Nanoparticles as a tool in capillary electrochromatography
Autor(a) principal: | |
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Data de Publicação: | 2009 |
Tipo de documento: | Dissertação |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10400.6/1341 |
Resumo: | Two different types of molecularly imprinted nanoparticles against (R)-propranolol were used to separate the enantiomers of propranolol in capillary electrochromatography mode, methacrylic acid based nanoparticles and core-shell molecularly imprinted polymer nanoparticles. Partial filling technique was used to avoid interference of molecularly imprinted polymer nanoparticles in UV detection. With methacrylic acid based nanoparticles it was not possible to obtain enantiomer separation. Strong unspecific interactions between the molecular imprinted polymer nanoparticles and propranolol disturbed enantiomer separation. Since large content of acetonitrile had to be used in order to obtain stable suspensions of molecularly imprinted polymer nanoparticles, the electrostatic interactions were favored which contributed to the unspecific interactions occurring. Core-shell molecularly imprinted polymer nanoparticles present suspension stability at low content of acetonitrile due to the poly(acrylamide) shell that makes them more hydrophilic. Enantiomer separation of propranolol was achieved with 40% of acetonitrile. Reproducibility was problematic due to the unspecific interactions occurring. With time several factors can occur contributing to the decreased reproducibility of results such as, interactions between the molecularly imprinted polymer nanoparticles and the capillary wall or evaporation of the organic solvent due to the design of vials used in capillary electrochromatography system. The core-shell molecularly imprinted polymer nanoparticles are more suitable for propranolol enantiomer separation in comparison to methacrylic acid based nanoparticles. More stable suspensions give a greater range of conditions that can be tested. Silanized gadolinium oxide nanoparticles were tested as pseudostationary phase in capillary electrochromatography for protein separation. The lack of interference with UV detection and the large surface area of these nanoparticles make them a promising tool in capillary electrochromatography for protein separation. These nanoparticles interact with the proteins that are analyzed. Increased injection times of the nanoparticles give retained peaks of human growth hormone showing that strong interactions between the protein and nanoparticles are occurring. Lysozyme that was not recovered using conventional capillary electrophoresis could be detected when nanoparticles were used as pseudostationary phase. The nanoparticles can act as a coating in the capillary wall or due to their large surface area they can prevent adsorption of the lysozyme to the capillary. |
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Nanoparticles as a tool in capillary electrochromatographyElectrocromatografia capilarNanopartículas - PropranololNanopartículas - LisozimaNanopartículas - ProteínasMiniaturizaçãoDomínio/Área Científica::Engenharia e Tecnologia::Engenharia QuímicaTwo different types of molecularly imprinted nanoparticles against (R)-propranolol were used to separate the enantiomers of propranolol in capillary electrochromatography mode, methacrylic acid based nanoparticles and core-shell molecularly imprinted polymer nanoparticles. Partial filling technique was used to avoid interference of molecularly imprinted polymer nanoparticles in UV detection. With methacrylic acid based nanoparticles it was not possible to obtain enantiomer separation. Strong unspecific interactions between the molecular imprinted polymer nanoparticles and propranolol disturbed enantiomer separation. Since large content of acetonitrile had to be used in order to obtain stable suspensions of molecularly imprinted polymer nanoparticles, the electrostatic interactions were favored which contributed to the unspecific interactions occurring. Core-shell molecularly imprinted polymer nanoparticles present suspension stability at low content of acetonitrile due to the poly(acrylamide) shell that makes them more hydrophilic. Enantiomer separation of propranolol was achieved with 40% of acetonitrile. Reproducibility was problematic due to the unspecific interactions occurring. With time several factors can occur contributing to the decreased reproducibility of results such as, interactions between the molecularly imprinted polymer nanoparticles and the capillary wall or evaporation of the organic solvent due to the design of vials used in capillary electrochromatography system. The core-shell molecularly imprinted polymer nanoparticles are more suitable for propranolol enantiomer separation in comparison to methacrylic acid based nanoparticles. More stable suspensions give a greater range of conditions that can be tested. Silanized gadolinium oxide nanoparticles were tested as pseudostationary phase in capillary electrochromatography for protein separation. The lack of interference with UV detection and the large surface area of these nanoparticles make them a promising tool in capillary electrochromatography for protein separation. These nanoparticles interact with the proteins that are analyzed. Increased injection times of the nanoparticles give retained peaks of human growth hormone showing that strong interactions between the protein and nanoparticles are occurring. Lysozyme that was not recovered using conventional capillary electrophoresis could be detected when nanoparticles were used as pseudostationary phase. The nanoparticles can act as a coating in the capillary wall or due to their large surface area they can prevent adsorption of the lysozyme to the capillary.Dois tipos diferentes de nanopartículas impressas molecularmente, selectivas de (R) – propranolol, foram utilizadas para a separação dos enantiomeros de propranolol em electrocromatografia capilar ( nanopartículas à base de ácido metacrílico e nanopartículas revestidas com poliacrilamida). Para evitar interferência das nanopartículas com a detecção UV a técnica de preenchimento parcial foi utilizada. Com as nanopartículas à base de ácido metacrílico a separação dos enantiomeros de propranolol não foi alcançada. Interacções fortes inespecíficas entre as nanopartículas e o propronolol impossibilitaram a separação. Para obter suspensões estáveis de nanopartículas à base de ácido metacrílico elevadas quantidades de acetonitrilo foram utilizadas, favorecendo interacções eletrostáticas que contribuiram para o aumento das interacções inespecíficas. As nanopartículas revestidas com poliacrilamida apresentam suspensões estáveis com baixas quantidades de acetonitrilo, devido as propriedades hidrofílicas da poliacrilamida. A separação dos enantiomeros de propranolol foi alcançada com 40% de acetonitrilo. As interacções inespecíficas foram um factor dominante na irreproducibilidade dos resultados. Com o tempo vários factores contribuem para a diminuição da reproducibilidade dos resultados como por exemplo: interacções entre as nanopartículas e a parede do capilar e a evaporação do solvente orgânico devido ao design dos tubos de ensaio utilizados na electrocromatografia capilar. As nanopartículas revestidas com poliacrilamida säo mais adequadas para a separação dos enantiomeros de propranolol devido á elevada estabilidade de suspensöes apresentada em diferentes condições. Nanopartículas de gadolínio silanizadas foram testadas como fase pseudoestacionária em electrocromatografia capilar. Características como a não detecção em UV e a grande área de superfície tornam estas nanopartículas de grande interesse para a separação de proteínas. A hormona de crescimento e a lisozima foram as proteínas analisadas. A hormona de crescimento apresenta picos mais retidos quando se aumenta os tempos de injecção das nanopartículas, mostrando que interacções entre a proteína e as nanopartículas ocorrem. A utilização destas nanopartículas como fase pseudoestacionária permitiu a detecção da lisozima que não é visível utilizando electroforese capilar convencional. A adsorção da lisozima à parede do capilar é evitada devido ao uso destas nanopartículas.Nilsson, StaffanTomaz, Cândida Ascensão TeixeirauBibliorumChaves, Susana Isabel Ribeiro2013-09-25T15:09:49Z20092009-01-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisapplication/pdfhttp://hdl.handle.net/10400.6/1341enginfo:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2023-12-15T09:36:54Zoai:ubibliorum.ubi.pt:10400.6/1341Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-20T00:43:12.218302Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Nanoparticles as a tool in capillary electrochromatography |
title |
Nanoparticles as a tool in capillary electrochromatography |
spellingShingle |
Nanoparticles as a tool in capillary electrochromatography Chaves, Susana Isabel Ribeiro Electrocromatografia capilar Nanopartículas - Propranolol Nanopartículas - Lisozima Nanopartículas - Proteínas Miniaturização Domínio/Área Científica::Engenharia e Tecnologia::Engenharia Química |
title_short |
Nanoparticles as a tool in capillary electrochromatography |
title_full |
Nanoparticles as a tool in capillary electrochromatography |
title_fullStr |
Nanoparticles as a tool in capillary electrochromatography |
title_full_unstemmed |
Nanoparticles as a tool in capillary electrochromatography |
title_sort |
Nanoparticles as a tool in capillary electrochromatography |
author |
Chaves, Susana Isabel Ribeiro |
author_facet |
Chaves, Susana Isabel Ribeiro |
author_role |
author |
dc.contributor.none.fl_str_mv |
Nilsson, Staffan Tomaz, Cândida Ascensão Teixeira uBibliorum |
dc.contributor.author.fl_str_mv |
Chaves, Susana Isabel Ribeiro |
dc.subject.por.fl_str_mv |
Electrocromatografia capilar Nanopartículas - Propranolol Nanopartículas - Lisozima Nanopartículas - Proteínas Miniaturização Domínio/Área Científica::Engenharia e Tecnologia::Engenharia Química |
topic |
Electrocromatografia capilar Nanopartículas - Propranolol Nanopartículas - Lisozima Nanopartículas - Proteínas Miniaturização Domínio/Área Científica::Engenharia e Tecnologia::Engenharia Química |
description |
Two different types of molecularly imprinted nanoparticles against (R)-propranolol were used to separate the enantiomers of propranolol in capillary electrochromatography mode, methacrylic acid based nanoparticles and core-shell molecularly imprinted polymer nanoparticles. Partial filling technique was used to avoid interference of molecularly imprinted polymer nanoparticles in UV detection. With methacrylic acid based nanoparticles it was not possible to obtain enantiomer separation. Strong unspecific interactions between the molecular imprinted polymer nanoparticles and propranolol disturbed enantiomer separation. Since large content of acetonitrile had to be used in order to obtain stable suspensions of molecularly imprinted polymer nanoparticles, the electrostatic interactions were favored which contributed to the unspecific interactions occurring. Core-shell molecularly imprinted polymer nanoparticles present suspension stability at low content of acetonitrile due to the poly(acrylamide) shell that makes them more hydrophilic. Enantiomer separation of propranolol was achieved with 40% of acetonitrile. Reproducibility was problematic due to the unspecific interactions occurring. With time several factors can occur contributing to the decreased reproducibility of results such as, interactions between the molecularly imprinted polymer nanoparticles and the capillary wall or evaporation of the organic solvent due to the design of vials used in capillary electrochromatography system. The core-shell molecularly imprinted polymer nanoparticles are more suitable for propranolol enantiomer separation in comparison to methacrylic acid based nanoparticles. More stable suspensions give a greater range of conditions that can be tested. Silanized gadolinium oxide nanoparticles were tested as pseudostationary phase in capillary electrochromatography for protein separation. The lack of interference with UV detection and the large surface area of these nanoparticles make them a promising tool in capillary electrochromatography for protein separation. These nanoparticles interact with the proteins that are analyzed. Increased injection times of the nanoparticles give retained peaks of human growth hormone showing that strong interactions between the protein and nanoparticles are occurring. Lysozyme that was not recovered using conventional capillary electrophoresis could be detected when nanoparticles were used as pseudostationary phase. The nanoparticles can act as a coating in the capillary wall or due to their large surface area they can prevent adsorption of the lysozyme to the capillary. |
publishDate |
2009 |
dc.date.none.fl_str_mv |
2009 2009-01-01T00:00:00Z 2013-09-25T15:09:49Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/masterThesis |
format |
masterThesis |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/10400.6/1341 |
url |
http://hdl.handle.net/10400.6/1341 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.source.none.fl_str_mv |
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Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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RCAAP |
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RCAAP |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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