The prodan photophysics as a tool to determine the bilayer properties of different unilamellar vesicles composed of phospholipids

LUNA, ALEJANDRA; GIRARDI, VALERIA; SANCHEZ CERVIÑO, M. CELINA; RIVERO GUADALUPE; FALCONE, DARÍO; MOYANO, FERNANDO; CORREA, NÉSTOR MARIANO

LANGMUIR

AMER CHEMICAL SOC

Lugar: Washington; Año: 2023 vol. 40 p. 657 - 667

0743-7463

Vesicles formed by phospholipids are promising candidates for drug delivery. It is known that lipid composition affects properties such as rigidity-fluidity of the membrane and that it influences the bilayer permeability but sometimes sophisticated techniques are selected to monitor them. In this work, we study the bilayer of different unilamellar vesicles composed of different lipids (1,2-dioleoyl-sn-glycero-3-phosphocholine, DOPC, and lecithin) and diverse techniques: extruder and electrospun templates, using 6-propionyl-2-(N,N-dimethyl) aminonaphthalene (PRODAN) and its photophysics. Moreover, we were able to monitor the influence of cholesterol on the bilayers. We demonstrate that the bilayer properties can be evaluated by using the emission feature of the molecular probe PRODAN. This fluorescent probe gives relevant information about the polarity and fluidity of the microenvironment, for unilamellar vesicles formed by two different methods.The PRODAN emission at 434 nm suggests that the bilayer properties significantly change if DOPC or lecithin is used in the vesicle preparation, especially in their fluidity. Moreover, cholesterol induces alterations in the bilayer´s structural and microenvironmental properties, to a greater or lesser degree, in both vesicles.Thus, we propose an easy and elegant way to evaluate physicochemical properties, which is fundamental for manufacturing vesicles as a drug delivery system, simply by monitoring the molecular probe emission band centered at 434 nm which corresponds to PRODAN species deep inside the bilayer.