Efficient Polymeric Nanoparticle Gene Delivery Enabled Via Tri- and Tetrafunctional Branching.

Area of Science:

• Biomaterials Science
• Nanotechnology
• Gene Delivery

Background:

• Poly(β-amino ester) (PBAE) nanoparticles are promising nonviral gene vectors.
• Branched PBAEs (BPBAEs) may offer advantages over linear PBAEs, but their structural effects require further investigation.

Purpose of the Study:

• To synthesize and evaluate a library of BPBAEs with varying branching functionalities.
• To investigate the impact of polymer architecture on nanoparticle formation, DNA complexation, and gene delivery efficiency.
• To compare the performance of optimized BPBAE nanoparticles against linear PBAE counterparts.

Main Methods:

• Synthesis of a library of tri- and tetrafunctional BPBAEs.
• Self-assembly of BPBAEs with DNA to form nanoparticles.
• Characterization of nanoparticle size, charge, and DNA encapsulation efficiency.
• In vitro transfection studies in diverse cell types.
• Cellular viability assays.

Main Results:

• BPBAE nanoparticles were successfully synthesized, forming monodisperse, small (∼50 nm) particles with high cationic charge.
• Moderate branching in BPBAE structures optimized DNA encapsulation, cellular uptake, and gene expression at low polymer and DNA concentrations.
• Optimized BPBAE nanoparticles demonstrated superior in vitro DNA delivery efficiency across various cell types compared to linear PBAE controls, while maintaining high cell viability.
• BPBAE nanoparticles also showed efficacy in delivering mRNA and siRNA.

Conclusions:

• BPBAE structure significantly influences nanoparticle properties and gene delivery performance.
• Optimized BPBAE nanoparticles represent a versatile and efficient platform for nonviral delivery of DNA, mRNA, and siRNA.
• These findings highlight the potential of architecturally controlled BPBAEs for advanced nucleic acid therapeutics.