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Over 9000 types of per- and polyfluoroalkyl substances (PFASs) have been produced that exhibit environmental persistence, bioaccumulation and biotoxicity, and pose a potential hazard to human health. Although metal–organic frameworks (MOFs) are promising structure-based materials for adsorbing PFASs, the enormous structural diversity and variability of the pharmacologic action of PFASs present challenges to the development of structure-based adsorbents. To address this issue, we propose an in situ platform for the high-throughput identification of efficient MOF sorbents that can adsorb PFASs and their metabolism using a filter-chip-solid phase extraction-mass spectrometry (SPE-MS) system. As a proof of concept, we screened BUT-16 as an attractive material for in situ fluorotelomer alcohol (FTOH) adsorption. The results demonstrated that FTOH molecules were adsorbed around the surface of the large hexagonal pores of BUT-16 by forming multiple hydrogen bonding interactions with its Zr6 clusters. The FTOH removal efficiency of the BUT16 filter was 100% over a period of 1 min. To determine the FTOH metabolism effects in different organs, HepG2 human hepatoma, HCT116 colon cancer, renal tubular HKC, and vascular endothelial HUVEC cells were cultured on a microfluidic chip, and SPE-MS was used to track a variety of cell metabolites in real time. Overall, the filter-Chip-SPE-MS system is a versatile and robust platform for the real-time monitoring of noxious pollutant detoxification, biotransformation, and metabolism, which facilitates pollutant antidote development and toxicology assay. [ABSTRACT FROM AUTHOR]

Chitosan (CS) based nanofibrous membranes were fabricated via hybrid electrospinning of chitosan (CS) and poly(ε-caprolactone) (PCL) or poly(ε-caprolactone)-block-poly(ethylene glycol) (PCL-b-PEG) copolymers for the adsorption of dyes from aqueous solution. The amphiphilic block polymers were obtained by polymerization of PCL and different molecular weights of PEG. It was observed that the secondary fiber and core–shell structure could be controlled by PEG segments. The results of XPS showed that as the molecular weight of the PEG segments increased, the content of CS on the fiber surface increased. The parameters of adsorption time, initial concentration and pH values on the adsorption capacity were studied. The adsorption experiments showed that the adsorption process toward Congo red (CR) on CS-based membranes fitted well with the pseudo-second-order model and Langmuir isotherm model. The CS-based membranes with PEG molecular weight of 5 kDa possessed good reusability and the maximum adsorption capacity calculated from the Langmuir model was 291.55 mg g−1. The existence of intermolecular hydrogen bonds between CS and PCL-b-PEG copolymer reduced the loss of CS. Therefore, CS-based membranes would be promising materials for water remediation. [ABSTRACT FROM AUTHOR]

Chitosan/poly(ethylene oxide)/permutit (CS/PEO/PT) composite nanofibers were prepared via electrospinning and their potential application in the removal of hexavalent chromium (Cr(vi)) from aqueous solutions was studied in detail. SEM results showed that the nanofibers were homogeneous and bead-free. XRD and DSC results demonstrated that there were strong interactions among CS, PEO and PT. The solubility test showed that the CS/PEO/PT composite membrane had excellent durability in water. The CS/PEO/PT-1% nanofibers exhibited the best adsorption performance for Cr(vi) ions in acidic solution (pH = 3) and at a low Cr(vi) concentration of 50 mg L−1. The maximum adsorption capacity reached 208 mg g−1. The adsorption kinetics and equilibrium data were well described by pseudo-second-order kinetic and Langmuir isotherm models, respectively. According to the results of FTIR and XPS analyses, protonation, ion exchange, electrostatic interactions and redox reactions were involved in the adsorption process. All the results indicated that the electrospun CS/PEO/PT nanofibers could be used as promising absorbents for the removal of Cr(vi). [ABSTRACT FROM AUTHOR]

3D ordered silver nanoshells silica photonic crystal beads as a novel encoded surface enhanced Raman scattering substrate are proposed for the development of highly efficient multiplex bioassays. [ABSTRACT FROM AUTHOR]

Novel quantum-dot-tagged photonic crystal beads were fabricated for multiplex detection of tumor markers via self-assembly of quantum dot-embedded polystyrene nanospheres into photonic crystal beads through a microfluidic device.