Nanoparticle-stabilized liposomes for pH-responsive gastric drug delivery
Soracha Thamphiwatana1, Victoria Fu, Jingying Zhu
1Department of NanoEngineering, ‡Moores Cancer Center, University of California, San Diego , La Jolla, California 92093, United States.
Langmuir : the ACS Journal of Surfaces and Colloids
|August 31, 2013
Summary
This study introduces pH-responsive liposomes for targeted drug delivery. These gold nanoparticle-stabilized liposomes remain stable in the stomach but release antimicrobials effectively in neutral pH environments for enhanced bacterial treatment.
Area of Science:
- Biotechnology
- Materials Science
- Pharmaceutical Sciences
Background:
- Gastric antimicrobial delivery faces challenges due to the harsh acidic environment of the stomach.
- Developing targeted delivery systems that respond to specific pH changes is crucial for effective treatment.
- Helicobacter pylori infections require novel therapeutic strategies for eradication.
Purpose of the Study:
- To develop a novel pH-responsive liposome system for enhanced gastric antimicrobial delivery.
- To investigate the stability and drug release characteristics of gold nanoparticle-stabilized liposomes at different pH levels.
- To evaluate the efficacy of this system against Helicobacter pylori in a simulated gastric environment.
Main Methods:
- Chitosan-modified gold nanoparticles were adsorbed onto negatively charged phospholipid liposomes.
- The pH-responsive behavior, stability, and fusion activity of the nanoparticle-stabilized liposomes were assessed.
- Doxycycline-loaded liposomes were tested for their antimicrobial efficacy against Helicobacter pylori at neutral pH.
Main Results:
- Liposomes exhibited excellent stability and minimal cargo release at gastric pH (~2).
- At neutral pH (~7), gold nanoparticle stabilizers detached, enabling liposome fusion with bacterial membranes.
- Doxycycline-loaded liposomes demonstrated superior bactericidal efficacy against Helicobacter pylori compared to free doxycycline.
Conclusions:
- The gold nanoparticle-stabilized liposome system is a promising platform for pH-responsive gastric drug delivery.
- The system remains stable in the stomach but becomes active upon reaching neutral pH environments, such as the mucus layer.
- This targeted delivery approach offers enhanced antimicrobial activity and therapeutic potential for gastric infections.
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