Assembling structurally customizable synthetic carriers of siRNA through thermodynamically self-regulated process

Area of Science:

• Biomaterials Science
• Nanotechnology
• Polymer Chemistry

Background:

• Synthetic siRNA carriers are crucial for gene therapy.
• Previous polywraplex carriers utilized branched polyethyleneimine (PEI).
• Characterization of complex polymer structures can be challenging.

Purpose of the Study:

• To investigate the use of dendrimers as crosslinking junctions in polywraplex siRNA carriers.
• To assess if dendrimer incorporation affects the physicochemical and biological properties of polywraplexes.
• To explore electron microscopy as a tool for characterizing dendrimer-crosslinked polywraplexes.

Main Methods:

• Synthesis of a novel networked cationic polymer using polyamidoamine (PAMAM) dendrimers as crosslinking junctions.
• Physicochemical characterizations including size and zeta potential measurements.
• Biological assays evaluating siRNA leakage, degradation, and gene silencing efficacy.

Main Results:

• Dendrimer-crosslinked polywraplexes maintained similar network structures and physicochemical properties compared to PEI-based ones.
• Electron microscopy enabled visualization of the dendrimer crosslinking junctions.
• The dendrimer-based polywraplexes exhibited comparable biological functions, including effective gene silencing.
• No significant alteration in chemical properties or biological functions was observed.

Conclusions:

• Dendrimers can be effectively used as crosslinking junctions in the rational design of networked siRNA carriers.
• The incorporation of dendrimers facilitates structural characterization via electron microscopy.
• Dendrimer-based polywraplexes offer a promising platform for gene delivery with retained functionality.