Health & Environmental Research Online (HERO)


PFHpA (375-85-9)


337 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

Determination of perfluorinated carboxylic acids in biological samples by high-performance liquid chromatography

Authors: Ohya, T; Kudo, N; Suzuki, E; Kawashima, Y (1998) Journal of Chromatography B: Biomedical Sciences and Applications 720:1-7. HERO ID: 2906110

[Less] This paper describes a method for the quantitative determination of perfluorinated carboxylic acids . . . [More] This paper describes a method for the quantitative determination of perfluorinated carboxylic acids (PFCAs), perfluorohexanoic acid (C6-PFCA), perfluoroheptanoic acid (C7-PFCA), perfluorooctanoic acid (C8-PFCA), perfluorononanoic acid (C9-PFCA) and perfluorodecanoic acid (C10-PFCA), in biological samples. PFCA in liver homogenates was extracted as an ion pair with tetrabutylammonium (TBA) ion into organic solvent, then the PFCA was derivatized with 3-bromoacetyl-7-methoxycoumarin (BrAMC) and quantified by HPLC with fluorescence detection. This method is applicable for the studies on tissue accumulation and elimination of PFCAs in animals after the administration.

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

F-19, C-13 single- and two-bond 2D NMR correlations in perfluoroheptanoic acid

Author: Ribeiro, AA (1997) Journal of Fluorine Chemistry 83:61-66. HERO ID: 3859900

[Less] The first F-19, C-13 single- and multi-bond 2D NMR correlations using fluorine detection methods are . . . [More] The first F-19, C-13 single- and multi-bond 2D NMR correlations using fluorine detection methods are reported for a perfluorinated alkyl chain. These heteronuclear correlations are observed in perfluoroheptanoic acid and combined with F-19-decoupled C-13 data and homonuclear F-19, F-19 COSY to derive a full set of unequivocal F-19 and C-13 assignments. (C) Elsevier Science S.A.

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

Adsolubilization of fluorocarbon alcohols into perfluoroheptanoate admicelles formed on alumina

Authors: Lai, CL; Orear, EA; Harwell, JH; Hwa, MJ (1997) HERO ID: 3859915

[Less] Sodium perfluoroheptanoate adsorption and adsolubilization of small aliphatic fluorocarbon alcohols . . . [More] Sodium perfluoroheptanoate adsorption and adsolubilization of small aliphatic fluorocarbon alcohols into surface aggregates formed on alumina was investigated. Higher concentrations and increasing hydrophobicity of the adsolubilizate enhanced surfactant adsorption below the plateau region. Partitioned amounts of the fluorocarbon alcohols rose with the alcohol supernatant concentration and chain length. Aggregation numbers were estimated with the two-site adsolubilization model.

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

Formation of fluorocarbon surfactant reversed micelles in a halosolvent

Authors: Lai, CL; Orear, EA; Harwell, JH (1996) HERO ID: 3859913

[Less] The constitution of reversed micelles of C6F13COOH (perfluoroheptanoic acid, PFHA) in a chlorofluorocarbon . . . [More] The constitution of reversed micelles of C6F13COOH (perfluoroheptanoic acid, PFHA) in a chlorofluorocarbon medium (1,1,2-trichlorotrifluoroethane, TCFE) was characterized by a number of techniques, including IR, NMR, and UV-vis and fluorescence probes. Dimensions of these reversed micelles were determined by quasielastic light scattering. With increasing concentration of surfactant in TCFE, the estimated diameter of the water pool in the reversed micelles increased, the estimated aggregation number of the reversed micelles increased, and the estimated wt% water increased. These estimates were consistent with the results of the probe studies and Karl Fischer titrations. Adsorption of fluoroacids from this solvent onto alumina showed cooperative interactions between head groups. (C) 1996 Academic Press. Inc.

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

Influence of carbon chain length on the hepatic effects of perfluorinated fatty acids. A 19F- and 31P-NMR investigation

Authors: Goecke-Flora, CM; Reo, NV (1996) Chemical Research in Toxicology 9:689-695. HERO ID: 2906765

[Less] Using nuclear magnetic resonance (NMR) spectroscopy, we investigated the importance of carbon chain . . . [More] Using nuclear magnetic resonance (NMR) spectroscopy, we investigated the importance of carbon chain length with regard to the hepatic effects associated with perfluoro-n-carboxylic acids. Male F-344 rats were administered a single intraperitoneal dose of either perfluoro-n-heptanoic acid (C7-PFA), perfluoro-n-nonanoic acid (C9-PFA), or perfluoro-n-undecanoic acid (C11-PFA). Data from previous studies involving perfluoro-n-octanoic acid (C8-PFA) and perfluoro-n-decanoic acid (C10-PFA) are included for comparison. Food consumption/body weight was monitored daily for all groups. C9- and C11-PFA treatment yields a prolonged hypophagic response while C7-PFA shows a more acute response. Fluorine-19 NMR spectra of urine and bile samples show no evidence of fluorometabolites and suggest that the distribution of perfluorocarbons into urine or bile is dependent upon carbon chain length. The aqueous solubility of C7-PFA appears to facilitate rapid urinary excretion, similar to that observed for C8-PFA. The relative hydrophobicity of C9- and C11-PFA appears to favor biliary enterohepatic recirculation, yielding a more protracted toxicity, similar to C10-PFA. Phosphorus-31 NMR studies of liver in vivo and liver extracts show that perfluorocarbons of > or = C9 carbons produce a significant increase in liver phosphocholine concentration. These data are discussed with regard to the impact of these chemicals on hepatic phospholipid metabolism. Hepatic peroxisomal fatty acyl CoA-oxidase activity (FAO) was measured to determine if C7-, C9-, and C11-PFA are peroxisome proliferators. Data indicate that the induction of peroxisomal enzyme activity by perfluorocarbons requires a chain length greater than seven carbons. In general, these results demonstrate the significance of carbon chain length in the hepatotoxic response and provide clues toward understanding the processes involved in the biological activities associated with exposure to these compounds.

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 acid alternatives to trifluoroacetic acid for reversed-phase high-performance liquid chromatography

Authors: Pearson, JD; Mccroskey, MC (1996) Journal of Chromatography A 746:277-281. HERO ID: 3858375

[Less] Over the past decade trifluoroacetic acid (TFA) has become the ion-pairing agent (IPA) of choice for . . . [More] Over the past decade trifluoroacetic acid (TFA) has become the ion-pairing agent (IPA) of choice for reversed-phase high-performance liquid chromatography (RP-HPLC) of peptides and proteins. Reagent grade TFA is highly pure, water soluble, transparent at 220 nm and readily volatile. A drawback of this universal appeal is that several alternative perfluorinated carboxylic acids tend to be overlooked when TFA does not work in a particular separation. Examples are given comparing TFA selectivity with those of pentafluoropropionic acid, heptafluorobutyric acid, perfluoropentanoic acid, perfluorohexanoic acid and perfluoroheptanoic acid. We have found that increasing the IPA n-alkyl chain length can resolve sample components that otherwise co-elute in the void volume of TFA-based RP-HPLC. Examples are given for the resolution of an oligoglycine series and enhanced selectivity for a bovine hypothalamic extract.

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

Modification of the surface of chemical fibres with fluorine-containing copolymers (review)

Authors: Sletkina, LS; Pedina, LV; Kolokolkina, NV (1995) HERO ID: 3981606

[Less] Modification of chemical fibres with copolymers of 1,1-dihydroperfluoro-heptyl acrylate (PFHA) to decrease . . . [More] Modification of chemical fibres with copolymers of 1,1-dihydroperfluoro-heptyl acrylate (PFHA) to decrease their wettability was systematically investigated and some characteristics of this process were established. It was shown that the effectiveness of modification is determined by the method of treating the fibres with the copolymer modifiers, the molecular composition of these copolymers, and the colloid chemical properties of the latexes based on them. Treatment of the fibres with copolymers with functionally active groups capable of reacting with the macromolecule of the fibre-forming polymer and cross-linking on the surface of the fibre is the most effective method of modification. Substitution of incomplete fluorinated alcohols or unfluorinated monomers for the acrylates in the PFHA copolymer reduces their effectiveness in modification. Copolymers of PFHA with hydrophilic monomers capable of being orientedly sorbed by the fibre due to its amphiphilic nature and forming surfaces with low energy are an exception. For effective use of the copolymer modifier, the latexes of these copolymers should have certain colloid chemical properties: the particle charge, adsorption saturation, and aggregate stability should be optimum, which will ensure their stability during preparation, storage, and use.

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

FORMATION OF POLY(TETRAFLUOROETHYLENE) THIN-FILMS ON ALUMINA BY ADMICELLAR POLYMERIZATION

Authors: Lai, CL; Harwell, JH; Orear, EA (1995) HERO ID: 3859912

[Less] Partitioning of tetrafluoroethylene gas into admicelles of sodium perfluoroheptanoate on alumina was . . . [More] Partitioning of tetrafluoroethylene gas into admicelles of sodium perfluoroheptanoate on alumina was measured in a high-pressure reactor. Polymerization of tetrafluoroethylene within the adsorbed surfactant bilayer took place after thermal initiation with the formation of fluorocarbon thin films on aluminum oxide powder. In the formation of poly(tetrafluoroethylene) (PTFE), the effects of surfactant concentration and of initiator concentration were studied. Modified powder was characterized by a number of techniques including Fourier transform infrared (FTIR) spectroscopy, wavelength-dispersive spectroscopy (WDS), atomic force microscopy (AFM), and wettability testing. Measurements of friction coefficients and contact angles verified that a thin poly(tetrafluoroethylene) film was formed on alumina plates using the same procedure.

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

REACTIONS OF BENZAMIDOXIME AND ITS SODIUM-SALT WITH METHYL-ESTERS OF FLUORINATED ACIDS

Authors: Ilin, VV; Kabakchi, EV; Ignatenko, AV (1993) HERO ID: 3859903

[Less] The reactions of benzamidoxime and its sodium salt with methyl esters of fluorinated acids at 20-100-degrees-C . . . [More] The reactions of benzamidoxime and its sodium salt with methyl esters of fluorinated acids at 20-100-degrees-C give 1,2,4-oxadiazoles or O-addition products.

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

VOLATILE ION-PAIRING AGENTS FOR LIQUID-CHROMATOGRAPHIC THERMOSPRAY MASS-SPECTROMETRIC DETERMINATION OF AMINO-ACIDS AND AMINO-ACID AMIDES

Authors: Vanleuken, RGJ; Kwakkenbos, GTC; Duchateau, ALL (1993) Journal of Chromatography A 647:131-136. HERO ID: 3858440

[Less] The behaviour of volatile ion-pairing agents in terms of performance of the combined liquid chromatography-mass . . . [More] The behaviour of volatile ion-pairing agents in terms of performance of the combined liquid chromatography-mass spectrometry is described. The applicability of heptafluorobutanoic acid, tridecafluoroheptanoic acid and nonadecafluorodecanoic acid as volatile ion-pairing agents is demonstrated by the analysis of mixtures of amino acids and the corresponding amino acid amides. Translation of a non-volatile to a volatile ion-pair system that is suitable for thermospray mass spectrometry is described. Using nonadecafluorodecanoic acid, the retention times of the compounds studied were comparable to those obtained with n-dodecylsulphonic acid. Further, with nonadecafluorodecanoic acid, the repeatability of the tests and the calibration graphs of the compounds investigated were good. The sensitivity of the mass spectrometer towards the compounds of interest was greatly improved by postcolumn addition of trifluoroacetic acid and ionization with gaseous ammonia. Using nonadecafluorodecanoic acid, the method was applied to the analysis of samples from bio-organic synthesis.