These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Stimuli responsive polymorphism of C12NO/DOPE/DNA complexes: Effect of pH, temperature and composition.
    Author: Hubčík L, Funari SS, Pullmannová P, Devínsky F, Uhríková D.
    Journal: Biochim Biophys Acta; 2015 May; 1848(5):1127-38. PubMed ID: 25660321.
    Abstract:
    N,N-dimethyldodecylamine-N-oxide (C12NO) is a surfactant that may exist either in a neutral or cationic protonated form depending on the pH of aqueous solutions. Using small angle X-ray diffraction (SAXD) we observe the rich structural polymorphism of pH responsive complexes prepared due to DNA interaction with C12NO/dioleoylphosphatidylethanolamine (DOPE) vesicles and discuss it in view of utilizing the surfactant for the gene delivery vector of a pH sensitive system. In neutral solutions, the DNA uptake is low, and a lamellar Lα phase formed by C12NO/DOPE is prevailing in the complexes at 0.2≤C12NO/DOPE<0.6 mol/mol. A maximum of ~30% of the total DNA volume in the sample is bound in a condensed lamellar phase LαC at C12NO/DOPE=1 mol/mol and pH7.2. In acidic conditions, a condensed inverted hexagonal phase HIIC was observed at C12NO/DOPE=0.2 mol/mol. Commensurate lattice parameters, aHC≈dLC, were detected at 0.3≤C12NO/DOPE≤0.4 mol/mol and pH=4.9-6.4 suggesting that LαC and HIIC phases were epitaxially related. While at the same composition but pH~7, the mixture forms a cubic phase (Pn3m) when the complexes were heated to 80°C and cooled down to 20°C. Finally, a large portion of the surfactant (C12NO/DOPE>0.5) stabilizes the LαC phase in C12NO/DOPE/DNA complexes and the distance between DNA strands (dDNA) is modulated by the pH value. Both the composition and pH affect the DNA binding in the complexes reaching up to ~95% of the DNA total amount at acidic conditions.
    [Abstract] [Full Text] [Related] [New Search]