Health & Environmental Research Online (HERO)


5:3 acid (914637-49-3)


142 References Were Found:

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Synthesis and photochromism of a novel amphiphilic diarylethene bearing two cholic acid groups

Authors: Duan, F; Liu, G; Fan, C; Pu, S (2016) HERO ID: 3860756

[Less] A novel amphiphilic diarylethene with two cholic acid groups, 1,2-bis[2-methyl-5-[3-(1,2,3-triazole) . . . [More] A novel amphiphilic diarylethene with two cholic acid groups, 1,2-bis[2-methyl-5-[3-(1,2,3-triazole) methyl-5-cholic acid-3-thienyl]perfluorocyclopentene, has been successfully synthesized by click reaction for the first time and its photochromic, fluorescence, and electrochemistry properties were systematically investigated. This new compound showed good hydrophilia in methanol/water binary solution (v/v, 1:19). It exhibited photochromism with the notable color change from colorless to red and good fatigue -resistance by photoirradiation. Further study indicated that it also has excellent fluorescence switching property in methanol/water binary solution. (C) 2016 Elsevier Ltd. All rights reserved.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Microfluidic Isoelectric Focusing of Amyloid Beta Peptides Followed by Micropillar-Matrix-Assisted Laser Desorption Ionization-Mass Spectrometry

Authors: Mikkonen, S; Jacksén, J; Roeraade, J; Thormann, W; Emmer, Å (2016) Analytical Chemistry 88:10044-10051. HERO ID: 3860771

[Less] A novel method for preconcentration and purification of the Alzheimer's disease related amyloid beta . . . [More] A novel method for preconcentration and purification of the Alzheimer's disease related amyloid beta (Aβ) peptides by isoelectric focusing (IEF) in 75 nL microchannels combined with their analysis by micropillar-matrix-assisted laser desorption ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS) is presented. A semiopen chip-based setup, consisting of open microchannels covered by a lid of a liquid fluorocarbon, was used. IEF was performed in a mixture of four small and chemically well-defined amphoteric carriers, glutamic acid, aspartyl-histidine (Asp-His), cycloserine (cSer), and arginine, which provided a stepwise pH gradient tailored for focusing of the C-terminal Aβ peptides with a pI of 5.3 in the boundary between cSer and Asp-His. Information about the focusing dynamics and location of the foci of Aβ peptides and other compounds was obtained using computer simulation and by performing MALDI-MS analysis directly from the open microchannel. With the established configuration, detection was performed by direct sampling of a nanoliter volume containing the focused Aβ peptides from the microchannel, followed by deposition of this volume onto a chip with micropillar MALDI targets. In addition to purification, IEF preconcentration provides at least a 10-fold increase of the MALDI-MS-signal. After immunoprecipitation and concentration of the eluate in the microchannel, IEF-micropillar-MALDI-MS is demonstrated to be a suitable platform for detection of Aβ peptides in human cerebrospinal fluid as well as in blood plasma.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Estimated pKa values for the environmentally relevant C1 through C8 perfluorinated sulfonic acid isomers

Authors: Rayne, S; Forest, K (2016) Journal of Environmental Science and Health, Part A: Toxic/Hazardous Substances and Environmental Engineering 51:1018-1023. HERO ID: 3860779

[Less] In order to estimate isomer-specific acidity constants (pKa) for the perfluorinated sulfonic acid (PFSA) . . . [More] In order to estimate isomer-specific acidity constants (pKa) for the perfluorinated sulfonic acid (PFSA) environmental contaminants, the parameterization method 6 (PM6) pKa prediction method was extensively validated against a wide range of carbon oxyacids and related sulfonic/sulfinic acids. Excellent pKa prediction performance was observed for the carbon oxyacids using the PM6 method, but this approach was found to have a severe positive bias for sulfonic/sulfinic acids. To overcome this obstacle, a correlation was developed between non-adjusted PM6 pKa values and the corresponding experimentally obtained/estimated acidity constants for a range of representative alkyl, aryl and halogen-substituted sulfonic acids. Application of this correction to the PM6 values allows for extension of this computational method to a new acid functional group. When used to estimate isomer-specific pKa values for the C1 through C8 PFSAs, the modified PM6 approach suggests an adjusted pKa range from -5.3 to -9.0, indicating that all members of this class of well-known environmental contaminants will be effectively completely dissociated in aquatic systems.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Fuel cell membranes of phosphoric acid-doped poly(benzimidazole/ether/siloxane/amide)/sulfonated polystyrene/silica nanoparticle nanocomposites: A physical property study

Author: Kausar, A (2016) HERO ID: 3860734

[Less] Poly(benzimidazole/ether/siloxane/amide) (PBESA) having siloxane and ether groups in the backbone has . . . [More] Poly(benzimidazole/ether/siloxane/amide) (PBESA) having siloxane and ether groups in the backbone has been prepared using 4-(3,4-diaminophenoxy)benzene-1,2-diamine, bis(carboxypropy)tetramethyldisiloxane, and 4,4-oxydianiline via polyphosphoric acid processes with heating up to 160 degrees C. The sulfonation of polystyrene (PS-S) was conducted using 98% sulfuric acid. Afterward, a series of hybrid membranes using PBESA/PS-S/silica nanoparticles (SiNPs) have been developed with 0.1-2 wt% nanofiller. Later, the membranes were doped with phosphoric acid and subjected to various characterization techniques. Field emission scanning electron micrographs (FESEMs) showed gyroid-like patterning of nanoporous membranes with uniform ionic pathways. Fine water retention capability and higher proton conductivity of new hybrids, owing to consistent porous membrane structure, were observed. Increasing the amount of nanoparticles (0.1-2 wt%) also enhanced the tensile stress of acid-doped PBESA/PS-S/SiNPs nanocomposites from 64.9 to 68.1 MPa. There existed a relationship between nanofiller loading and thermal stability of the membranes. The glass transition temperature of phosphoric acid-doped PBESA/PS-S/SiNPs nanocomposites increased from 202 to 214 degrees C. The membranes also had fine ion exchange capacity (IEC) of around 2.5-3.7 mmol g(-1). Novel membranes with high IEC value achieved high proton conductivity of 1.26-2.74 S cm(-1) in a wide range of humidity values at 80 degrees C, which was higher than that for perfluorinated Nafion((R)) 117 membrane (1.1 x 10(-1) S cm(-1) at 80 degrees C, 94% relative humidity (RH)). The fuel cell (hydrogen/oxygen) using PBESA/PS-S/SiNPs 2 (IEC 3.7 mmol g(-1)) showed better performance than that of Nafion((R)) 117 at 40 degrees C (30% RH).

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Release of per- and polyfluoroalkyl substances (PFASs) from carpet and clothing in model anaerobic landfill reactors

Authors: Lang, JR; Allred, BM; Peaslee, GF; Field, JA; Barlaz, MA (2016) Environmental Science and Technology 50:5024-5032. HERO ID: 3859757

[Less] Discarded carpet and clothing are potential sources of per- and polyfluoroalkyl substances (PFASs) in . . . [More] Discarded carpet and clothing are potential sources of per- and polyfluoroalkyl substances (PFASs) in landfill leachate, but little is known about their release when disposed in landfills. The concentrations of 70 PFASs in the aqueous phase of anaerobic model landfill reactors filled with carpet or clothing were monitored under biologically active and abiotic conditions. For carpet, total PFAS release was greater in live than abiotic reactors, with an average of 8.5 nmol/L and 0.62 nmol/L after 552 days, respectively. Release in live carpet reactors was primarily due to 5:3 fluorotelomer carboxylic acid (FTCA - 3.9 nmol/L) and perfluorohexanoic carboxylic acid (PFHxA - 2.9 nmol/L). For clothing, release was more dependent on sample heterogeneity than the presence of biological activity, with 0.63, 21.7, 2.6, and 6.3 nmol/L for two live and two abiotic reactors after 519 days, respectively. Release in the clothing reactors was largely due to perfluorooctatonic carboxylic acid (PFOA), with low relative concentrations of measured biotransformation precursors (FTCAs). For carpet and clothing reactors, the majority of PFAS release was not measured until after day 100. Results demonstrate that carpet and clothing are likely sources of PFASs in landfill leachate.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Perfluorinated compounds in soil, surface water, and groundwater from rural areas in eastern China

Authors: Chen, S; Jiao, XC; Gai, N; Li, XJ; Wang, XC; Lu, GH; Piao, HT; Rao, Z; Yang, YL (2016) Environmental Pollution 211:124-131. HERO ID: 3858271

[Less] Little research on perfluorinated compounds (PFCs) has been conducted in rural areas, although rural . . . [More] Little research on perfluorinated compounds (PFCs) has been conducted in rural areas, although rural PFC sources are less complicated than in urban and industrial areas. To determine the levels and geographical distribution of 17 PFC compounds, samples of soil, surface water, and groundwater were collected from eight rural areas in eastern China. The total PFC concentrations (∑PFCs) in soils ranged from 0.34 to 65.8 ng/g ∑PFCs in surface waters ranged from 7.0 to 489 ng/L and ∑PFCs in groundwater ranged from 5.3 to 615 ng/L. Ratios of perfluorononanoic acid/perfluorooctanoic acid (PFNA/PFOA), perfluoro-n-butyric acid/perfluorooctanoic acid (PFBA/PFOA), and perfluoroheptanoic acid/perfluorooctanoic acid (PFHpA/PFOA) in rainwater increased due to the fluorine chemical plants in the surrounding rural and urban areas, suggesting that atmospheric precipitation may carry PFCs and their precursors from the fluorochemical industrial area to the adjacent rural areas.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Fast and simple determination of perfluorinated compounds and their potential precursors in different packaging materials

Authors: Zabaleta, I; Bizkarguenaga, E; Bilbao, D; Etxebarria, N; Prieto, A; Zuloaga, O (2016) Talanta 152:353-363. HERO ID: 3860245

[Less] A simple and fast analytical method for the determination of fourteen perfluorinated compounds (PFCs), . . . [More] A simple and fast analytical method for the determination of fourteen perfluorinated compounds (PFCs), including three perfluoroalkylsulfonates (PFSAs), seven perfluorocarboxylic acids (PFCAs), three perfluorophosphonic acids (PFPAs) and perfluorooctanesulfonamide (PFOSA) and ten potential precursors, including four polyfluoroalkyl phosphates (PAPs), four fluorotelomer saturated acids (FTCAs) and two fluorotelomer unsaturated acids (FTUCAs) in different packaging materials was developed in the present work. In order to achieve this objective the optimization of an ultrasonic probe-assisted extraction (UPAE) method was carried out before the analysis of the target compounds by liquid-chromatography-triple quadrupole-tandem mass spectrometry (LC-QqQ-MS/MS). 7 mL of 1 % acetic acid in methanol and a 2.5-min single extraction cycle were sufficient for the extraction of all the target analytes. The optimized analytical method was validated in terms of recovery, precision and method detection limits (MDLs). Apparent recovery values after correction with the corresponding labeled standard were in the 69-103 % and 62-98 % range for samples fortified at 25 ng/g and 50 ng/g concentration levels, respectively and MDL values in the 0.6-2.2 ng/g range were obtained. The developed method was applied to the analysis of plastic (milk bottle, muffin cup, pre-cooked food wrapper and cup of coffee) and cardboard materials (microwave popcorn bag, greaseproof paper for French fries, cardboard box for pizza and cinema cardboard box for popcorn). To the best of our knowledge, this is the first method that describes the determination of fourteen PFCs and ten potential precursors in packaging materials. Moreover, 6:2 FTCA, 6:2 FTUCA and 5:3 FTCA analytes were detected for the first time in microwave popcorn bags.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Studies on the interaction of perfluorononanoic acid with human serum albumin by multi-spectroscopic, molecular docking and isothermal titration calorimetry techniques

Authors: Hu, TY; Huang, F; Zhou, SS; Liu, Y (2016) Guangpuxue yu Guangpu Fenxi / Spectroscopy and Spectral Analysis 36:4141-4147. HERO ID: 3860179

[Less] Perfluorononanoic acid (PFNA) is the third most frequently detected in serum among all perfluoroalkyl . . . [More] Perfluorononanoic acid (PFNA) is the third most frequently detected in serum among all perfluoroalkyl acids (PFAAs) which is a kind of toxic emerging environmental contaminant. The influence of PFNA on the conformation and even function of human serum albumin (HSA) is still just at the beginning of research. The attempt of this paper was to completely elucidate the interaction mechanism of PFNA with HSA by means of multi-spectroscopic, molecular docking and isothermal titration calorimetry (ITC) techniques. The inner filter effect of all fluorescence data in the paper was eliminated to get accurate binding parameters. The results showed that the fluorescence of HSA was quenched by PFNA through a combined quenching procedure of dynamic and static quenching. Through site marker competitive experiments, subdomain IIA. of HSA had been assigned to possess the high-affinity binding site of PFNA. Furthermore, molecular docking reconfirmed that PFNA was bound in subdomain IIA mainly through polar force, hydrophobic interaction and halogen-bond, and the calculated free energy was -26.54 kJ.mol(-1) which indicated that the PFNA molecule exhibited large binding affinity towards HSA. The thermodynamic characterizations of two different classes of binding sites by ITC displayed that the first class with a higher affinity constant was dominated by an enthalpic contribution due to electrostatic interactions and halogen-bond, whereas the second class with a lower affinity constant was preponderated by hydrophobic interaction. The three-dimensional fluorescence revealed that the conformation of HSA was changed and the hydrophobicity of the Trp and Tyr residues microenvironment increased after formation of PFNA-HSA complex. The alterations of the protein secondary structure were quantitatively calculated from circular dichroism (CD) spectroscopy with reduction of a-helix content about 14.3%, beta-sheet 5.3%, beta-turn 3.5%, and augment in random content from 14.4% to 37.5%. Above results revealed that the binding of PFNA with HSA can alter the secondary structure of HSA, further probably affecting HSA physiological function. The results can provide insights with the binding mechanism of PFNA with HSA and salient biophysical and biochemical clues on elucidating the transport and distribution of PFNA in vivo.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Aerobic biotransformation of polyfluoroalkyl phosphate esters (PAPs) in soil

Authors: Liu, C; Liu, J (2016) Environmental Pollution 212:230-237. HERO ID: 3856871

[Less] Microbial transformation of polyfluoroalkyl phosphate esters (PAPs) into perfluorocarboxylic acids (PFCAs) . . . [More] Microbial transformation of polyfluoroalkyl phosphate esters (PAPs) into perfluorocarboxylic acids (PFCAs) has recently been confirmed to occur in activated sludge and soil. However, there lacks quantitative information about the half-lives of the PAPs and their significance as the precursors to PFCAs. In the present study, the biotransformation of 6:2 and 8:2 diPAP in aerobic soil was investigated in semi-dynamics reactors using improved sample preparation methods. To develop an efficient extraction method for PAPs, six different extraction solvents were compared, and the phenomenon of solvent-enhanced hydrolysis was investigated. It was found that adding acetic acid could enhance the recoveries of the diPAPs and inhibit undesirable hydrolysis during solvent extraction of soil. However 6:2 and 8:2 monoPAPs, which are the first breakdown products from diPAPs, were found to be unstable in the six solvents tested and quickly hydrolyzed to form fluorotelomer alcohols. Therefore reliable measurement of the monoPAPs from a live soil was not achievable. The apparent DT50 values of 6:2 diPAP and 8:2 diPAP biotransformation were estimated to be 12 and > 1000 days, respectively, using a double first-order in parallel model. At the end of incubation of day 112, the major degradation products of 6:2 diPAP were 5:3 fluorotelomer carboxylic acid (5:3 acid, 9.3% by mole), perfluoropentanoic acid (PFPeA, 6.4%) and perfluorohexanoic acid (PFHxA, 6.0%). The primary product of 8:2 diPAP was perfluorooctanoic acid (PFOA, 2.1%). The approximately linear relationship between the half-lives of eleven polyfluoroalkyl and perfluoroalkyl substances (PFASs, including 6:2 and 8:2 diPAPs) that biotransform in aerobic soils and their molecular weights suggested that the molecular weight is a good indicator of the general stability of low-molecular-weight PFAS-based compounds in aerobic soils.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Biotransformation potential of 6:2 fluorotelomer sulfonate (6:2 FTSA) in aerobic and anaerobic sediment

Authors: Zhang, S; Lu, X; Wang, N; Buck, RC (2016) Chemosphere 154:224-230. HERO ID: 3857383

[Less] Aqueous film-forming foam (AFFF) products are used in industrial and military firefighting around the . . . [More] Aqueous film-forming foam (AFFF) products are used in industrial and military firefighting around the globe. These products contain fluoroalkylthioamido sulfonates, fluoroalkylthiobetaine, and other related substances as the major ingredients, which can be biotransformed in the environment to form 6:2 fluorotelomer sulfonate (6:2 FTSA, F(CF2)6CH2CH2SO3-) as one of the major initial biotransformation products. Limited information is available on 6:2 FTSA aerobic biotransformation in activated sludge and pure microbial culture. This is the first study to report 6:2 FTSA biotransformation in aerobic and anaerobic sediment. 6:2 FTSA was rapidly biotransformed in aerobic river sediment with a half-life less than 5 d. Major stable transformation products observed after 90 d included 5:3 Acid [F(CF2)5CH2CH2COOH), 16 mol%), PFPeA [F(CF2)4COOH, 21 mol%] and PFHxA (F(CF2)5COOH, 20 mol%). 6:2 fluorotelomer alcohol [6:2 FTOH, F(CF2)6CH2CH2OH] was readily biotransfomed whereas 6:2 FTSA biotransformation did not occur in anaerobic sediment over 100 d, indicating that the enzymatic desulfonation step limited 6:2 FTSA biotransformation in anaerobic sediment. These results suggest that 6:2 FTSA related products, after release to the aerobic environment, is likely to biodegrade forming 5:3 Acid, PFPeA and PFHxA. This study also indicates that 6:2 FTSA formed from its aforementioned precursors may be persistent in the anaerobic environment after their potential release. This work provides insight to understanding the fate and environmental loading of AFFF-related products and their major transformation products in the environment.