Croconaine and squaraine dyes: their role as photosensitizers in antimicrobial photodynamic therapy
Autor(a) principal: | |
---|---|
Data de Publicação: | 2021 |
Tipo de documento: | Dissertação |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10348/11009 |
Resumo: | Wounds represent a location in the organism of possible bacteria contamination. These are part of the skin's natural microbiota, but in reduced quantities. A high concentration of bacteria on the wound location can lead to the development of chronic wounds or infections. In the past few years, the excessive use of antibiotics has led to the development of several bacterial multirresistance mechanisms, which means it is necessary to develop alternative therapies in hopes to ease this problematic. Bacterial multiresistance limits treatment options against bacteria, which possess a high epidemic dissemination capacity that can lead to serious infections. In this study, croconaine and squaraine dyes were synthesized, spectroscopically characterized and their phototherapeutic effect was studied when irradiating bacteria together with dye solutions (640 nm and 700 nm, with concentrations of 0.01, 0.1, 1, 2.5 and 10 µM) to evaluate their antibacterial ability. The bacteria used in this study originated from polymicrobial infections from two patients from different CHTMAD (Centro Hospitalar de Trás-os-Montes e Alto Douro) services, posteriorly catalogued to the MJMC collection (588, 589, 590, 602, 603, 604). Two different control bacteria were used: an S. aureus CECT 976 and an E. coli CECT 434; a Gram-positive and a Gramnegative bacterium, respectively. The studied bacteria showed a typical behavior for Gram-positive and Gramnegative bacteria, whereas the first ones showed a higher dye permeability through their cell wall. This permeability can be enhanced by adding agents that could favor the disruption of their cell walls. The synthesized dyes showed a satisfactory level of purity. However, these showed to be difficult to synthesized due to the necessary care during the synthesis process. The obtained results revealed that the synthesized dyes showed some antimicrobial photoinactivation potential, which can be improved with structural changes, enhancing their phototherapeutic effect. |
id |
RCAP_5b98a20fb2428d0c0775b70b574a2a83 |
---|---|
oai_identifier_str |
oai:repositorio.utad.pt:10348/11009 |
network_acronym_str |
RCAP |
network_name_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository_id_str |
7160 |
spelling |
Croconaine and squaraine dyes: their role as photosensitizers in antimicrobial photodynamic therapyAntimicrobial photodynamic therapysquaraine dyesWounds represent a location in the organism of possible bacteria contamination. These are part of the skin's natural microbiota, but in reduced quantities. A high concentration of bacteria on the wound location can lead to the development of chronic wounds or infections. In the past few years, the excessive use of antibiotics has led to the development of several bacterial multirresistance mechanisms, which means it is necessary to develop alternative therapies in hopes to ease this problematic. Bacterial multiresistance limits treatment options against bacteria, which possess a high epidemic dissemination capacity that can lead to serious infections. In this study, croconaine and squaraine dyes were synthesized, spectroscopically characterized and their phototherapeutic effect was studied when irradiating bacteria together with dye solutions (640 nm and 700 nm, with concentrations of 0.01, 0.1, 1, 2.5 and 10 µM) to evaluate their antibacterial ability. The bacteria used in this study originated from polymicrobial infections from two patients from different CHTMAD (Centro Hospitalar de Trás-os-Montes e Alto Douro) services, posteriorly catalogued to the MJMC collection (588, 589, 590, 602, 603, 604). Two different control bacteria were used: an S. aureus CECT 976 and an E. coli CECT 434; a Gram-positive and a Gramnegative bacterium, respectively. The studied bacteria showed a typical behavior for Gram-positive and Gramnegative bacteria, whereas the first ones showed a higher dye permeability through their cell wall. This permeability can be enhanced by adding agents that could favor the disruption of their cell walls. The synthesized dyes showed a satisfactory level of purity. However, these showed to be difficult to synthesized due to the necessary care during the synthesis process. The obtained results revealed that the synthesized dyes showed some antimicrobial photoinactivation potential, which can be improved with structural changes, enhancing their phototherapeutic effect.As feridas representam no organismo um local para possíveis contaminações de bactérias. Estas fazem parte da microbiota natural da pele, mas em pequenas quantidades. Uma elevada concentração de bactérias no local da ferida pode levar ao desenvolvimento de feridas crónicas ou infeções. Nos últimos anos, o uso excessivo de antibióticos levou ao desenvolvimento de vários mecanismos de multirresistência bacteriana, o que tem levado ao desenvolvimento de várias terapias alternativas com esperança em minimizar esta problemática. A multirresistência bacteriana limita as opções de tratamento contra as bactérias, possuindo uma grande capacidade de disseminação que pode levar a infeções sérias. Neste estudo, foram sintetizados corantes crocónicos e esquarílicos, caracterizados espetroscopicamente e o seu efeito fototerapêutico foi estudado ao irradiar bactérias em conjunto com soluções dos corantes (a 640 nm e a 700 nm, com concentrações de 0,01; 0,1; 1; 2,5 e 10 µM) para avaliar a sua capacidade antibacteriana. As bactérias utilizadas neste estudo tiveram origem em infeções polimicrobianas de dois pacientes de diferentes serviços do CHTMAD (Centro Hospitalar de Trás-os-Montes e Alto Douro), catalogadas posteriormente na coleção MJMC (588, 589, 590, 602, 603, 604). Duas bactérias controlo foram utilizadas: uma S. aureus CECT 976 e uma E. coli CECT 434; uma bactéria Gram-positivo e uma bactéria Gram-negativo, respetivamente. As bactérias estudadas apresentaram um comportamento típico para bactérias Gram positivo e Gram negativo, sendo que as primeiras mostraram uma maior permeabilização dos corantes pela sua parede celular. Esta permeabilização poderá ser melhorada com a adição de agentes que favoreçam o rompimento das paredes celulares. Os corantes sintetizados apresentaram um grau satisfatório de pureza. Contudo, estes mostraram-se ser difíceis de sintetizar devido aos cuidados necessários durante o processo de sintetização. Os resultados obtidos revelaram que os corantes sintetizados demonstraram um algum potencial de fotoinativação antimicrobiana que poderão ser melhorados com alterações estruturais, de forma a potenciar o seu efeito fototerapêutico.2022-01-28T15:09:28Z2021-09-30T00:00:00Z2021-09-30info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisapplication/pdfapplication/pdfapplication/pdfhttp://hdl.handle.net/10348/11009engmetadata only accessinfo:eu-repo/semantics/openAccessMartins, Brunoreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2024-02-02T12:48:32Zoai:repositorio.utad.pt:10348/11009Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-20T02:04:38.975145Repositório 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 |
Croconaine and squaraine dyes: their role as photosensitizers in antimicrobial photodynamic therapy |
title |
Croconaine and squaraine dyes: their role as photosensitizers in antimicrobial photodynamic therapy |
spellingShingle |
Croconaine and squaraine dyes: their role as photosensitizers in antimicrobial photodynamic therapy Martins, Bruno Antimicrobial photodynamic therapy squaraine dyes |
title_short |
Croconaine and squaraine dyes: their role as photosensitizers in antimicrobial photodynamic therapy |
title_full |
Croconaine and squaraine dyes: their role as photosensitizers in antimicrobial photodynamic therapy |
title_fullStr |
Croconaine and squaraine dyes: their role as photosensitizers in antimicrobial photodynamic therapy |
title_full_unstemmed |
Croconaine and squaraine dyes: their role as photosensitizers in antimicrobial photodynamic therapy |
title_sort |
Croconaine and squaraine dyes: their role as photosensitizers in antimicrobial photodynamic therapy |
author |
Martins, Bruno |
author_facet |
Martins, Bruno |
author_role |
author |
dc.contributor.author.fl_str_mv |
Martins, Bruno |
dc.subject.por.fl_str_mv |
Antimicrobial photodynamic therapy squaraine dyes |
topic |
Antimicrobial photodynamic therapy squaraine dyes |
description |
Wounds represent a location in the organism of possible bacteria contamination. These are part of the skin's natural microbiota, but in reduced quantities. A high concentration of bacteria on the wound location can lead to the development of chronic wounds or infections. In the past few years, the excessive use of antibiotics has led to the development of several bacterial multirresistance mechanisms, which means it is necessary to develop alternative therapies in hopes to ease this problematic. Bacterial multiresistance limits treatment options against bacteria, which possess a high epidemic dissemination capacity that can lead to serious infections. In this study, croconaine and squaraine dyes were synthesized, spectroscopically characterized and their phototherapeutic effect was studied when irradiating bacteria together with dye solutions (640 nm and 700 nm, with concentrations of 0.01, 0.1, 1, 2.5 and 10 µM) to evaluate their antibacterial ability. The bacteria used in this study originated from polymicrobial infections from two patients from different CHTMAD (Centro Hospitalar de Trás-os-Montes e Alto Douro) services, posteriorly catalogued to the MJMC collection (588, 589, 590, 602, 603, 604). Two different control bacteria were used: an S. aureus CECT 976 and an E. coli CECT 434; a Gram-positive and a Gramnegative bacterium, respectively. The studied bacteria showed a typical behavior for Gram-positive and Gramnegative bacteria, whereas the first ones showed a higher dye permeability through their cell wall. This permeability can be enhanced by adding agents that could favor the disruption of their cell walls. The synthesized dyes showed a satisfactory level of purity. However, these showed to be difficult to synthesized due to the necessary care during the synthesis process. The obtained results revealed that the synthesized dyes showed some antimicrobial photoinactivation potential, which can be improved with structural changes, enhancing their phototherapeutic effect. |
publishDate |
2021 |
dc.date.none.fl_str_mv |
2021-09-30T00:00:00Z 2021-09-30 2022-01-28T15:09:28Z |
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/10348/11009 |
url |
http://hdl.handle.net/10348/11009 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.rights.driver.fl_str_mv |
metadata only access info:eu-repo/semantics/openAccess |
rights_invalid_str_mv |
metadata only access |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf application/pdf application/pdf |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
instname_str |
Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
instacron_str |
RCAAP |
institution |
RCAAP |
reponame_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
collection |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository.name.fl_str_mv |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
repository.mail.fl_str_mv |
|
_version_ |
1799137132691849216 |