A multiwalled carbon nanotubes/poly(bromocresol green) modfied glassy carbon electrode (MWNTs-PBG/GCE) was used to investigate the electrochemical behavior of reduced glutathione(GSH). GSH showed an irreversible oxida...A multiwalled carbon nanotubes/poly(bromocresol green) modfied glassy carbon electrode (MWNTs-PBG/GCE) was used to investigate the electrochemical behavior of reduced glutathione(GSH). GSH showed an irreversible oxidation process on MWNTs-PBG/GCE with an oxidation peak at 0.77 V(vs. SCE) in a phosphate buffer solution(pH=4.0). The kinetic parameters of the electrochemical behavior of GSH on MWNTs-PBG/GCE were calculated. Under the optimal conditions and with the help of amperometric method, a linear relationship was obtained between the oxidation peak current and GSH concentration in the range from 2×10-7 mol/L to 5×10-6 mol/L with the detection limit as 1×10-8 mol/L(signal-to-noise ratio of 3). The current reached the steady-state current within about 5 s. The modified electrode surface had very good reproducibility and stability.展开更多
The heavy metals determination in tap water samples using microcolumn packed with multiwalled carbon nanotubes （MWNTs） as a solid-phase extraction adsorbent before to their determination by inductively coupled plasm...The heavy metals determination in tap water samples using microcolumn packed with multiwalled carbon nanotubes （MWNTs） as a solid-phase extraction adsorbent before to their determination by inductively coupled plasma mass spectrometry （ICP-MS） has been studied. Standard addition method was applied for the calibration using aqueous solutions. The metals ions absorption were achieved by multiwalled carbon nanotubes （MWNTs） at pH 8.0, and then these retained metals on MWNTs column were eluted by 1.0 mol.L^-1 HNO3. The analytical parameters for the determination ofFe, Cu, and Zn in tap water samples which have been investigated previously were applied. Fifteen tap water samples were collected from different locations of Riyadh metropolitan area and then determined the concentration ofFe, Cu, and Zn by ICP-MS after preconcentration with MWNTs. The concentration range for Fe, Cu, and Zn measured （μg/L） in water samples are 23.37-137.91, 2.12-121.36, and 14.43-202.47 respectively. The level of Fe exceeded the limits set by WHO and SASO for drinking water.展开更多
基金Supported by the National Natural Science Foundation of China(No.20775044)the Natural Science Foundation of Shandong Province of China(No.Y2006B20)
文摘A multiwalled carbon nanotubes/poly(bromocresol green) modfied glassy carbon electrode (MWNTs-PBG/GCE) was used to investigate the electrochemical behavior of reduced glutathione(GSH). GSH showed an irreversible oxidation process on MWNTs-PBG/GCE with an oxidation peak at 0.77 V(vs. SCE) in a phosphate buffer solution(pH=4.0). The kinetic parameters of the electrochemical behavior of GSH on MWNTs-PBG/GCE were calculated. Under the optimal conditions and with the help of amperometric method, a linear relationship was obtained between the oxidation peak current and GSH concentration in the range from 2×10-7 mol/L to 5×10-6 mol/L with the detection limit as 1×10-8 mol/L(signal-to-noise ratio of 3). The current reached the steady-state current within about 5 s. The modified electrode surface had very good reproducibility and stability.
文摘The heavy metals determination in tap water samples using microcolumn packed with multiwalled carbon nanotubes （MWNTs） as a solid-phase extraction adsorbent before to their determination by inductively coupled plasma mass spectrometry （ICP-MS） has been studied. Standard addition method was applied for the calibration using aqueous solutions. The metals ions absorption were achieved by multiwalled carbon nanotubes （MWNTs） at pH 8.0, and then these retained metals on MWNTs column were eluted by 1.0 mol.L^-1 HNO3. The analytical parameters for the determination ofFe, Cu, and Zn in tap water samples which have been investigated previously were applied. Fifteen tap water samples were collected from different locations of Riyadh metropolitan area and then determined the concentration ofFe, Cu, and Zn by ICP-MS after preconcentration with MWNTs. The concentration range for Fe, Cu, and Zn measured （μg/L） in water samples are 23.37-137.91, 2.12-121.36, and 14.43-202.47 respectively. The level of Fe exceeded the limits set by WHO and SASO for drinking water.
