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 HS gas. We prepared two types of Ag NPRs-coated HS sensing papers: a multi-zone patterned paper for passive (diffusion mode), and a single-zone patterned paper for pumped mode of HS gas. The change in color intensity was quantitatively analyzed of Ag NPRs-coated paper after KCl treatment depending on the concentration of HS gas, from yellow to purplish brown. As a result, Ag NPRs-coated HS sensing paper showed good sensitivity with a linear range of 1.03 to 32.9 μM HS, high selectivity, and good reproducibility and stability, together with a fast response time of 1 min. The developed HS sensing paper was applied to detect the free HS 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 HS gas for quality control of dietary supplements and exhaled breath analysis.Graphical abstract.