Ndamanisha Jean Chrysostome, Guo Liping
Faculty of Chemistry, Northeast Normal University, Changchun 130024, People's Republic of China.
Biosens Bioelectron. 2008 Jun 15;23(11):1680-5. doi: 10.1016/j.bios.2008.01.026. Epub 2008 Feb 7.
Ordered mesoporous carbon (OMC) functionalized with ferrocenecarboxylic acid (Fc) was used to modify the glassy carbon (GC) electrode. The characterization of OMC-Fc shows that, after anchoring ferrocene on the mesoporous, ordered mesostructure of the material (OMC-Fc) remains intact and Fc is electrochemically accessible. The obtained OMC-Fc-modified electrode was used to investigate the electrochemical behavior of uric acid (UA). UA oxidation is catalyzed by this electrode in aqueous buffer solution (pH 7.3) with a decrease of 200mV in overpotential compared to GC electrode. The detection and determination of UA in the presence of ascorbic acid (AA), the main interferent, were achieved. The voltammetric signals due to UA and AA were well separated with a potential difference of 308mV, a separation that can allow the simultaneous determination of UA and AA. With amperometric method, at a constant potential of 375mV, the catalytic current of UA versus its concentration shows a good linearity in the range 60-390microM (R=0.998) with a detection limit of 1.8microM (S/N=3). These results are not influenced by the presence of AA in the sample solution. With good stability and reproducibility, the present OMC-Fc-modified electrode was applied in the determination of UA content in urine sample and satisfactory results were obtained.
用二茂铁羧酸（Fc）功能化的有序介孔碳（OMC）用于修饰玻碳（GC）电极。OMC-Fc的表征表明，在将二茂铁锚定在介孔上后，材料（OMC-Fc）的有序介观结构保持完整，且Fc在电化学上可及。所得的OMC-Fc修饰电极用于研究尿酸（UA）的电化学行为。在pH 7.3的水性缓冲溶液中，该电极催化UA氧化，与GC电极相比，过电位降低了200mV。实现了在主要干扰物抗坏血酸（AA）存在下对UA的检测和测定。UA和AA产生的伏安信号以308mV的电位差得到很好的分离，这种分离能够实现UA和AA的同时测定。采用安培法，在375mV的恒定电位下，UA的催化电流与其浓度在60 - 390微摩尔范围内呈现良好的线性关系（R = 0.998），检测限为1.8微摩尔（S/N = 3）。这些结果不受样品溶液中AA存在的影响。由于具有良好的稳定性和重现性，当前的OMC-Fc修饰电极被应用于尿液样品中UA含量的测定，并获得了满意的结果。
