Porphyrin-Based Photoelectrochemical Sensor for High-Sensitivity Chloramphenicol Detection Via Harmonized Interaction with Nzvi and Graphene

Abstract

The efficient combination of graphene nanoplatelets and zero-valent iron nanoparticles with porphyrin fibres forms the heterojunction. This structure demonstrates potential in modifying the working electrode surface to improve Chloramphenicol sensing performance via the photoelectrochemical method. Using Cleistocalyx Operculatus extract as a reducing agent, Fe/GNPs were synthesized, which were then combined with TCPP by self-assembly. The Fe/GNPs/TCPP structure exhibits remarkable stability and a significant synergistic effect in increasing the photoelectrochemical process. In addition, the mechanism and role of each component in the material structure in enhancing the electrochemical behaviour are proposed. Indeed, the detection concentration range of the proposed electrode is extended from 1 to 50 µM, compared to 5 to 50 µM without illumination. The limit of detection and sensitivity values ​​were also improved, respectively 0.87 µM and 0.9439 µA.µM-1.cm-2 compared to 1.77 µM and 0.6247 µA.µM-1.cm-2  without light.

Keywords: Graphene nanoplatelets, Zero-valent iron nanoparticles, photoelectrochemical sensing, porphyrin fibers, Chloramphenicol detection