Confronting pressure and humidity limitations in gold nanoparticle sensors array for enhancing electronic nose technology in real-world applications

The field of disease smelling diagnosis has experienced a major breakthrough with the development of the electronic nose (E-nose) that utilizes thiol-capped gold nanoparticles (GNPs). This study focuses on overcoming the challenges of sensors to detect VOCs stably confounding with interferents of humidity and pressure, and clarifying their essential mechanism. An innovative and straightforward method for synthesizing GNPs and modifying their surface has been developed. This unique approach deviates from the conventional Brust method by completely removing any traces of tetraoctylammonium bromide (TOAB), ensuring reproducibility and simplicity of use. This modification enhances the sensor’s responsiveness to both polar and non-polar VOCs, as well as strengthen selectivity and anti-interferant capabilities. The mechanism of generating sensing cross-talk from TOAB residue is proposed through rigorous sensing experiments, X-ray photoelectron spectroscopy (XPS) results, and theoretical analysis. Thus, this study enhances the responsiveness of the sensor to both polar and non-polar VOCs, while also strengthening its selectivity and anti-interferent capabilities. This could potentially revolutionize the practical applications of E-nose in smelling diagnosis. Graphical abstract