Host–Guest-Driven Sandwich-Like Cyclodextrin Membrane for Instantaneous Diuretics Adsorption in Wastewater

The widespread presence of diuretics in wastewater, driven by their growing use in managing hypertension, heart failure, and kidney disorders as well as their chemical stability and bioactivity, poses significant environmental risks. To address these limitations, we developed a host–guest interaction-driven sandwich-like nanocomposite membrane with alternating porous and fibrous layers for rapid diuretic removal. The HPβCD composite membrane (HPβCD CM) demonstrated stable adsorption performance under acid and alkaline conditions. Within 60 s, the HPβCD CM achieved >70% removal of hydrochlorothiazide, exhibiting an adsorption rate constant 2–3 times higher than those of GAC and single-component β-cyclodextrin polymers. The maximum adsorption capacities of the membrane reached 300 mg/g for HCTZ and 200 mg/g for bendroflumethiazide and indapamide. With its outstanding adsorption performance, cost-effectiveness, and ease of regeneration, the HPβCD CM represents a promising solution for advanced water treatment applications.