TY - JOUR
T1 - Amperometric detection of morphine at a Prussian blue-modified indium tin oxide electrode
AU - Ho, Kuo Chuan
AU - Chen, Chia Yi
AU - Hsu, Huan Cheng
AU - Chen, Lin Chi
AU - Shiesh, Shu Chu
AU - Lin, Xi Zhang
N1 - Funding Information:
Helpful discussions with Prof. Tse-Chuan Chou of the Department of Chemical Engineering of National Cheng Kung University, Tainan, Taiwan are greatly appreciated. We deeply appreciate the sister of Mr. Ying-Chan Hsu, a Ph.D. candidate in our lab, for supplying the codeine. This research was supported by the Program for Promoting Academic Excellence of University, sponsored by the Ministry of Education of Republic of China, under grant no. EX91-E-F-FA09-5-4.
PY - 2004/7/30
Y1 - 2004/7/30
N2 - In this work, the electrocatalytic oxidation of morphine (MO) at an optically transparent indium tin oxide (ITO) electrode modified by an electrodeposited Prussian blue (PB) thin film is first demonstrated, and the amperometric detection of MO was then investigated. Experimental results showed that the thin film on the ITO surface, confined to the PB/Berlin green (BG) redox pair, can serve as an excellent mediator which facilitates electron transfer and considerably lowers the overpotential required, as compared to a bare ITO electrode. Thus, PB can be regarded as a promising artificial peroxidase for MO. The rate of such an electrocatalytic reaction is pH dependent with the highest value at pH 5. By potential-step excitation from 0.55 to 0.70 V, a linear calibration curve, displaying the relationship between steady-state currents and MO concentrations (ranging from 0.09 to 1.0 mM), was obtained. The detection sensitivity is about 16.8 μA/cm2 mM. Most importantly, the method described herein can readily discriminate MO analogs lacking the phenolic -OH group, such as codeine, and can thus benefit the specific recognition of MO.
AB - In this work, the electrocatalytic oxidation of morphine (MO) at an optically transparent indium tin oxide (ITO) electrode modified by an electrodeposited Prussian blue (PB) thin film is first demonstrated, and the amperometric detection of MO was then investigated. Experimental results showed that the thin film on the ITO surface, confined to the PB/Berlin green (BG) redox pair, can serve as an excellent mediator which facilitates electron transfer and considerably lowers the overpotential required, as compared to a bare ITO electrode. Thus, PB can be regarded as a promising artificial peroxidase for MO. The rate of such an electrocatalytic reaction is pH dependent with the highest value at pH 5. By potential-step excitation from 0.55 to 0.70 V, a linear calibration curve, displaying the relationship between steady-state currents and MO concentrations (ranging from 0.09 to 1.0 mM), was obtained. The detection sensitivity is about 16.8 μA/cm2 mM. Most importantly, the method described herein can readily discriminate MO analogs lacking the phenolic -OH group, such as codeine, and can thus benefit the specific recognition of MO.
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U2 - 10.1016/j.bios.2003.11.027
DO - 10.1016/j.bios.2003.11.027
M3 - Article
C2 - 15142570
AN - SCOPUS:2342552469
SN - 0956-5663
VL - 20
SP - 3
EP - 8
JO - Biosensors and Bioelectronics
JF - Biosensors and Bioelectronics
IS - 1
ER -