Abstract
Pyrroloquinoline quinone (PQQ) is the cofactor of many alcohol or sugar oxidising enzymes. Because of its fast redox kinetics, it can also be used as a mediator for less reactive biomolecules. It is then vital to study the electrochemistry of PQQ to understand how these enzymes and molecules work. However, PQQ does not react readily on metal or carbon electrodes and surface modification is usually required [1,2]. In this study, we present a simple way of immobilizing PQQ on carbon nanotubes.
Few-walled carbon nanotubes (FWCNT, diameter 10 nm) were drop-casted on a glassy carbon electrode. Then the electrode was dipped in PQQ solution corresponding to the studied pH. After dipping, the electrochemical response of the electrode was studied by cyclic voltammetry (CV). The results at different pH values are presented in Figure 1. The response is strong and reversible over a wide pH range compared to some other techniques [3]. Different immobilization substrates were also compared and the dependency of the response to sweep rate was studied.
Figure 1. CVs measured from the PQQ-FWCNT electrodes at pH 2-10 (at 20 mV/s).
1 H.Shinonira, G.F.Khan, Y.Ikariyama, M.Aizawa, J Electroanal Chem 304 (1991) 75
2 E.Gatz, D.D.Schlereth, H.-L.Schmidt, J Electroanal Chem 367 (1994) 59
3 H.-J.Jao, P.-Y.Tsai, C.M.Wang, J Electroanal Chem 606 (2007) 141
Few-walled carbon nanotubes (FWCNT, diameter 10 nm) were drop-casted on a glassy carbon electrode. Then the electrode was dipped in PQQ solution corresponding to the studied pH. After dipping, the electrochemical response of the electrode was studied by cyclic voltammetry (CV). The results at different pH values are presented in Figure 1. The response is strong and reversible over a wide pH range compared to some other techniques [3]. Different immobilization substrates were also compared and the dependency of the response to sweep rate was studied.
Figure 1. CVs measured from the PQQ-FWCNT electrodes at pH 2-10 (at 20 mV/s).
1 H.Shinonira, G.F.Khan, Y.Ikariyama, M.Aizawa, J Electroanal Chem 304 (1991) 75
2 E.Gatz, D.D.Schlereth, H.-L.Schmidt, J Electroanal Chem 367 (1994) 59
3 H.-J.Jao, P.-Y.Tsai, C.M.Wang, J Electroanal Chem 606 (2007) 141
| Original language | English |
|---|---|
| Title of host publication | 61st Annual Meeting of the International Society of Electrochemistry, 26.9.-1.10.2010, Nice, France |
| Publication status | Published - 2010 |
| MoE publication type | D3 Professional conference proceedings |