A closer look into laurdan as a probe to monitor cationic DODAB bilayers

Autor(es)

Masukawa, Marcos K. ^{[1, 2]} ; Vequi-Suplicy, Cintia C. ^{[1, 3]} ; Duarte, Evandro L. ^[1] ; Lamy, M. Teresa ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Fis, Sao Paulo - Brazil

^[2] Tokyo Inst Technol, Room 1710, Bldg J2, Suzukake Dai Campus, Yokohama, Kanagawa - Japan

^[3] Fdn IMDEA Nanociencia Cantoblanco, C Faraday 9, Madrid 28049 - Spain

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY; v. 376, p. 238-246, MAY 1 2019.
• Citações Web of Science: 0

Resumo

Laurdan is a fluorescent molecule largely used to probe the lipid packing and hydration of membranes. In phospholipid bilayers that undergo the gel-fluid thermal transition, Laurdan fluorescent band displays a significant red shift upon the transition. However, Laurdan in DODAB bilayers does not show this characteristic shift of the emission band. Hence, the analysis of the membrane fluidity through the so-called Generalized Polarization (GP) cannot be used with DODAB. Nevertheless, both static and time resolved fluorescence attest that the Laurdan fluorescence in DODAB, like in phospholipids, is composed of two emission bands. The emission bands are associated with excited states with different lifetimes, and the relative intensity of the bands is sensitive to the bilayer thermal phase. Analyses were performed by decomposing the emission spectrum into two Gaussian bands and by computing the Decay Associated Spectra (DAS), the latter with time resolved fluorescence. We conclude that Laurdan in DODAB bilayers is in a shallower position as compared with the probe in phospholipids, possibly due to the small DODAB head group. Hence, Laurdan could be a useful probe to monitor interactions at the surface of DODAB bilayers, for instance with genetic material, quite often associated with cationic vesicles in lipoplexes, with broad medical applications. (AU)

• Processo FAPESP: 06/55513-9 - Estudos experimentais e teóricos dos espectros eletrônicos das sondas fluorescentes Prodan e Laurdan em solventes e bicamadas lipídicas
• Beneficiário: Cíntia Cristina De Vequi Suplicy
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 05/52408-7 - Hidratação e estrutura de membranas lipídicas na fase fluida: um estudo comparativo com sondas fluorescentes e paramagnéticas
• Beneficiário: Cíntia Cristina De Vequi Suplicy
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 13/24949-0 - Caracterização estrutural de agregados anfifílicos catiônicos: um estudo com a sonda fluorescente Laurdan
• Beneficiário: Marcos Kunihiro Masukawa
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 10/08365-0 - Estudo Teórico de Nucleosídeos Lipofílicos em Solventes e em Monocamadas Lipídicas Utilizando Métodos Híbridos de Mecânica Quântica e Mecânica Molecular.
• Beneficiário: Cíntia Cristina De Vequi Suplicy
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 13/14419-3 - Dispersões aquosas de agregados anfifílicos de interesse biológico: estudo de estruturas e interações
• Beneficiário: Maria Teresa Moura Lamy
• Modalidade de apoio: Auxílio à Pesquisa - Regular