Functionalized nanomaterials for detection and removal of organic pollutants

Background: Literature reveals the continuous release of pharmaceuticals and their metabolites into the environment from various sources, including urban domestic effluents, necessitating enhanced treatment methods to monitor and mitigate such contaminants in wastewater.

Results: This study presents the development of a self-assembled chemo sensor utilizing an azodye-based imine-linked Co²⁺ complex (R1.Co²⁺), demonstrating potential for ratiometric and colorimetric quantification of amoxicillin (AMX) in buffer/aqueous media with a limit of detection (LOD) of 0.717 μM and a limit of quantification (LOQ) of 4.14 μM. Additionally, electrochemical studies elucidate the mechanism of AMX detection, indicating selective oxidation of AMX by the R1.Co²⁺ complex without interference from other analytes. FE-SEM analysis reveals analyte-induced self-assembly of the probe R1.Co²⁺ upon interaction with AMX. Moreover, immobilization of the R1.Co²⁺ complex onto polyether sulfone (PES) membranes demonstrates promising potential for AMX removal from environmental wastewater, exhibiting an adsorption capacity of 450.1 mg g^–1 and removal efficiency of 90%. Furthermore, the hybrid membrane serves as a solid-state colorimetric sensor for AMX, as evidenced by the hue, saturation, and value (HSV) parameter model, validated through a portable mobile-based prototype.

Conclusion: To conclude, this work represents a novel azodye-based imine-linked Co²? complex (R1.Co²?) as a dual-function chemo sensor and adsorbent for amoxicillin (AMX) detection and removal. The probe exhibits high sensitivity (LOD: 0.717?μM) and selectivity, supported by electrochemical and FE-SEM analyses. Immobilization onto PES membranes enables efficient AMX removal (90% efficiency) and real-time solid-state colorimetric sensing. The approach is further validated using a portable, HSV-based mobile detection prototype.

Kamalpreet Kaur is currently pursuing a Ph.D. at the Indian Institute of Technology (IIT) Ropar, with a research focus on supramolecular synthesis and sensing applications. Her work primarily involves the design and development of functional molecular systems for chemical sensing and environmental remediation. She is particularly interested in exploring coordination complexes and their self-assembly behavior for advanced analytical and sensing platforms.