The Effects of the Carrier and Ligand Spatial Conformation on RNA Nanodrug Cell Delivery

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Molecular Biology

Background:

• Small interfering RNA (siRNA) holds significant therapeutic promise for cancer treatment.
• Effective delivery of siRNA nanodrugs is crucial but faces challenges related to ligands and carriers.
• Targeting α_Vβ₃ integrins is a key strategy in siRNA delivery systems.

Purpose of the Study:

• To analyze the binding specificity and dynamics of linear and circular RGD ligands to α_Vβ₃ integrins.
• To evaluate the impact of ligands and carriers on the cell entry dynamics of RNA nanodrugs.
• To assess the delivery efficiency of RNA nanodrugs at the single-cell level.

Main Methods:

• Super-resolution direct stochastic optical reconstruction microscopy (dSTORM) for morphology mapping.
• Single-molecule force spectroscopy (SMFS) to investigate binding dynamics.
• Force tracing technique for evaluating cell entry parameters at the single-particle level.
• Atomic force microscopy (AFM)-based nanoindentation for assessing delivery efficiency.

Main Results:

• Detailed analysis of RGD ligand binding specificity and dynamics to α_Vβ₃ integrins.
• Quantification of ligand and carrier effects on RNA nanodrug cell entry parameters.
• Demonstration of AFM-based nanoindentation for evaluating nanodrug delivery efficiency.

Conclusions:

• Understanding ligand-integrin interactions is vital for designing effective siRNA nanodrug delivery systems.
• The study provides a foundation for rational design strategies to improve nanodrug delivery efficiency.
• These findings contribute to advancing siRNA-based cancer therapeutics.