now showing 1 - 4 of 4
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    A sensitive electrochemical detection of progesterone using tin-nanorods modified glassy carbon electrodes: Voltammetric and computational studies
    (01-03-2018)
    Das, Ashis
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    In recent years, there has been significant interest in the design of electrodes for enhanced electrochemical sensing platforms towards selective and sensitive detection of biological steroid hormones. We report here a facile, template-free electrodeposition of tin nanorods on glassy carbon electrodes and analyse its efficacy for the sensing of progesterone using voltammetric and amperometric techniques. The physicochemical properties of the tin-nanorods modified glassy carbon electrodes are characterized by electron microscopic studies, UV–vis spectral analysis, X-ray diffraction and electrochemical impedance spectroscopy. The mechanism involved in the reduction of progesterone has been elucidated using quantum chemical calculations and the influence of the cationic surfactant (cetyltrimethylammonium bromide) is pointed out. The estimation of progesterone is carried out with differential pulse voltammetry and amperometry. The electrode exhibits an impressive response towards the sensing of progesterone in terms of higher sensitivity, linear calibration regime varying from 40 to 600 μM with the lowest detection limit being 0.12 μM. The effect of other interfering agents such as testosterone, 17β-estradiol, creatinine, uric acid and ascorbic acid is also analysed using differential pulse voltammetry. The analysis of progesterone assay in commercial pharmaceutical formulations has also been carried out and reveals a satisfactory agreement.
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    Publication
    Electrochemical Sensing of Nitrite Ions Using Tin-Submicroparticles Modified Glassy Carbon Electrodes
    (01-11-2014)
    Sivasubramanian, R.
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    The applicability of tin submicroparticles modified glassy carbon electrodes for sensing of nitrite ions is demonstrated. Tin submicroparticles have been electrodeposited on a glassy carbon electrode using constant potential deposition. The detection of nitrite ions is carried out with differential pulse voltammetry, amperometry and electrochemical impedance spectroscopy. The lowest detection limit of 0.5μM with a linear range of 5μM-1000μM is inferred from the differential pulse voltammetry. The interference from different compounds such as urea, glucose and nitrate ions is also analyzed.
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    Publication
    Electroanalytical Sensor Based on Unmodified Screen-Printed Carbon Electrode for the Determination of Levo-Thyroxine
    (01-02-2015)
    Das, Ashis
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    The electrochemical behaviour of thyroxine (T4) is analysed using the disposable screen-printed carbon electrode (SPCE) in the neutral phosphate buffer solution with cyclic voltammetric technique. The Differential Pulse Voltammetry and Chronoamperometry were employed for sensing of T4. The lowest detection limit of 3nM was obtained from the differential pulse voltammetric method without preconditioning. The Density Functional Theoretical study of T4 was performed to elucidate the mechanism of oxidation. The analysis of the commercial pharmaceutical samples indicates the validity of the proposed method.
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    Publication
    Differential pulse voltammetry as an alternate technique for over oxidation of polymers: Application of electrochemically synthesized over oxidized poly (Alizarin Red S) modified disposable pencil graphite electrodes for simultaneous detection of hydroquinone and catechol
    (15-03-2017)
    Aravindan, N.
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    We have demonstrated the effectiveness of differential pulse voltammetry (DPV) as a technique for the preparation of an over oxidized poly (Alizarin Red S) modified disposable pencil graphite electrode (o-PARS/PGE). The modified electrodes were analyzed using spectroscopic, electron microscopic and electrochemical techniques. As an application, the o-PARS/PGE was used for the simultaneous determination of hydroquinone (HQ) and catechol (CC) using DPV and double potential pulse chronoamperometry (DPCA). It was found that o-PARS/PGE exhibited an excellent electrocatalytic activity and differentiating ability towards HQ and CC with a peak separation of 100 mV. Under the optimized conditions, the calibration curves showed linearity in the range of 0.5–600 μM for both the isomers with a limit of detection (LOD, 3σ/m) of 0.452 μM and 0.122 μM for HQ and CC respectively. The practical viability of the fabricated electrode was demonstrated by the successful determination of HQ and CC in a tap water sample with satisfactory recovery. On comparison with other commonly employed electrochemical techniques for over oxidation, o-PARS/PGE prepared using DPV was found to be more sensitive.