Pompon mum-like ionic covalent organic framework nanocomposites for efficient solid-phase extraction of nonsteroidal...

Molecularly imprinted ionic covalent organic framework nanocomposites (MI-IC-COF@SnO₂) were prepared as potential adsorbents for the enhanced adsorption of nonsteroidal anti-inflammatory drugs (NSAIDs) from aqueous solution. The resulting material exhibited a pompon mum-like structure, featuring a large surface area, and well-defined mesopores. The presence of uniform positive ions within the three-dimensional skeleton of MI-IC-COF@SnO₂ facilitated a rapid adsorption rate and high adsorption capacity for target analytes. Thermodynamic fitting revealed the adsorption process of NSAIDs to be feasible, endothermic, and spontaneous. Additionally, the adsorbent material exhibited respectable selectivity, as evidenced by imprinting factor values ranging from 2.8 to 6.7. Utilizing MI-IC-COF@SnO₂ as the sorbent, a solid-phase extraction method coupled with high-performance liquid chromatography-ultraviolet detection (SPE-HPLC-UV) was developed and optimized. The proposed method demonstrated good linear range with determination coefficients of 0.998-0.999, and low limit of detection (0.18-1.35 µg L^-1). Recoveries of NSAIDs in urine and river water samples were 78.1 %-106.1 %, with relative standard deviations lower than 12.5 %. This rapid and sensitive method enables the determination of NSAIDs at trace levels in complex matrices, providing reliable and reproducible results.