| Boronates, such as arylboronic acids, have been found broad application in electrochemical sensors. They can be transformed into phenols by hydroxylation of boronic acids, such as oxidation of hydrogen peroxide (H2O2) and catalysis of copper. Moreover, phenols are also a well recognized probe, which can be used for biosensor construction. Recently, nanomaterials have attracted extensive attentions in the field of electrochemical sensing. Carbon nanomaterials, especially, are widely applied because of their novel and unique carbon nanostructures along with a great specific surface area and better electronic properties. In this dissertation, the determination of uric acid (UA) using boronate oxidation approach was developed, and single-walled carbon nanohorns (SWCNHs) were applied in constructing ethanol biosensor. The main points are as follows:1. Herein, we report a new method for the detection of hydrogen peroxide at a low potential based on the selective oxidation of p-hydroxyphenylboronic acid by hydrogen peroxide to generate easily detectable p-hydroxyphenol. This method was further used to detect UA and uricase by coupling with enzymatic reaction. Moreover, the practicability of the biosensor was tested by determining the concentrations of UA in serum sample. The average recoveries for the determination of samples and the RSDs were achieved.2. The reaction between p-aminophenylboronic acid and enzymatically generated H2O2yields p-aminophenol immediately. The p-aminophenol served as a well recognition probe, combined with SWCNHs for indirect determination of H2O2, alcohol and alcohol oxidase. The biosensor had good stability and reproducibility. |
