Two dimensional layered double hydroxides augment antigen loading and release

Area of Science:

• Materials Science
• Nanotechnology
• Biomedical Engineering

Background:

• Layered double hydroxides (LDHs) are nanoscale anionic clays with potential in medicine.
• Their layered structure and positive surface charge make them suitable for biomolecule delivery.
• The influence of LDH metal composition on protein delivery remains largely unexplored.

Purpose of the Study:

• To investigate how different LDH metal compositions affect protein encapsulation, cellular uptake, and release kinetics.
• To compare the performance of various LDHs with the commercial adjuvant alum.
• To identify optimal LDH formulations for enhanced drug delivery applications.

Main Methods:

• Synthesized eight different LDHs using coprecipitation and hydrothermal methods.
• Loaded LDHs with ovalbumin (OVA) and compared encapsulation efficiency with alum.
• Assessed cellular uptake of LDH-OVA complexes in MCF-7 breast cancer cells and spleen cells.
• Monitored OVA release kinetics from LDHs and alum over 48 hours.

Main Results:

• ZnAl and MgAl LDHs demonstrated over 80% OVA encapsulation efficiency.
• ZnAl LDHs exhibited a ~15% higher OVA-loading capacity compared to alum.
• LDH-OVA complexes showed significantly faster and greater cellular uptake than OVA or OVA-alum.
• LDHs exhibited sustained OVA release (54-65% over 48h) compared to alum (82% over 48h).

Conclusions:

• LDH metal composition critically influences protein delivery characteristics.
• ZnAl and MgAl LDHs serve as effective nanocarriers for protein delivery, enhancing encapsulation and cellular uptake.
• LDHs provide a sustained release profile, suggesting potential for improved therapeutic efficacy compared to alum.