PExM: polyplex expansion microscopy for cell trafficking studies

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Cell Biology

Background:

• Nanomedicine holds great promise for healthcare but faces challenges in visualizing nano-bio interactions.
• Current nanoscopy techniques like expansion microscopy (ExM) are valuable but require adaptation for specific nanocarriers.
• Understanding nanocarrier behavior within cells is crucial for advancing nanomedicine.

Purpose of the Study:

• To adapt expansion microscopy (ExM) for visualizing polymer-based nanocarriers, specifically polyplexes, within cells.
• To introduce polyplex expansion microscopy (PExM) as a novel method for studying nanocarrier trafficking.
• To establish PExM as a high-resolution, accessible tool for nanomedicine research.

Main Methods:

• Utilized expansion microscopy (ExM) principles and adapted them for polymer-based nanocarriers.
• Developed a protocol for expanding cells containing polyplex nanocarriers.
• Analyzed the intracellular trafficking of polyplexes using the established PExM technique.

Main Results:

• Successfully adapted ExM to create PExM for visualizing polyplex nanocarriers within cellular environments.
• Demonstrated PExM's capability to analyze the trafficking pathways of polyplex nanoparticles.
• Validated PExM as a high-resolution imaging technique applicable to primary amine-containing polymeric nanoparticles.

Conclusions:

• PExM offers a powerful new method for studying nanomedicine behavior at the cellular level.
• This technique overcomes limitations of existing methods by enabling precise visualization of polyplex trafficking.
• PExM provides a cost-effective alternative to super-resolution microscopy for nanocarrier research.