Nucleic acid-based materials enable sub-nanometer precision in self-assembly for fields including biophysics, diagnostics, therapeutics, photonics, and nanofabrication. However, structural DNA nanotechnology has been limited to substantially hydrated media. Transfer to organic solvents commonly used in polymer and peptide synthesis results in the alteration of DNA helical structure or reduced thermal stabilities. Here we demonstrate that gamma-modified peptide nucleic acids (
Peptide nucleic acids (PNAs) are nucleic acid analogs with hybridization properties and enzymatic stability superior to that of DNA. In addition to gene targeting applications, PNAs have garnered significant attention as bio‐polymers due to the Watson–Crick‐based molecular recognition and flexibility of synthesis. Here, PNA amphiphiles are engineered using chemically modified gamma PNA (8 mer in length) containing hydrophilic diethylene glycol units at the gamma position and covalently conjugated lauric acid (C12) as a hydrophobic moiety. Gamma PNA (γ PNA) amphiphiles self‐assemble into spherical vesicles. Further, nano‐assemblies (NA) are formulated using the amphiphilic γ PNA as a polymer via ethanol injection‐based protocols. Comprehensive head‐on comparison of the physicochemical and cellular uptake properties of PNA derived self‐ and NA is performed. Small‐angle neutron and X‐ray scattering analysis reveal ellipsoidal morphology of γ PNA NA that results in superior cellular delivery compate to the spherical self‐assembly. Next, the functional activities of γ PNA self‐and NA in lymphoma cells via multiple endpoints, including gene expression, cell viability, and apoptosis‐based assays are compared. Overall, it is established that γ PNA amphiphile is a functionally active bio‐polymer to formulate NA for a wide range of biomedical applications.
more » « less- NSF-PAR ID:
- 10446457
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 32
- Issue:
- 7
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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