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Updated: Jun 21, 2026
11:53
Predicting Gene Silencing Through the Spatiotemporal Control of siRNA Release from Photo-responsive Polymeric Nanocarriers
Published on: July 21, 2017
Nucleic acid therapeutic carriers with on-demand triggered release
Siddarth Venkatesh1, Jacek Wower, Mark E Byrne
1Biomimetic and Biohybrid Materials, Biomedical Devices, and Drug Delivery Laboratories, Department of Chemical Engineering, Auburn University, Auburn, Alabama 36849, USA.
Bioconjugate Chemistry
|August 13, 2009
Summary
This study introduces novel biohybrid polymer networks for controlled oligonucleotide release using specific enzymes. The platform enables programmable drug and gene delivery with tunable release profiles.
Area of Science:
- Biomaterials Science
- Polymer Chemistry
- Molecular Biology
Background:
- Biohybrid polymer networks offer potential for advanced drug and gene delivery.
- Controlled release of nucleic acid sequences is crucial for therapeutic applications.
Purpose of the Study:
- To synthesize and characterize novel polymer networks for enzyme-triggered oligonucleotide release.
- To investigate the potential of these networks as programmable gene delivery vehicles.
Main Methods:
- Copolymerization of chemical monomers and acrylated oligonucleotides into polymer networks.
- Enzymatic cleavage using restriction enzyme BamHI and DNase I.
- Phosphoimaging for oligonucleotide incorporation quantification.
- Analysis of release kinetics, diffusion coefficients, and temperature responsiveness.
- In vitro degradation of HIV-1 mRNA using released deoxyribozyme.
Main Results:
- Successfully incorporated 70% of oligonucleotides into polymer networks.
- Demonstrated enzyme-specific cleavage and near zero-order release of oligonucleotides.
- Characterized diffusion coefficients and diffusional exponents, showing tunability with cross-linking.
- Observed sigmoidal temperature-responsive release matching oligonucleotide melting temperatures.
- Showcased release of a functional RNA-cleaving deoxyribozyme that degraded HIV-1 mRNA.
Conclusions:
- Developed a novel, modular biohybrid platform for controlled oligonucleotide delivery.
- Harnessed enzyme specificity for programmable nucleic acid release.
- Demonstrated potential for creating sophisticated, on-demand gene delivery systems.
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