Insights into gold nanoparticles as a mucoadhesive system

Area of Science:

• Nanotechnology
• Materials Science
• Pharmaceutical Sciences

Background:

• Many drugs are administered on mucosal surfaces, but poor mucoadhesion limits bioavailability.
• Developing effective mucoadhesive drug delivery systems is essential for enhancing drug performance.
• Gold nanoparticles (AuNPs) present a potential platform for mucoadhesive drug delivery.

Purpose of the Study:

• To investigate the mucoadhesive properties of gold nanoparticles (AuNPs).
• To develop and validate quantitative methods for assessing mucoadhesion.
• To explore the correlation between AuNP structure and mucin interaction.

Main Methods:

• Synthesis of two types of gold nanoparticles: AuNP1 (internal thiols) and AuNP2 (internal and peripheral thiols).
• Development of quantitative colorimetric, UV-visible spectroscopy, and fluorescence spectroscopy protocols.
• Proposal of a global correction factor for the inner filter effect in spectrofluorimetry.

Main Results:

• Mucins interacted deeply with AuNP1, perturbing their core, while interacting peripherally with AuNP2.
• A higher number of mucins interacted with AuNP2 compared to AuNP1, as indicated by quantitative methods.
• The developed spectroscopic methods provide reliable assessment of mucoadhesive properties.

Conclusions:

• Gold nanoparticles exhibit significant mucoadhesive properties, influenced by thiol group distribution.
• AuNP2, with peripheral thiol groups, demonstrated stronger mucin interaction, suggesting enhanced mucoadhesion.
• This mucoadhesive capability of AuNPs can be leveraged to improve drug delivery on mucosal surfaces.