TiO2 sol-gel derived amperometric biosensor for H2O2 on the electropolymerized phenazine methosulfate modified electrode.

A novel hydrogen peroxide biosensor was developed based on the immobilization of horseradish peroxidase (HRP) in a TiO(2) sol-gel matrix on an electropolymerized phenazine methosulfate (PMS) modified electrode surface. Such membranes are of interest due to their high surface area, biological compatibility, and ease of fabrication. HRP entrapped in the TiO(2) matix was stable and retained its activity to a large extent.

Differentiating the orientations of photosynthetic reaction centers on Au electrodes linked by different bifunctional reagents.

The photosynthetic reaction center (RC) composite film was fabricated by self-assembled monolayers (SAMs) on the Au electrode with two different bifunctional reagents, 4-aminothiophenol (ATP) and 2-mercaptoethylamine (MEA), respectively. The square wave voltametry (SWV), bulk electrolysis and photocurrent test were employed for characterizing the composite film. The dramatic different electrochemical characteristics were observed for the two types of films, which strongly suggested an orientational difference for RC arising from the structural difference between the two bifunctional reagents.

Determination of hesperidin and synephrine in Pericarpium Citri Reticulatae by capillary electrophoresis with electrochemical detection.

A method based on capillary electrophoresis with electrochemical detection (CE-ED) has been developed for the determination of hesperidin (HP) and synephrine (SP) in the Chinese traditional herbal drug, Pericarpium Citri Reticulatae, the dried rind of the ripe fruits of Citrus reticulata Blanco (mandarin orange). The effects of some important factors such as the acidity and concentration of running buffer, separation voltage, and detection potential were investigated to determine the optimum conditions. The working electrode was a 300 microm diameter carbon disc electrode positioned opposite the outlet of the capillary.