Exchange dynamics between amphiphilic block copolymers and lipidic membranes through hydrophobic pyrene probe transfer

Abstract

Exchange dynamics between P104 micelles and liposomes for vectorization followed by using PyC18 hydrophobic probe.

Structural Behavior of Amphiphilic Triblock Copolymer P104/Water System

“…The low scattered light intensity observed at temperatures below 26 • C is directly related to the presence of P104 unimers in the solution [60]. Therefore, the temperature of 26 • C is related to the CMT of P104 triblock copolymer at 1 wt.%, which is in good agreement with the CMT value reported in the literature for a P104/water system evaluated at the same concentration [2,11]. After the appearance of the CMT, while increasing the temperature, the scattered light intensity also increases and remains almost constant in the following temperature range: from 26 to 54 • C, though, after 55 • C, the progressive increase of I SCA until reaching a twomagnitude order difference from the initial value suggests the appearance of a new P104 structure.…”

“…The obtained micellar structure for P104 amphiphilic copolymer in water in the temperature range between 25 and 55 • C, corresponding to the spherical micelle domain, is suitable to be used a micellar nanocarrier for drug-controlled release and their dynamics are now being studied with lipidic membranes through hydrophobic pyrene probe transfer [11]. Their nanoscale size makes them a suitable option for targeted drug delivery applications, including storage, controlled release, and protection of the hydrophobic drugs [94].…”

“…Amphiphilic triblock copolymers, also known by their commercial name Pluronic ® , consisting of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) blocks as follows: PEO x -PPO y -PEO x , have been studied due to their efficiency during drug delivery processes [7][8][9][10]. Drug incorporation into the micelle core formed by these amphiphilic block copolymers can provide metabolic stability, superior drug circulation time, and an increment of solubility [9,11]. Therefore, micelle core-shell structure and characteristics are essential for their efficiency in drug delivery [12].…”

“…Therefore, micelle core-shell structure and characteristics are essential for their efficiency in drug delivery [12]. This core is also a compartment incompatible with water but is able to store different kinds of therapeutic reagents [11,13]. Gene delivery is another pharmaceutical application that has been proposed for several block copolymers [9,[14][15][16][17].…”

“…Scattering and rheology studies on micellar characteristics of P104 in the presence of anthranilic acid (AA) revealed important variations by changing the pH solution [70]. Furthermore, P104 has also been used in the study of dynamics between Pluronic micelles and liposomes for the vectorization of hydrophobic molecules using a fluorescence technique [11]. The exchange dynamics between both of them, studied at different liposome concentrations, were demonstrated to be a collective mechanism characterized by presenting two rate constants: one rate independent of liposome concentration and the second one with dynamics linearly dependent on liposomes concentration [11].…”