An Electrochemical Sensor for Quantitation of the Oral Health Care Agent Chlorogenic Acid Based on Bimetallic Nanowires with Functionalized Reduced Graphene Oxide Nanohybrids.

Chlorogenic acid (CGA), a phenolic acid from coffee, has been regarded as a powerful ingredient against oxidative stress and inflammation. Meanwhile, its healing feature to interfere with periodontal disease (PD) makes it a promising drug candidate. However, the existing methods for chlorogenic acid detection limit its practical application in purification and further pharmacological study in stomatology due to their lack of accuracy and productivity. Therefore, it is crucial to find a forceful approach to precisely evaluate CGA for an in-depth anti-PD study. In this work, we reported a facile and controllable synthesis of Pt@Pd nanowires (NWs) in a non-compacted core-shell structure with high electrocatalytic activity. In addition, polyethylenimine (PEI)-capped reduced graphene oxide (rGO) nanoflakes provided large binding sites for a network structure composed of interweaved Pt@Pd nanowires and protected hemin from self-destruction, which empowered Pt@Pd NWs-Hemin-PEI-rGO nanohybrids to own a large electroactive surface area and great electrochemical property for CGA detection. The enzyme-free electrochemical sensor based on Pt@Pd NWs-Hemin-PEI-rGO displayed a favorable capacity for trace CGA detection with a detection limit of 7.8 nM and a wide linear range of 0.5 μM to 4 mM. The exceptional sensitivity and selectivity of the sensor made it accomplish the measurements of chlorogenic acid in soft drinks and coffee with high consistency of HPLC results. The satisfactory performance of the obtained sensor enables it to be used for quality control and study of drug metabolism in PD treatments.