Preparation and Adsorption Properties of Magnetic Molecularly Imprinted Polymers for Selective Recognition of 17β-Estradiol

Abstract

In this paper, magnetic molecularly imprinted polymers (MMIPs) were fabricated on the surface of Fe3O4 by surface molecular imprinting technology, which can selectively adsorb 17β-estradiol (E2). The optimized experiments demonstrated that MMIPs possessed the best adsorption capacity when methanol was used as the solvent and MAA was used as the crosslinking agent, with a molar ratio of E2: MMA: EGDMA as 1:4:50. SEM, FTIR, and XRD were employed to investigate the morphologies of MMIPs and the results demonstrated that the MMIPs that can selectively adsorb E2 were successfully prepared on Fe3O4 particles. The adsorption experiments showed that 92.1% of E2 was adsorbed by the MMIPs, which is higher than the magnetic non-molecularly imprinted polymers (MNIPs). The Freundlich isotherm model was more suitable to describe the adsorption process of E2 by MMIPs. Meanwhile, MMIPs had a better recognition ability for E2 and its structural analogs such as estrone and estriol. The MMIPs still had good adsorption performance after methanol regeneration five times. The prepared MMIPs had the advantages of efficient adsorption ability and high reusability, so they can be applied for selective recognition and removal of E2.

Sequestration of steroidal estrogen in aqueous samples using an adsorption mechanism: a systemic scientometric review

“…76 The adsorbent performance of SWCNTs is in a very close range with 93% reported for the adsorption of E2 using magnetic molecularly imprinted polymers fabricated on the surface of Fe 3 O 4 . 74 This mechanism is consistent with those cited in several previous adsorption studies [77][78][79][80][81] using CNTs, which considered a large specic surface area with evenly distributed hydrophobic sites for organic contaminant adsorption.…”

“…Although 68 reported PSO kinetics in their research, the thermodynamic result demonstrates that the adsorption operation was predominantly chemisorption, which somewhat agrees with the report on the adsorption of E2 using magnetic molecularly imprinted polymers 74 and 3-D covalently linked GO and rGO-methoxyl ether polyethylene glycol functionalized silica 75 but differs from 73 that claimed physisorption. Furthermore, Akpotu et al 75 empirically pointed out that the −ve Δ G ° obtained proved the spontaneity and thermodynamic propitiousness of the adsorption course, which improved with an uptick in SE temperature, while the +ve Δ H ° and Δ S ° figures obtained for the adsorbing material illustrate that the adsorption operation was endothermic and improved randomness/disorderliness between the adsorbent/adsorbate interfaces.…”

“…88,108,109,116 Table 2 provides an overview of desorption and recycling in the available studies. Various eluting reagents, such as NaOH, 18 HCl, 108 HNO 3 , 116 ethanol, 74,94,109,116 methanol, 74,91 acetic acid, 91 acetonitrile, 74,82 and acetone 74 have been used to desorb different SEs from spent adsorbing materials.…”

“…However, it was opined that increasing the temperature of the regeneration process should enhance the removal of EE2. 68,74 explored a regeneration study on the E2 loaded on Fe 3 O 4 @SiO 2 @MPS by applying different eluting solvents, such as methanol, ethanol, acetone, and acetonitrile. It was observed that the optimal removal of E2 was at best for methanol, followed by ethanol, then acetonitrile and acetone.…”