Preparation of Porphyrin-Based COF functionalized silica-based material as an efficient Solid-Phase Extraction adsorbent for Enrichment and Separation of Bisphenol Contaminants

Abstract

Bisphenols exert diverse effects on multiple human systems, including the reproductive, immune, and nervous systems, and are recognized as a class of endocrine-disrupting chemicals. Bisphenols are also widely present in the environment media. Therefore, developing rapid and sensitive methods for monitoring trace levels of bisphenols in environmental samples is of considerable importance. In this study, we synthesized a solid-phase extraction (SPE) material named COF-DhaTph@SiO2 via a one-pot method. This material features a silica core and a shell composed of a porphyrin-based covalent organic framework (COF). This synthesized material was subsequently employed for the separation and enrichment of three bisphenols (bisphenol A, bisphenol F, and bisphenol S) in real samples. The determined maximum adsorption capacities were 275.73 mg/g for BPA, 252.38 mg/g for BPF, and 122.36 mg/g for BPS. This enhanced adsorption performance can be attributed to the synergistic effects of multiple hydrogen bonding between the composite and the bisphenol molecules, coupled with π-π stacking interactions provided by the extended π-system of the porphyrin units within the framework. In addition, key adsorption conditions, including adsorption time, adsorption temperature, initial pollutant concentration, and solution pH, were systematically investigated and optimized. Under the optimal adsorption conditions, the limit of detection (LOD) ranged from 0.140 to 1.010μg/mL, and the limits of quantitation (LOQ) from 0.424 to 3.061μg/mL. The recovery rates for the spiked samples were 89.33% to97.33%. After five consecutive adsorption-desorption cycles, the material retained over 85% of its initial adsorption capacity, demonstrating its suitability for the enrichment of the three target bisphenols in complex samples sample matrices.