A novel, simple and efficient strategy for fabricating a magnetic metal-organic framework (MOF) as sorbent to remove organic compounds from simulated water samples is presented and tested for removal of methylene blue (MB) as an example. The novel adsorbents combine advantages of MOFs and magnetic nanoparticles and possess large capacity, low cost, rapid removal and easy separation of the solid phase, which makes it an excellent sorbent for treatment of wastewaters. The resulting magnetic MOFs composites (also known as MFCs) have large surface areas (79.52 m² g⁻¹), excellent magnetic response (14.89 emu g⁻¹) and large mesopore volume (0.09 cm³ g⁻¹), as well as good chemical inertness and mechanical stability. Adsorption was not drastically affected by pH, suggesting π–π stacking interaction and/or hydrophobic interactions between MB and MFCs. Kinetic parameters followed pseudo-second-order kinetics and adsorption was described by the Freundlich isotherm. Adsorption capacity was 84 mg MB g⁻¹ at an initial MB concentration of 30 mg L⁻¹, which increased to 245 mg g⁻¹ when the initial MB concentration was 300 mg L⁻¹. This capacity was much greater than most other adsorbents reported in the literature. In addition, MFC adsorbents possess excellent reusability, being effective after at least five consecutive cycles.

Legacy per- and polyfluoroalkyl substances (PFASs) have elicited much concern because of their ubiquitous distribution in the environment and the potential hazards they pose to wildlife and human health. Although an increasing number of effective PFAS alternatives are available in the market, these alternatives bring new challenges. This paper comprehensively reviews how PFASs bind to transport proteins (e.g., serum albumin, liver fatty acid transport proteins and organic acid transporters), nuclear receptors (e.g., peroxisome proliferator activated receptors, thyroid hormone receptors and reproductive hormone receptors) and membranes (e.g., cell membrane and mitochondrial membrane). Briefly, the hydrophobic fluorinated carbon chains of PFASs occupy the binding cavities of the target proteins, and the acid groups of PFASs form hydrogen bonds with amino acid residues. Various structural features of PFAS alternatives such as chlorine atom substitution, oxygen atom insertion and a branched structure, introduce variations in their chain length and hydrophobicity, which potentially change the affinity of PFAS alternatives for endogenous proteins. The toxic effects and mechanisms of action of legacy PFASs can be demonstrated and compared with their alternatives using binding models. In future studies, in vitro experiments and in silico quantitative structure-activity relationship modeling should be better integrated to allow more reliable toxicity predictions for both legacy and alternative PFASs.