Release of DNA from polyelectrolyte multilayers fabricated using 'charge-shifting' cationic polymers: tunable...

Area of Science:

• Materials Science
• Polymer Chemistry
• Biomedical Engineering

Background:

• Controlling the release of DNA from surfaces is crucial for various biomedical applications.
• Existing methods for fabricating DNA-releasing films often lack tunable release rates.
• Layer-by-layer assembly is a common technique for creating thin films with specific properties.

Purpose of the Study:

• To develop a novel approach for designing multilayered polyelectrolyte thin films (PEMs) with tunable DNA release capabilities.
• To utilize 'charge-shifting' polymers to control the erosion rates of PEMs and subsequent DNA release.
• To achieve a broad range of DNA release profiles, including sequential release of multiple DNA constructs.

Main Methods:

• Synthesis of two 'charge-shifting' cationic polymers (polymers 1 and 2) via ring-opening reactions.
• Fabrication of PEMs using layer-by-layer assembly with DNA and the synthesized polymers.
• Characterization of polymer hydrolysis rates and DNA release profiles from the fabricated PEMs.

Main Results:

• Polymers 1 and 2 exhibited significantly different ester hydrolysis rates (half-lives of ~200 days and ~6 days, respectively).
• PEMs fabricated with polymer 2 released DNA rapidly (~3 days), while those with polymer 1 released DNA slowly (~1 month).
• Intermediate and sequential DNA release profiles were achieved by using polymer mixtures or hierarchical film structures.

Conclusions:

• The developed 'charge-shifting' polymers offer a versatile platform for precisely controlling DNA release kinetics from thin films.
• This approach allows for the design of functional films with tailored release rates without synthesizing new polymer structures.
• The technology holds promise for advanced biomedical applications requiring sophisticated control over the timing and order of agent release.