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Self-Assembly of Hybrid Lipid Membranes Doped with Hydrophobic Organic Molecules at the Water/Air Interface
Published on: May 1, 2020
Hybrid materials from intermolecular associations between cationic lipid and polymers
Edla M A Pereira1, Priscila M Kosaka, Heloísa Rosa
1Instituto de Química, Universidade de São Paulo, CP, Sãu Paulo SP, Brazil.
The Journal of Physical Chemistry. B
|July 18, 2008
Summary
Hybrid polymer-lipid films were created using poly(methyl methacrylate) (PMMA) and polystyrene (PS) with dioctadecyldimethylammonium bromide (DODAB). PMMA-DODAB films showed stability and antimicrobial properties, unlike PS-DODAB films.
Area of Science:
- Materials Science
- Polymer Chemistry
- Biomaterials
Background:
- Cationic lipids like dioctadecyldimethylammonium bromide (DODAB) possess antimicrobial properties.
- Developing stable hybrid films with tunable properties is crucial for advanced material applications.
Purpose of the Study:
- To investigate the intermolecular interactions between DODAB and two model polymers: poly(methyl methacrylate) (PMMA) and polystyrene (PS).
- To characterize the resulting hybrid thin films and assess their stability and antimicrobial efficacy.
- To determine the influence of polymer-lipid miscibility on film properties.
Main Methods:
- Preparation of hybrid thin films via spin-coating on silicon wafers.
- Characterization using ellipsometry, wettability, optical microscopy, atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC).
- Antimicrobial activity testing against Escherichia coli.
Main Results:
- PMMA-DODAB films exhibited smooth surfaces and stability due to favorable ion-dipole interactions.
- PS-DODAB films showed poor stability, lipid segregation, and high rugosity due to a lack of such interactions.
- The hybrid PMMA/DODAB coating effectively inhibited the growth of E. coli, transferring DODAB's antimicrobial properties.
Conclusions:
- Intermolecular interactions significantly dictate the stability and morphology of polymer-lipid hybrid films.
- PMMA is a suitable polymer for creating stable, antimicrobial hybrid films with DODAB.
- The PMMA/DODAB hybrid coating demonstrates potential as an effective antimicrobial surface.
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