Cyclam-based polymeric copper chelators for gene delivery and potential PET imaging

Area of Science:

• Polymer Chemistry
• Biomaterials Science
• Nanotechnology

Background:

• Developing effective and safe non-viral gene delivery vectors is crucial for gene therapy.
• Polycationic materials are widely investigated for nucleic acid complexation and delivery.
• Copper chelators offer potential for targeted delivery and therapeutic applications.

Purpose of the Study:

• To synthesize and characterize novel reducible polycationic copper chelators (RPCs) based on 1,4,8,11-tetraazacyclotetradecane (cyclam).
• To evaluate the cytotoxicity and gene transfection efficiency of these RPCs and their Cu(II) complexes.
• To explore their potential as nucleic acid delivery vectors for theranostic applications.

Main Methods:

• Synthesis of RPCs via Michael addition, controlling molecular weight (4400-13,800 Da) through reaction parameters.
• Characterization of polycations and their ability to complex Cu(II).
• In vitro assessment of cytotoxicity compared to poly(ethyleneimine) (PEI) and evaluation of transfection activity.

Main Results:

• RPCs with controlled molecular weights were successfully synthesized, retaining copper-chelating ability.
• Polycations containing disulfide bonds exhibited significantly lower cytotoxicity than control PEI.
• RPCs and their Cu(II) complexes demonstrated high in vitro transfection efficiency.

Conclusions:

• Reducible polycationic copper chelators are effective and less cytotoxic gene delivery vectors.
• The developed polycationic Cu(II) chelates show promise for nucleic acid delivery.
• These materials represent a potential platform for future theranostic applications in gene therapy.