Plasma-assisted synthesis of carbon fibers/ZnO core–shell hybrids on carbon fiber templates for detection of ascorbic acid and uric acid

Abstract

Carbon fibers/ZnO core–shell hybrids were synthesized in this study by plasma-assisted strategy using carbon fiber templates. The hybrids were characterized by scanning electron microscopy and X-ray diffraction which revealed that the ZnO hybrids were attached on the surface of the carbon nanofibers. The hybrids were used to fabricate microelectrodes, exhibiting a strong electrocatalytic activity toward oxidation of ascorbic acid (AA) and uric acid (UA). Combination of the carbon fibers and ZnO largely increased the surface area of the electrodes, enhanced electron transfer on the electrode surface and widened the distance between oxidation potential of AA and UA. The hybrids therefore endowed the microelectrodes with portability, stability, higher selectivity and sensitivity. A biosensor was thus developed for detection of AA and UA concerning the above properties. The linear range for the AA and UA were 600–2000μM and 20–200μM, respectively. This work provides a portable and green route for constructing the biomedical sensor with promising prospect for clinical diagnosis.