Influence of salt on the structure of DMPG studied by SAXS and optical microscopy
Autor(a) principal: | |
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Data de Publicação: | 2008 |
Outros Autores: | , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UNIFESP |
Texto Completo: | http://repositorio.unifesp.br/handle/11600/30535 http://dx.doi.org/10.1016/j.bbamem.2007.12.005 |
Resumo: | Aqueous dispersions of 50 mM dimyristoylphosphatidylglycerol (DMPG) in the presence of increasing salt concentrations (2-500 mM NaCl) were studied by small angle X-ray scattering (SAXS) and optical microscopy between 15 and 35 degrees C. SAXS data show the presence of a broad peak around q similar to 0.12 angstrom(-1) at all temperatures and conditions, arising from the electron density contrasts within the bilayer. Up to 100 mM NaCl, this broad peak is the main feature observed in the gel and fluid phases. At higher ionic strength (250-500 mM NaCl), an incipient lamellar repeat distance around d= 90-100 angstrom is detected superimposed to the bilayer form factor. the data with high salt were fit and showed that the emergent Bragg peak is due to loose multilamellar structures, with the local order vanishing after similar to 4d. Optical microscopy revealed that up to 20 mM NaCl, DMPG is arranged in submicroscopic vesicles. Giant (loose) multilamellar vesicles (MLVs) start to appear with 50 mM NaCl, although most lipids are arranged in small vesicles. As the ionic strength increases, more and denser MLVs are seen, up to 500 mM NaCl, when MLVs are the prevailing structure. the DLVO theory could account for the experimentally found interbilayer distances. (c) 2007 Elsevier B.V. All rights reserved. |
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Fernandez, Roberto MoratoRiske, Karin do Amaral [UNIFESP]Amaral, Lia Queiroz doItri, RosangelaLamy, Maria Teresa MouraUniversidade Federal de São Paulo (UNIFESP)2016-01-24T13:49:40Z2016-01-24T13:49:40Z2008-04-01Biochimica Et Biophysica Acta-biomembranes. Amsterdam: Elsevier B.V., v. 1778, n. 4, p. 907-916, 2008.0005-2736http://repositorio.unifesp.br/handle/11600/30535http://dx.doi.org/10.1016/j.bbamem.2007.12.005WOS000255228000011.pdf10.1016/j.bbamem.2007.12.005WOS:000255228000011Aqueous dispersions of 50 mM dimyristoylphosphatidylglycerol (DMPG) in the presence of increasing salt concentrations (2-500 mM NaCl) were studied by small angle X-ray scattering (SAXS) and optical microscopy between 15 and 35 degrees C. SAXS data show the presence of a broad peak around q similar to 0.12 angstrom(-1) at all temperatures and conditions, arising from the electron density contrasts within the bilayer. Up to 100 mM NaCl, this broad peak is the main feature observed in the gel and fluid phases. At higher ionic strength (250-500 mM NaCl), an incipient lamellar repeat distance around d= 90-100 angstrom is detected superimposed to the bilayer form factor. the data with high salt were fit and showed that the emergent Bragg peak is due to loose multilamellar structures, with the local order vanishing after similar to 4d. Optical microscopy revealed that up to 20 mM NaCl, DMPG is arranged in submicroscopic vesicles. Giant (loose) multilamellar vesicles (MLVs) start to appear with 50 mM NaCl, although most lipids are arranged in small vesicles. As the ionic strength increases, more and denser MLVs are seen, up to 500 mM NaCl, when MLVs are the prevailing structure. the DLVO theory could account for the experimentally found interbilayer distances. (c) 2007 Elsevier B.V. All rights reserved.Universidade Federal de São Paulo, Inst Fis, BR-05315970 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista de Medicina (EPM)Web of Science907-916engElsevier B.V.Biochimica Et Biophysica Acta-biomembraneshttp://www.elsevier.com/about/open-access/open-access-policies/article-posting-policyinfo:eu-repo/semantics/openAccessgel-fluid phase transitionintermediate phasecharged phospholipidDLVO theoryInfluence of salt on the structure of DMPG studied by SAXS and optical microscopyinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articlereponame:Repositório Institucional da UNIFESPinstname:Universidade Federal de São Paulo (UNIFESP)instacron:UNIFESPORIGINALWOS000255228000011.pdfapplication/pdf1093856${dspace.ui.url}/bitstream/11600/30535/1/WOS000255228000011.pdf113a3a1c4505af639d0f15aa6468c58bMD51open accessTEXTWOS000255228000011.pdf.txtWOS000255228000011.pdf.txtExtracted texttext/plain45644${dspace.ui.url}/bitstream/11600/30535/2/WOS000255228000011.pdf.txt056905faf80d908483b41592d0b7d79aMD52open access11600/305352022-09-27 10:14:40.478open accessoai:repositorio.unifesp.br:11600/30535Repositório InstitucionalPUBhttp://www.repositorio.unifesp.br/oai/requestopendoar:34652022-09-27T13:14:40Repositório Institucional da UNIFESP - Universidade Federal de São Paulo (UNIFESP)false |
dc.title.en.fl_str_mv |
Influence of salt on the structure of DMPG studied by SAXS and optical microscopy |
title |
Influence of salt on the structure of DMPG studied by SAXS and optical microscopy |
spellingShingle |
Influence of salt on the structure of DMPG studied by SAXS and optical microscopy Fernandez, Roberto Morato gel-fluid phase transition intermediate phase charged phospholipid DLVO theory |
title_short |
Influence of salt on the structure of DMPG studied by SAXS and optical microscopy |
title_full |
Influence of salt on the structure of DMPG studied by SAXS and optical microscopy |
title_fullStr |
Influence of salt on the structure of DMPG studied by SAXS and optical microscopy |
title_full_unstemmed |
Influence of salt on the structure of DMPG studied by SAXS and optical microscopy |
title_sort |
Influence of salt on the structure of DMPG studied by SAXS and optical microscopy |
author |
Fernandez, Roberto Morato |
author_facet |
Fernandez, Roberto Morato Riske, Karin do Amaral [UNIFESP] Amaral, Lia Queiroz do Itri, Rosangela Lamy, Maria Teresa Moura |
author_role |
author |
author2 |
Riske, Karin do Amaral [UNIFESP] Amaral, Lia Queiroz do Itri, Rosangela Lamy, Maria Teresa Moura |
author2_role |
author author author author |
dc.contributor.institution.none.fl_str_mv |
Universidade Federal de São Paulo (UNIFESP) |
dc.contributor.author.fl_str_mv |
Fernandez, Roberto Morato Riske, Karin do Amaral [UNIFESP] Amaral, Lia Queiroz do Itri, Rosangela Lamy, Maria Teresa Moura |
dc.subject.eng.fl_str_mv |
gel-fluid phase transition intermediate phase charged phospholipid DLVO theory |
topic |
gel-fluid phase transition intermediate phase charged phospholipid DLVO theory |
description |
Aqueous dispersions of 50 mM dimyristoylphosphatidylglycerol (DMPG) in the presence of increasing salt concentrations (2-500 mM NaCl) were studied by small angle X-ray scattering (SAXS) and optical microscopy between 15 and 35 degrees C. SAXS data show the presence of a broad peak around q similar to 0.12 angstrom(-1) at all temperatures and conditions, arising from the electron density contrasts within the bilayer. Up to 100 mM NaCl, this broad peak is the main feature observed in the gel and fluid phases. At higher ionic strength (250-500 mM NaCl), an incipient lamellar repeat distance around d= 90-100 angstrom is detected superimposed to the bilayer form factor. the data with high salt were fit and showed that the emergent Bragg peak is due to loose multilamellar structures, with the local order vanishing after similar to 4d. Optical microscopy revealed that up to 20 mM NaCl, DMPG is arranged in submicroscopic vesicles. Giant (loose) multilamellar vesicles (MLVs) start to appear with 50 mM NaCl, although most lipids are arranged in small vesicles. As the ionic strength increases, more and denser MLVs are seen, up to 500 mM NaCl, when MLVs are the prevailing structure. the DLVO theory could account for the experimentally found interbilayer distances. (c) 2007 Elsevier B.V. All rights reserved. |
publishDate |
2008 |
dc.date.issued.fl_str_mv |
2008-04-01 |
dc.date.accessioned.fl_str_mv |
2016-01-24T13:49:40Z |
dc.date.available.fl_str_mv |
2016-01-24T13:49:40Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.citation.fl_str_mv |
Biochimica Et Biophysica Acta-biomembranes. Amsterdam: Elsevier B.V., v. 1778, n. 4, p. 907-916, 2008. |
dc.identifier.uri.fl_str_mv |
http://repositorio.unifesp.br/handle/11600/30535 http://dx.doi.org/10.1016/j.bbamem.2007.12.005 |
dc.identifier.issn.none.fl_str_mv |
0005-2736 |
dc.identifier.file.none.fl_str_mv |
WOS000255228000011.pdf |
dc.identifier.doi.none.fl_str_mv |
10.1016/j.bbamem.2007.12.005 |
dc.identifier.wos.none.fl_str_mv |
WOS:000255228000011 |
identifier_str_mv |
Biochimica Et Biophysica Acta-biomembranes. Amsterdam: Elsevier B.V., v. 1778, n. 4, p. 907-916, 2008. 0005-2736 WOS000255228000011.pdf 10.1016/j.bbamem.2007.12.005 WOS:000255228000011 |
url |
http://repositorio.unifesp.br/handle/11600/30535 http://dx.doi.org/10.1016/j.bbamem.2007.12.005 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.ispartof.none.fl_str_mv |
Biochimica Et Biophysica Acta-biomembranes |
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http://www.elsevier.com/about/open-access/open-access-policies/article-posting-policy info:eu-repo/semantics/openAccess |
rights_invalid_str_mv |
http://www.elsevier.com/about/open-access/open-access-policies/article-posting-policy |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
907-916 |
dc.publisher.none.fl_str_mv |
Elsevier B.V. |
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Elsevier B.V. |
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