The Role of Pectin in Optimizing Cationic Liposomes for Oral Delivery

Area of Science:

• Pharmaceutical Sciences
• Biomaterials Science
• Drug Delivery

Background:

• Liposomes are crucial for drug and vaccine delivery but face stability challenges in the gastrointestinal tract, hindering oral administration.
• Optimizing liposomes for oral delivery requires strategies to enhance their stability and ensure effective mucosal interaction.

Purpose of the Study:

• To investigate the potential of pectin-coated cationic liposomes for enhanced mucosal delivery.
• To evaluate the impact of different pectin types (LM, LMA, HM) on liposome stability, mucin interaction, and cellular uptake.

Main Methods:

• Coating cationic adjuvant formulation (CAF04) liposomes with low methoxylated (LM), low methoxylated amidated (LMA), or high methoxylated (HM) pectins.
• Assessing *in vitro* stability in simulated intestinal fluid, mucin interaction, and diffusivity across artificial mucus.
• Evaluating *in situ* intestinal retention in rats and macrophage-like cell uptake.

Main Results:

• Pectin coatings significantly improved liposome stability against premature degradation in simulated intestinal fluid.
• LM and LMA-pectin coatings provided a protective buffer, preventing excessive mucin complexation.
• Pectin-coated liposomes exhibited retained intestinal presence and did not impede macrophage uptake, indicating preserved functionality.

Conclusions:

• Pectins are effective excipients for developing stable mucosal delivery systems, particularly for oral liposome-based vaccines.
• Pectin coatings mitigate undesirable interactions with bile salts and mucins while maintaining cellular uptake efficiency.
• This study highlights pectin-coated liposomes as a promising strategy for oral mucosal delivery applications.