Nanozyme catalysis-powered portable mini-drainage device enables real-time and universal weighing analysis of silver...

We introduce a real-time quantitative analytical method for universal silver ions (Ag(I)) and silver nanoparticles (AgNPs) analysis based on a portable nanozyme catalysis-powered portable mini-drainage device. The device is composed of three main glass containers with different specifications. The catalase mimic of ascorbic acid-coated platinum nanoparticles (AA-PtNPs) was used to provide the pumping power to drain water by catalyzing a gas-generation reaction, and the inhibition effect of Ag(I) on the catalytic activity of AA-PtNPs is adopted to connect the target detection event with the mini-drainage device. Experimental results reveal that the mass of the overflowed water is inversely proportional to the concentration of Ag(I) and AgNPs so that their quantitation can be accomplished via real-time weighing of the overflowed water. The importance is that without requiring advanced instruments, this device can quantify Ag(I) and AgNPs with a limit of detection (LOD) of 2.0 nM for Ag(I), and 3.8 pM for AgNPs within 30 min, respectively. The reliability and accuracy are comparable with the inductively coupled plasma optical emission spectrometer (ICP-OES). All these appealing features provide us a remarkable insight into the design of versatile portable devices with potential applications in in-situ environmental monitoring under remote areas and resource-limited settings.