Novel Mesoporous Cetyltrimethylammonium Bromide-Modified Magnetic Nanomaterials for Trace Extraction and Analysis of...

In this study, Fe₃O₄ was used as a magnetic core, combined with the characteristics of mesoporous adsorbents, to prepare a novel magnetic mesoporous composite material named MMC. Cetyltrimethylammonium bromide (CTAB) and tetraethyl orthosilicate (TEOS) were used as functional monomers, and a simple etching method was employed. The resulting MMC was used as an effective adsorbent for the magnetic solid-phase extraction of trace residues of six bisphenol endocrine disruptors (bisphenol A, bisphenol B, bisphenol C, bisphenol F, bisphenol AF, and bisphenol AP) from environmental water and food samples. Characterization results indicated that the surface of MMC exhibited a distinct wormhole-like mesoporous structure, with the successful incorporation of CTAB functional groups and Si-OH. The crystal structure of Fe₃O₄ remained stable throughout the preparation process. Mapping analysis confirmed the uniform distribution of CTAB functional groups without aggregation and demonstrated high magnetic intensity, enabling rapid separation and collection under an external magnetic field. Extraction and elution conditions were optimized, and tests were conducted for interfering substances such as humic acid, glucose, fructose, and sucrose under optimal parameters. The results showed that recovery rates were not significantly affected. The quality evaluation of the method demonstrated good linearity, a broad linear range, low limits of detection and quantification, and satisfactory recovery rates. Blank and spiked analyses were conducted for seven real samples, including environmental water (rivers and lakes) and food samples (dairy, juice, and carbonated beverages), with satisfactory spiked recovery rates achieved. Thus, the developed analytical method enables the analysis and detection of trace residues of various bisphenol pollutants in complex matrices, such as environmental water and food samples, providing a valuable reference for trace analysis of similar contaminants in complex matrices.