Electrochemically Pretreated Carbon Microfiber Electrodes as Sensitive HPLC-EC Detectors

Figure 5

Chromatogram of standard mixture of phenolic acids. Conditions: amperometric detection at 1200 mV (versus Ag/AgCl), for other conditions see Section 2; analyte concentration: 10 ng/mL each. Inset chromatogram: analysis of 1 ng/mL concentration (2.5 pg on-column each acid). Legend: 1: gallic acid, 2: protocatechuic acid, 3: gentisic acid, 4: p-hydroxybenzoic acid, and 5: caffeic acid.