Chain Cleavage of Bioinspired Bacterial Membranes Photoinduced by Eosin Decyl Ester

Author(s)

Moreira, Lucas G. ^[1] ; Almeida Jr, Alexandre M. ; Camacho, Sabrina A. ^{[2, 3]} ; Estevao, Bianca M. ^{[2, 4]} ; Oliveira Jr, Osvaldo N. ; Aoki, Pedro H. B. ^[3]

Affiliation

^[1] Sao Paulo State Univ, Sch Sci Humanities & Languages, UNESP, BR-19806900 Assis, SP - Brazil

^[2] Univ Sao Paulo, Sao Carlos Inst Phys, IFSC, BR-13566590 Sao Carlos, SP - Brazil

^[3] Almeida Jr, Jr., Alexandre M., Sao Paulo State Univ, Sch Sci Humanities & Languages, UNESP, BR-19806900 Assis, SP - Brazil

^[4] State Univ Maringa UEM, Dept Chem, BR-87020900 Maringa, Parana - Brazil

• Document type: Journal article
• Source: Langmuir; v. 36, n. 32, p. 9578-9585, AUG 18 2020.
• Web of Science Citations: 0

Abstract

Photodynamic therapy (PDT) is promising for bacterial inactivation since cellular internalization of photosensitizers (PS) is not crucial for the treatment effectiveness. Photoinduced damage in the lipid envelope may already induce microbial inactivation, which requires PS capable of easily penetrating into the membrane. Herein, we report on the insertion of the PS eosin decyl ester (EosDec) into Langmuir films of 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE), 1,2-dioleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (DOPG), and cardiolipin (CLP) used as mimetic systems of bacterial membranes. Surface pressure isotherms and polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS) indicated that the hydrophobic nature of EosDec favored deeper penetration in all the phospholipid monolayers. The incorporation of EosDec led to monolayer expansion, especially in the anionic DOPG and CLP owing to repulsive electrostatic interactions, and induced disorder in the lipid chains. Light irradiation of DOPE, DOPG, and CLP monolayers containing EosDec increased the rate of material loss to the subphase, which is attributed to cleavage of lipid chains triggered by contact-dependent reactions between excited states of EosDec and lipid unsaturations. The latter is key for membrane permeabilization and efficiency in microbial inactivation. (AU)

• FAPESP's process: 18/22214-6 - Towards a convergence of technologies: from sensing and biosensing to information visualization and machine learning for data analysis in clinical diagnosis
• Grantee: Osvaldo Novais de Oliveira Junior
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 18/14692-5 - Photothermal therapy mediated by gold nanoparticles: from model systems of biomembranes toward in vitro culture of tumor cells
• Grantee: Sabrina Aléssio Camacho
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 13/14262-7 - Nanostructured films from biologically-relevant materials
• Grantee: Osvaldo Novais de Oliveira Junior
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 18/13021-0 - Photo-oxidation of Langmuir films as mimetic systems of Escherichia coli membrane
• Grantee: Lucas Gontijo Moreira
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 18/16713-0 - Photodynamic therapy: from molecular effects in model systems toward photodynamic efficiency in cell culture
• Grantee: Pedro Henrique Benites Aoki
• Support Opportunities: Regular Research Grants