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A new sensitive sensor for simultaneous differential pulse voltammetric determination of codeine and acetaminophen using a hydroquinone derivative and multiwall carbon nanotubes carbon paste electrode.

Garazhian E, Shishehbore MR - Int J Anal Chem (2015)

Bottom Line: Electron transfer coefficient, α, catalytic electron rate constant, k, and the exchange current density, j 0, for oxidation of codeine at the HTP-MWCNT-CPE were calculated using cyclic voltammetry.The calibration curve was linear over the range 0.2-844.7 μM with two linear segments, and the detection limit of 0.063 μM of codeine was obtained using differential pulse voltammetry.The modified electrode was separated codeine and acetaminophen signals by differential pulse voltammetry.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry, Yazd Branch, Islamic Azad University, P.O. Box 89195-155, Yazd, Iran.

ABSTRACT
A new sensitive sensor was fabricated for simultaneous determination of codeine and acetaminophen based on 4-hydroxy-2-(triphenylphosphonio)phenolate (HTP) and multiwall carbon nanotubes paste electrode at trace levels. The sensitivity of codeine determination was deeply affected by spiking multiwall carbon nanotubes and a modifier in carbon paste. Electron transfer coefficient, α, catalytic electron rate constant, k, and the exchange current density, j 0, for oxidation of codeine at the HTP-MWCNT-CPE were calculated using cyclic voltammetry. The calibration curve was linear over the range 0.2-844.7 μM with two linear segments, and the detection limit of 0.063 μM of codeine was obtained using differential pulse voltammetry. The modified electrode was separated codeine and acetaminophen signals by differential pulse voltammetry. The modified electrode was applied for the determination of codeine and acetaminophen in biological and pharmaceutical samples with satisfactory results.

No MeSH data available.


Cyclic voltammograms of (a) CPE, (c) MWCNT-CPE, (e) HTP-CPE and (g) HTP-MWCNT-CPE in a 0.15 M phosphate buffer solution (pH 7.0). (b) as (a), (d) as (c), (f) as (e) and (h) as (g) in presence of 0.11 mM of codeine. Scan rate: 25 mV s−1.
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fig1: Cyclic voltammograms of (a) CPE, (c) MWCNT-CPE, (e) HTP-CPE and (g) HTP-MWCNT-CPE in a 0.15 M phosphate buffer solution (pH 7.0). (b) as (a), (d) as (c), (f) as (e) and (h) as (g) in presence of 0.11 mM of codeine. Scan rate: 25 mV s−1.

Mentions: The activity of MWCNT and HTP as a modifier and the potential of electrocatalytic oxidation of codeine at the surface of different modified electrodes including MWCNT-CPE, HTP-CPE, and HTP-MWCNT-CPE was investigated by recording the cyclic voltammograms in the absence and presence of 0.11 mM of codeine solution and comparison of them with the same voltammograms was recorded at the CPE. The electrocatalytic activity is discussed in detail as follows: voltammograms of (a) and (b) of Figure 1 show the cyclic voltammograms of CPE in the absence and presence of codeine, respectively. Similarly, the cyclic voltammograms of MWCNT-CPE are recorded in the absence (voltammogram (c)) and presence (voltammogram (d)) of 0.11 mM of codeine. A comparison of the cyclic voltammograms of CPE (Figure 1, voltammograms (a) and (b)) and MWCNT-CPE (Figure 1 voltammograms (c) and (d)) in a 0.15 M phosphate buffer solution (pH 7.0) at the scan rate of 25 mV s−1 demonstrates the efficiency of MWCNT for codeine oxidation. As it can be seen, codeine oxidation at the MWCNT-CPE was performed at potential about 550 mV with anodic peak current 0.205 μA. However, no anodic peak current was observed in other cases. Therefore, MWCNT can improve the sensitivity of the CPE for electrocatalytic oxidation of codeine.


A new sensitive sensor for simultaneous differential pulse voltammetric determination of codeine and acetaminophen using a hydroquinone derivative and multiwall carbon nanotubes carbon paste electrode.

Garazhian E, Shishehbore MR - Int J Anal Chem (2015)

Cyclic voltammograms of (a) CPE, (c) MWCNT-CPE, (e) HTP-CPE and (g) HTP-MWCNT-CPE in a 0.15 M phosphate buffer solution (pH 7.0). (b) as (a), (d) as (c), (f) as (e) and (h) as (g) in presence of 0.11 mM of codeine. Scan rate: 25 mV s−1.
© Copyright Policy - open-access
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4402475&req=5

fig1: Cyclic voltammograms of (a) CPE, (c) MWCNT-CPE, (e) HTP-CPE and (g) HTP-MWCNT-CPE in a 0.15 M phosphate buffer solution (pH 7.0). (b) as (a), (d) as (c), (f) as (e) and (h) as (g) in presence of 0.11 mM of codeine. Scan rate: 25 mV s−1.
Mentions: The activity of MWCNT and HTP as a modifier and the potential of electrocatalytic oxidation of codeine at the surface of different modified electrodes including MWCNT-CPE, HTP-CPE, and HTP-MWCNT-CPE was investigated by recording the cyclic voltammograms in the absence and presence of 0.11 mM of codeine solution and comparison of them with the same voltammograms was recorded at the CPE. The electrocatalytic activity is discussed in detail as follows: voltammograms of (a) and (b) of Figure 1 show the cyclic voltammograms of CPE in the absence and presence of codeine, respectively. Similarly, the cyclic voltammograms of MWCNT-CPE are recorded in the absence (voltammogram (c)) and presence (voltammogram (d)) of 0.11 mM of codeine. A comparison of the cyclic voltammograms of CPE (Figure 1, voltammograms (a) and (b)) and MWCNT-CPE (Figure 1 voltammograms (c) and (d)) in a 0.15 M phosphate buffer solution (pH 7.0) at the scan rate of 25 mV s−1 demonstrates the efficiency of MWCNT for codeine oxidation. As it can be seen, codeine oxidation at the MWCNT-CPE was performed at potential about 550 mV with anodic peak current 0.205 μA. However, no anodic peak current was observed in other cases. Therefore, MWCNT can improve the sensitivity of the CPE for electrocatalytic oxidation of codeine.

Bottom Line: Electron transfer coefficient, α, catalytic electron rate constant, k, and the exchange current density, j 0, for oxidation of codeine at the HTP-MWCNT-CPE were calculated using cyclic voltammetry.The calibration curve was linear over the range 0.2-844.7 μM with two linear segments, and the detection limit of 0.063 μM of codeine was obtained using differential pulse voltammetry.The modified electrode was separated codeine and acetaminophen signals by differential pulse voltammetry.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry, Yazd Branch, Islamic Azad University, P.O. Box 89195-155, Yazd, Iran.

ABSTRACT
A new sensitive sensor was fabricated for simultaneous determination of codeine and acetaminophen based on 4-hydroxy-2-(triphenylphosphonio)phenolate (HTP) and multiwall carbon nanotubes paste electrode at trace levels. The sensitivity of codeine determination was deeply affected by spiking multiwall carbon nanotubes and a modifier in carbon paste. Electron transfer coefficient, α, catalytic electron rate constant, k, and the exchange current density, j 0, for oxidation of codeine at the HTP-MWCNT-CPE were calculated using cyclic voltammetry. The calibration curve was linear over the range 0.2-844.7 μM with two linear segments, and the detection limit of 0.063 μM of codeine was obtained using differential pulse voltammetry. The modified electrode was separated codeine and acetaminophen signals by differential pulse voltammetry. The modified electrode was applied for the determination of codeine and acetaminophen in biological and pharmaceutical samples with satisfactory results.

No MeSH data available.