From dual-mode to multi-modal electrochemical based sensors: A path toward accurate sensing

In recent years, the chemical sensing field has seen the rise of a new class of sensors that utilize more than unique transduction modes. Known as 'dual-mode' or 'bimodal' sensors, these devices integrate two distinct mechanisms within the same platform, providing separate signals to detect or quantify the same analyte. This approach offers built-in cross-validation, significantly enhancing the precision and accuracy of the sensors. These selfchecked systems have unlocked the potential of nanomaterials with versatile properties, enabling their simultaneous use across various sensing mechanisms. Electrochemical sensors, in particular, have leveraged this approach, leading to the development of dual-mode electrochemical-based sensors that pair electrochemistry with techniques such as Colorimetry, Fluorescence, Photoelectrochemistry, or even two different Electrochemical methods. The evolution of these technologies has also led to the emergence of multi-modal sensors, incorporating more than two modes within a single system. This review explores the latest advancements in multi-modal electrochemical-based sensors, examining their design strategies and highlighting recent work published in this evolving field.