Novel magnetic core-shell nanoparticles for the removal of polychlorinated biphenyls from contaminated water sources

Abstract

In this work, we developed novel core-shell nanoparticle systems with magnetic core and polymer shell via atom transfer radical polymerization for use as high affinity nanoadsorbents for organic contaminants in water and wastewater treatment. Polyphenolic-based moieties, curcumin multiacrylate (CMA) and quercetin multiacrylate (QMA), were incorporated into poly(ethylene glycol) (PEG) based polymeric shells to create high affinity binding sites for the capture of polychlorinated biphenyls (PCBs) as a model pollutant. The resulting magnetic nanoparticles (MNPs) were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), transmission electron microscopy (TEM), X-ray diffraction (XRD), dynamic light scattering (DLS), and UV-visible spectroscopy. The affinity of these novel materials for PCB 126 was evaluated and fitted to the nonlinear Langmuir model to determine binding affinities (KD). The KD values obtained were: PEG MNPs (8.42 nM) < IO MNPs (8.23nM) < QMA MNPs (5.88 nM) < CMA MNPs (2.72 nM), demonstrating that the presence of polyphenolic-based moieties enhanced PCB 126 binding affinity, which is hypothesized to be a result of ππ stacking interactions. These values are lower that KD values for activated carbon, providing strong evidence that these novel core-shell nanoparticles have a promising application as nanoadsorbents for specific organic contaminants offering a cost effective alternative to current remediation approaches.

Modulating electrospun polycaprolactone scaffold morphology and composition to alter endothelial cell proliferation and angiogenic gene response

“…Furthermore, the infiltration depth of cells could have an impact on the noted gene expression. It has been previously documented that oxygen transfer to deeper parts of a scaffold can be limited depending on the scaffold's architecture [66]. While this is unlikely in the present study, due to the highly porous nature of the scaffolds, it is worth considering in future experiments.…”

Synthesis of magnetic nanocomposite microparticles for binding of chlorinated organics in contaminated water sources

“…The PEG systems present a lower affinity for PCB 126 in the aqueous solution most likely due to the hydrophilic nature of the PEG400DMA, therefore impeding interactions with the hydrophobic PCB 126 molecules. [45] The CMA and QMA containing systems exhibit a higher binding affinity for the PCB molecule, which can be explained on the basis of the presence of π-π stacking interaction between the aromatic rings in the adsorbate and the adsorbant. This result demonstrates the important role the incorporation of the functional monomers, CMA and QMA, imparts into the microparticle systems by increasing the affinity of the material via the introduction of πelectron rich sites that allow for π-electron coupling/stacking, and lead to an overall increase in hydrophobicity.…”

“…Recently, our group developed nanoadsorbent materials containing these functional acrylated monomers, CMA and QMA, to be used in environmental remediation. [45] Briefly, the core-shell systems consisting of a magnetite nanoparticle core was coated using a grafting from approach (atom transfer radical polymerization) with PEG400DMA and either CMA or QMA. The adsorption for PCB 126 for these magnetic nanoparticles was subsequently analyzed and fit to the Langmuir model.…”

Hydrogels and Hydrogel Nanocomposites: Enhancing Healthcare through Human and Environmental Treatment

“…Hydrogel nanocomposites have been demonstrated to exhibit higher elasticity, increased mechanical strength, large specific surface area, improved chemical/biological/electrical properties, and/or enhanced swelling/deswelling behavior that cannot be achieved by individual components on their own. [71,72] Hydrogel nanocomposites have been designed from a variety of natural or synthetic hydrogels and a wide range of nanoparticles (i.e., ceramic, metal, polymeric, carbon nanotubes, liposomes, etc.). The following section briefly discusses some of the most recent developments for hydrogel nanocomposites as environmental remediation tools.…”