Dual-Functional Nanocellulose-Based Plasmonic Membrane for Both Detection and Removal of Organic Contaminants

The existence of organic pollutants in our environment is a growing concern. Many processes (e.g., textiles, painting, and printing) release waste effluents with organic pollutants (e.g., synthetic dyes) that harm aquatic systems. However, detecting and removing them efficiently and effectively is challenging. This study addressed this by developing a dual-functional plasmonic membrane using biowaste-derived nanocellulose for both detection and removal. The plasmonic nanomaterial was integrated with surface-enhanced Raman spectroscopy (SERS) to identify and quantify three organic pollutants (basic red 9, BR9; malachite green, MG; and methylene blue, MB). The nanocellulose removed these pollutants through electrostatic attraction. The organic pollutants were detected down to 0.05 mg/L, 0.25 mg/L, and 0.05 mg/L for BR9, MG, and MB, respectively; these concentrations are well below those considered to be environmentally hazardous. SERS analysis was performed in spiked streamwater samples to demonstrate detection in an environmentally relevant matrix. The nanomaterial was also used to remove the pollutants from aqueous matrices; removal efficiencies were 99.54 +/- 0.16% for BR9, 99.50 +/- 0.25% for MG, and 99.84 +/- 0.10% for MB. For pollutant-spiked stream samples, removal efficiencies were 98.76 +/- 1.26% for BR9, 97.50 +/- 2.29% for MG, and 98.33 +/- 1.59% for MB. This study demonstrates the high potential of this nanomaterial for the simultaneous detection and removal of organic contaminants, which provides the first example of using biowaste-derived functional nanomaterial for water testing and remediation concurrently.