Rapid and simple colorimetric detection of hydrogen sulfide using an etching-resistant effect on silver nanoprisms

A fast and sensitive colorimetric paper sensor has been developed using silver nanoprisms (Ag NPRs) with an edge length of ~50 nm for the detection of free H₂S gas. We prepared two types of Ag NPRs-coated H₂S sensing papers: a multi-zone patterned paper for passive (diffusion mode), and a single-zone patterned paper for pumped mode of H₂S gas. The change in color intensity was quantitatively analyzed of Ag NPRs-coated paper after KCl treatment depending on the concentration of H₂S gas, from yellow to purplish brown. As a result, Ag NPRs-coated H₂S sensing paper showed good sensitivity with a linear range of 1.03 to 32.9 μM H₂S, high selectivity, and good reproducibility and stability, together with a fast response time of 1 min. The developed H₂S sensing paper was applied to detect the free H₂S gas released from three types of garlic including crushed, peeled, and fresh garlic. Therefore, it can be utilized as a simple, fast, and reliable tool for on-site colorimetric detection of free H₂S gas for quality control of dietary supplements and exhaled breath analysis.Graphical abstract.