Cellulose Spacer Strategy: Anti-Aggregation-Caused Quenching Membrane for Mercury Ion Detection and Removal

A membrane decorated with fluorescent dyes has a great potential in detection and removal of contaminant from wastewater. However, traditional fluorescent dyes suffer from the aggregation-caused quenching effect, which could compromise their sensing efficiency. Here, a new cellulose spacer strategy is developed to conquer this challenge. Specifically, the nanocellulose has a hydrogen bond interaction with hydroxyl-containing coumarin, which serves as a spacer that prevented the pi-pi stacking of coumarin. In such a manner, a fluorescent cellulose membrane with anti-aggregation-caused quenching is obtained. As a demonstration of as-developed materials, the fluorescent cellulose membrane is used for mercury ion recognition and removal, and the membrane shows great sensing and adsorption performance. Moreover, excellent cytocompatibility of the membrane is verified by cell proliferation of live/dead viability assays. This fabrication method is expected to provide a new concept for the construction of fluorescent and biocompatible membranes for a large variety of relevant applications.