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Fabricating Superhydrophobic Polymeric Materials for Biomedical Applications
Published on: August 28, 2015
Synthesis and characterization of a cationic poly(beta-hydroxyalkanoate).
1Department of Chemistry, University of Alabama in Huntsville, 301 Sparkman Drive, Huntsville, Alabama 35899, USA.
Biomacromolecules
|July 24, 2008
Summary
Researchers synthesized the first cationic biodegradable polymer, polyhydroxyalkanoate (PHA), by modifying bacterial polyesters. This new cationic PHA is water-soluble and shows potential for nucleic acid delivery systems.
Area of Science:
- Polymer Chemistry
- Biotechnology
- Materials Science
Background:
- Poly(beta-hydroxyalkanoates) (PHAs) are biodegradable polyesters synthesized by bacteria, offering tunable structures via feedstock control.
- Current methods for functionalizing PHAs are limited by the organism's metabolic capabilities.
- Chemical modification of PHA side chains is crucial for developing novel materials with advanced properties.
Purpose of the Study:
- To synthesize the first cationic PHA through chemical modification of a naturally occurring PHA.
- To functionalize poly(beta-hydroxy-octanoate)-co-(beta-hydroxy-10-undecenoate) (PHOU) to introduce cationic properties.
- To explore the potential of the novel cationic PHA as a nucleic acid delivery system.
Main Methods:
- Production of PHOU by Pseudomonas putida Gpo1.
- Conversion of vinyl-terminated side chains of PHOU to terminal epoxides.
- Modification of epoxidized PHOU with diethanolamine.
- Characterization using NMR (1H, COSY, HSQC) and Gel Permeation Chromatography (GPC).
Main Results:
- Successful synthesis of a novel cationic PHA: poly(beta-hydroxy-octanoate)-co-(beta-hydroxy-11-(bis(2-hydroxyethyl)-amino)-10-hydroxyundecanoate) (PHON).
- Characterization confirmed the introduction of tertiary amine groups, protonated at physiological pH, leading to cationic properties.
- The resulting cationic PHA exhibited solubility in polar solvents, including water.
- A decrease in molecular weight was observed due to aminolysis during the modification process.
Conclusions:
- A novel biodegradable cationic PHA (PHON) was synthesized via chemical modification of PHOU.
- The new polymer possesses cationic characteristics and is soluble in polar solvents.
- The developed cationic PHA holds promise for applications in nucleic acid delivery systems.
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