Enhanced host–guest complexation of short chain perfluoroalkyl substances with positively charged β-cyclodextrin derivatives

Adsorbents comprising swellable organically modified silica were characterized to optimize the adsorption of a wide range of perfluoroalkyl substances from water.

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Occurrence and characteristics of perfluoroalkyl substances (PFASs) in electroplating industrial wastewater

Water Science & Technology ◽

10.2166/wst.2019.092 ◽

2019 ◽

Vol 79 (4) ◽

pp. 731-740 ◽

Cited By ~ 1

Author(s):

Tang Jiawei ◽

Zhang Yizhen ◽

Sun Jiajun ◽

Shi Xuelu ◽

Sun Chao ◽

...

Keyword(s):

Industrial Wastewater ◽

Drainage System ◽

Principal Component ◽

Short Chain ◽

Perfluoroalkyl Substances ◽

Substitution Effects ◽

Negative Effects ◽

Industrial Parks ◽

Total Concentrations ◽

Very High

Abstract The potential negative effects of perfluoroalkyl substances (PFASs) discharged into aquatic environments are drawing increasing attention. However, little research has been undertaken on PFASs in wastewater from electroplating industrial parks. In this study, the concentration profiles and geographical distribution of 11 PFASs were analyzed in water samples collected from different production workshops and an artificial landscaped lake. The total concentrations of PFASs (Σ11PFASs) at various points in the production drainage system range from 229.5 to 5410.6 ng/L, and are mainly contributed by nickel plating, pickling, and the cyanide bright silver plating procedure, which correspond to cyanide-containing and acid-alkali wastewater conditioning tanks. Wastewater treatment by oxidation and precipitation removed 52.6% and 20% of PFASs, respectively. Σ11PFASs in effluents is about 538 ng/L, which consists of perfluorooctanoic acid (PFOA, 430.5 ng/L), followed by perfluorooctane sulfonate (PFOS, 35.27 ng/L), perfluorohexane sulfonate (PFHxS, 28.05 ng/L), and perfluorohexanoic acid (PFHxA, 18.3 ng/L). Principal component analysis suggests that the Σ11PFASs in electroplating wastewater is very high and short-chain (C4–C8) PFASs have high detection and contribution rates. As a result, much attention should be paid to the increase in short-chain substitution effects and pollution around the factory area.

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Chiral Nafion membranes prepared by strong electrostatic binding of multiply positively charged β-cyclodextrin derivatives for tryptophan racemic mixtures’ separation

Materials Today Communications ◽

10.1016/j.mtcomm.2021.102234 ◽

2021 ◽

Vol 27 ◽

pp. 102234 ◽

Cited By ~ 1

Author(s):

Petr Kasal ◽

Marine Michel ◽

Jana Gaálová ◽

Petra Cuřínová ◽

Pavel Izák ◽

...

Keyword(s):

Cyclodextrin Derivatives ◽

Racemic Mixtures ◽

Electrostatic Binding ◽

Nafion Membranes ◽

Positively Charged

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Single Isomer N-Heterocyclic Cyclodextrin Derivatives as Chiral Selectors in Capillary Electrophoresis

Molecules ◽

10.3390/molecules26175271 ◽

2021 ◽

Vol 26 (17) ◽

pp. 5271

Author(s):

Ida Fejős ◽

Eszter Kalydi ◽

Edit Luca Kukk ◽

Mimimorena Seggio ◽

Milo Malanga ◽

...

Keyword(s):

Chiral Recognition ◽

Cyclodextrin Derivatives ◽

Ph Titration ◽

Chiral Selectors ◽

Single Isomer ◽

1H Nuclear Magnetic Resonance ◽

Pka Determination ◽

Capillary Electrophoretic ◽

2D Roesy ◽

Positively Charged

In order to better understand the chiral recognition mechanisms of positively charged cyclodextrin (CD) derivatives, the synthesis, the pKa determination by 1H nuclear magnetic resonance (NMR)-pH titration and a comparative chiral capillary electrophoretic (CE) study were performed with two series of mono-substituted cationic single isomer CDs. The first series of selectors were mono-(6-N-pyrrolidine-6-deoxy)-β-CD (PYR-β-CD), mono-(6-N-piperidine-6-deoxy)-β-CD (PIP-β-CD), mono-(6-N-morpholine-6-deoxy)-β-CD (MO-β-CD) and mono-(6-N-piperazine-6-deoxy)-β-CD (PIPA-β-CD), carrying a pH-adjustable moiety at the narrower rim of the cavity, while the second set represented by their quaternarized, permanently cationic counterparts: mono-(6-N-(N-methyl-pyrrolidine)-6-deoxy)-β-CD (MePYR-β-CD), mono-(6-N-(N-methyl-piperidine)-6-deoxy)-β-CD (MePIP-β-CD), mono-(6-N-(N-methyl-morpholine)-6-deoxy)-β-CD (MeMO-β-CD) and mono-(6-N-(4,4-N,N-dimethyl-piperazine)-β-CD (diMePIPA-β-CD). Based on pH-dependent and selector concentration-dependent comparative studies of these single isomer N-heterocyclic CDs presented herein, it can be concluded that all CDs could successfully be applied as chiral selectors for the enantiodiscrimination of several negatively charged and zwitterionic model racemates. The substituent-dependent enantiomer migration order reversal of dansylated-valine using PIP-β-CD contrary to PYP-β-CD, MO-β-CD and PIPA-β-CD was also studied by 1H- and 2D ROESY NMR experiments.

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Protamine-DNA interaction

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081863 ◽

1978 ◽

Vol 36 (2) ◽

pp. 200-201

Author(s):

D.P. Bazett-Jones ◽

F.P. Ottensmeyer

Keyword(s):

Small Volume ◽

Double Helix ◽

Dna Interaction ◽

Dark Field ◽

Sperm Head ◽

Nuclear Proteins ◽

Field Electron Microscopy ◽

Dark Field Electron ◽

Dna Double Helix ◽

Positively Charged

Dark field electron microscopy has been used for the study of the structure of individual macromolecules with a resolution to at least the 5Å level. The use of this technique has been extended to the investigation of structure of interacting molecules, particularly the interaction between DNA and fish protamine, a class of basic nuclear proteins of molecular weight 4,000 daltons.Protamine, which is synthesized during spermatogenesis, binds to chromatin, displaces the somatic histones and wraps up the DNA to fit into the small volume of the sperm head. It has been proposed that protamine, existing as an extended polypeptide, winds around the minor groove of the DNA double helix, with protamine's positively-charged arginines lining up with the negatively-charged phosphates of DNA. However, viewing protamine as an extended protein is inconsistent with the results obtained in our laboratory.

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Structure and Interaction of Protamine by Dark Field Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100090786 ◽

1976 ◽

Vol 34 ◽

pp. 160-161

Author(s):

D.P. Bazett-Jones ◽

F.P. Ottensmeyer

Keyword(s):

Electron Microscopy ◽

Dark Field ◽

Amino Acid Sequences ◽

Dimensional Structure ◽

3 Dimensional ◽

Field Electron ◽

Proposed Model ◽

Field Electron Microscopy ◽

Dark Field Electron ◽

Positively Charged

It has been shown for some time that it is possible to obtain images of small unstained proteins, with a resolution of approximately 5Å using dark field electron microscopy (1,2). Applying this technique, we have observed a uniformity in size and shape of the 2-dimensional images of pure specimens of fish protamines (salmon, herring (clupeine, Y-l) and rainbow trout (Salmo irideus)). On the basis of these images, a model for the 3-dimensional structure of the fish protamines has been proposed (2).The known amino acid sequences of fish protamines show stretches of positively charged arginines, separated by regions of neutral amino acids (3). The proposed model for protamine structure (2) consists of an irregular, right-handed helix with the segments of adjacent arginines forming the loops of the coil.

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Enhanced type I photoreaction of indocyanine green via electrostatic-force-driven aggregation

Nanoscale ◽

10.1039/d0nr01208d ◽

2020 ◽

Vol 12 (17) ◽

pp. 9517-9523 ◽

Cited By ~ 3

Author(s):

Huizhen Fan ◽

Yu Fan ◽

Wenna Du ◽

Rui Cai ◽

Xinshuang Gao ◽

...

Keyword(s):

Mesoporous Silica ◽

Indocyanine Green ◽

Electrostatic Force ◽

Type I ◽

Positively Charged

ICG forms aggregates in positively charged mesoporous silica, which show an enhanced type I photoreaction pathway.

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Influence of nascent polypeptide positive charges on translation dynamics

Biochemical Journal ◽

10.1042/bcj20200303 ◽

2020 ◽

Vol 477 (15) ◽

pp. 2921-2934

Author(s):

Rodrigo D. Requião ◽

Géssica C. Barros ◽

Tatiana Domitrovic ◽

Fernando L. Palhano

Keyword(s):

Mrna Decay ◽

Translation Termination ◽

Published Data ◽

Translation Efficiency ◽

Amino Acid Residues ◽

High Concentration ◽

Strong Argument ◽

Translation Arrest ◽

Exit Tunnel ◽

Positively Charged

Protein segments with a high concentration of positively charged amino acid residues are often used in reporter constructs designed to activate ribosomal mRNA/protein decay pathways, such as those involving nonstop mRNA decay (NSD), no-go mRNA decay (NGD) and the ribosome quality control (RQC) complex. It has been proposed that the electrostatic interaction of the positively charged nascent peptide with the negatively charged ribosomal exit tunnel leads to translation arrest. When stalled long enough, the translation process is terminated with the degradation of the transcript and an incomplete protein. Although early experiments made a strong argument for this mechanism, other features associated with positively charged reporters, such as codon bias and mRNA and protein structure, have emerged as potent inducers of ribosome stalling. We carefully reviewed the published data on the protein and mRNA expression of artificial constructs with diverse compositions as assessed in different organisms. We concluded that, although polybasic sequences generally lead to lower translation efficiency, it appears that an aggravating factor, such as a nonoptimal codon composition, is necessary to cause translation termination events.

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