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.
Three sets of polyoxometalate (POM)‐based amphiphilic hybrid macromolecules with different rigidity in their organic tails are used as models to understand the effect of molecular rigidity on their possible self‐recognition feature during self‐assembly processes. Self‐recognition is achieved in the mixed solution of two structurally similar, sphere‐rigid T‐shape‐linked oligofluorene(TOF4) rod amphiphiles, with the hydrophilic clusters being Anderson (Anderson‐TOF4) and Dawson (Dawson‐TOF4), respectively. Anderson‐TOF4is observed to self‐assemble into onion‐like multilayer structures and Dawson‐TOF4forms multilayer vesicles. The self‐assembly is controlled by the interdigitation of hydrophobic rods and the counterion‐mediated attraction among charged hydrophilic inorganic clusters. When the hydrophobic blocks are less rigid, e.g., partially rigid polystyrene and fully flexible alkyl chains, self‐recognition is not observed, attributing to the flexible conformation of hydrophobic molecules in the solvophobic domain. This study reveals that the self‐recognition among amphiphiles can be achieved by the geometrical limitation of the supramolecular structure due to the rigidity of solvophobic domains.
more » « less- NSF-PAR ID:
- 10390316
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Macromolecular Rapid Communications
- Volume:
- 44
- Issue:
- 1
- ISSN:
- 1022-1336
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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