- P-ISSN 1225-0163
- E-ISSN 2288-8985
A carbon paste electrode were chemically modified using <TEX>${\alpha}$</TEX>-cyclodextrin. Characteristics of chemically modified carbon paste electrodes were studied on the basis of the inclusion complex formation of <TEX>${\alpha}$</TEX>-cyclodextrin and p-nitrophenol in solution. Cyclic voltammetry and differential pulse voltammetry were used to monitor the efficiency of the chemical modification. When the <TEX>${\alpha}$</TEX>-cyclodextrin and carbon powder ratio of 2 : 1 in weight were used, the reduction peak current of p-nitrophenol was decreased almost completely, whereas those of o-nitrophenol and hydroquinone were not changed much. This result is due to the large difference in the inclusion complex formation constants of p-nitrophenol and the other probes with <TEX>${\alpha}$</TEX>-cyclodextrin. Taking advantage of this difference, we can determine the concentration of o-nitrophenol even in the presence of p-nitrophenol.