A Sensor Array for the Ultrasensitive Discrimination of Heavy Metal Pollutants in Seawater. (2nd June 2022)

• Record Type: Journal Article
• Authors: Ihde, Michael H.; Tropp, Joshua; Diaz, Miguel; Shiller, Alan M.; Azoulay, Jason D.; Bonizzoni, Marco
• Is Part Of: Advanced functional materials. Volume 32:Number 33(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-06-02
• Subjects: array sensing -- conjugated polymers -- environmental sensing -- fluorescence -- metal cations -- saltwater; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.202112634
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: Metal cations are potent environmental pollutants that negatively impact human health and the environment. Despite advancements in sensor design, the simultaneous detection and discrimination of multiple heavy metals at sub‐nanomolar concentrations in complex analytical matrices remain a major technological challenge. Here, the design, synthesis, and analytical performance of three highly emissive conjugated polyelectrolytes (CPEs) functionalized with strong iminodiacetate and iminodipropionate metal chelates that operate in challenging environmental samples such as seawater are demonstrated. When coupled with array‐based sensing methods, these polymeric sensors discriminate among nine divalent metal cations (Cu II, Co II, Ni II, Mn II, Fe II, Zn II, Cd II, Hg II, and Pb II ). The unusually high and robust luminescence of these CPEs enables unprecedented sensitivity at picomolar concentrations in water. Unlike previous array‐based sensors for heavy metals using CPEs, the incorporation of distinct π‐spacer units within the polymer backbone affords more pronounced differences in each polymer's spectroscopic behavior upon interaction with each metal, ultimately producing better analytical information and improved differentiation. To demonstrate the environmental and biological utility, a simple two‐component sensing array is showcased that can differentiate nine metal cation species down to 500 × 10 −12 m in aqueous media and to 100 × 10 −9 m in seawater samples collected from the Gulf of Mexico. Abstract : Low cost and rapid methods for the detection of multiple heavy metal pollutants at environmentally relevant concentrations in complex analytical matrices remain a major technological challenge. Here, highly emissive conjugated polyelectrolytes with strong metal chelates combined in a simple two‐component sensing array enable the differentiation of nine metal cations in complex aqueous environments such as seawater with unprecedented sensitivity.