Edible gold leaf as a viable modification method for screen-printed sensors

Camargo, Jéssica R ORCID: https://orcid.org/0000-0003-1836-7495, Cleto, Sabrina, Neumann, Amanda, Azzi, Déborah C, Crapnell, Robert D ORCID: https://orcid.org/0000-0002-8701-3933, Banks, Craig E ORCID: https://orcid.org/0000-0002-0756-9764 and Janegitz, Bruno C (2024) Edible gold leaf as a viable modification method for screen-printed sensors. Electrochimica Acta, 478. 143825. ISSN 0013-4686

Accepted Version File will be available on: 17 January 2025. Available under License Creative Commons Attribution Non-commercial No Derivatives. Download (1MB)

Abstract

The demand for low-cost, efficient, selective, and sensitive analytical methods is increasing globally, making electroanalysis combined with screen-printed electrodes an appealing option. Gold, known for its excellent electrical conductivity and biocompatibility, improves the electrocatalytic activity of the sensors and reduces interference with other substances. Here, we propose the modification of disposable sensors with edible gold leaf, which is a cost-effective alternative to sputtering. The gold leaf was immobilized on the screen-printed electrode surface with chitosan. L-tyrosine, an amino acid, and an important biomarker for the diagnosis of various diseases was detected as a proof-of-concept. Using square-wave voltammetry for the determination of L-tyrosine, the disposable sensor modified with gold leaf showed a linear response in the range between 0.10 to 70 μmol L−1 with a limit of detection of 0.09 μmol L−1. Overall, the use of gold leaf to modify disposable electrochemical sensors for L-tyrosine detection represents a promising approach for electrochemical sensing.