A dual-functional sensing platform for quantitative detection and adsorption of Congo red based on magnetic fluorescent ZIF composites

The widespread accumulation of Congo red (CR) in industrial wastewater poses severe ecological and health risks due to its carcinogenicity and environmental persistence. Exploring the detection and adsorption strategy of CR is crucial for ensuring public health and protecting the environment. In this work, a magnetic composite named MMWCNTs@CDs@ZIF-8 was developed as a dual-functional sensing platform for precise quantitative detection and efficient adsorption of CR. MMWCNTs@CDs@ZIF-8 exhibited a linear range from 0.25 to 5 μM, and demonstrated low limit of detection (17.46 nM) and rapid response (4 min). Furthermore, it exhibited superior selectivity and anti-interference performance, making it suitable for environmental water samples analysis, with satisfactory recoveries and low relative standard deviations. The underlying detection mechanism was attributed to be internal filtration effect. Additionally, the adsorption performance of MMWCNTs@CDs@ZIF-8 was explored, and the maximum adsorption capacity was 131.84 mg g −1 , which demonstrated promising potential as an effective adsorbent for CR removal. Therefore, the proposal of MMWCNTs@CDs@ZIF-8) enables dual detection-decontamination functionality, providing innovative insights into constructing a versatile dual-functional sensing platform.