pH-sensitive liposomes containing polymerized phosphatidylethanolamine and fatty acid

Area of Science:

• Biomaterials Science
• Nanotechnology
• Drug Delivery Systems

Background:

• Targeting cancer drugs to malignant tissues is crucial for improving treatment efficacy and reducing side effects.
• Liposomes are promising drug delivery vehicles, but their stability and targeted release require optimization.

Purpose of the Study:

• To prepare and characterize pH-sensitive polymeric liposomes for targeted cancer drug delivery.
• To investigate the influence of composition on liposome stability and pH-responsiveness.
• To evaluate the effect of plasma components on liposome stability.

Main Methods:

• Synthesis of diacetylenic phosphatidylethanolamine (DAPE).
• Preparation of liposomes incorporating DAPE, fatty acids, and either phosphatidylethanolamine (PE) or phosphatidylethanolamine-beta-oleoyl-gamma-palmitoyl (POPE).
• Polymerization of DAPE using UV illumination.
• Assessment of liposome stability at physiological and acidic pH.
• Evaluation of liposome interactions with blood plasma albumin, apolipoprotein A-I, and whole plasma.

Main Results:

• Polymeric liposomes were successfully prepared and demonstrated stability at physiological pH.
• Liposomes exhibited pH-sensitivity, becoming leaky below pH 6.5.
• Optimal pH-sensitivity was achieved with liposomes containing 35 mol% DAPE, 35 mol% POPE, and 30% saturated fatty acid.
• Blood plasma albumin decreased vesicle stability, while apolipoprotein A-I and whole plasma showed stabilizing effects.

Conclusions:

• pH-sensitive polymeric liposomes can be engineered for targeted drug delivery.
• Liposome composition significantly influences pH-responsiveness and stability.
• These findings support the potential of DAPE-containing liposomes for cancer therapy applications.