Temperature-controlled content release from liposomes encapsulating Pluronic F127

Area of Science:

• Lipid bilayer dynamics and drug delivery systems.
• Nanotechnology and materials science applications.

Background:

• Liposomes are widely used drug delivery vehicles.
• Controlling drug release from liposomes is crucial for therapeutic efficacy.
• Temperature-sensitive liposomes offer tunable release profiles.

Purpose of the Study:

• To investigate temperature-dependent content release from liposomes.
• To understand the role of Pluronic F127 and cholesterol in liposome destabilization.
• To characterize the influence of encapsulated molecule size on release kinetics.

Main Methods:

• Utilized di-oleoylphosphatidylcholine (DOPC)/cholesterol liposomes encapsulating Pluronic F127.
• Employed fluorescent markers (carboxyfluorescein and BSA-FITC) to quantify content release.
• Measured release via fluorescence de-quenching and FRET-based quenching.
• Investigated the effect of Pluronic concentration, cholesterol content, and marker size.

Main Results:

• Pluronic F127 interaction with lipid bilayers at elevated temperatures triggers content release.
• Cholesterol increased the sharpness of temperature-dependent release.
• Onset temperature of release correlated with Pluronic concentration and marker size.
• Release onset temperature is linked to the critical micellar temperature (CMT) of Pluronic F127.
• Stealth liposomes (DSPEG5000PE) exhibited comparable temperature sensitivity.

Conclusions:

• Pluronic F127 concentration and liposome composition (cholesterol) enable precise control over temperature-triggered content release.
• Encapsulated molecule size influences the onset temperature of release.
• This study establishes a foundation for developing advanced temperature-sensitive drug delivery systems.