Hydrogen peroxide production from reactive liposomes encapsulating enzymes

Area of Science:

• Biochemistry and Biophysics
• Materials Science
• Nanotechnology

Background:

• Liposomes are versatile drug delivery systems with tunable properties.
• Encapsulating enzymes within liposomes enables localized biochemical reactions.
• Understanding enzyme-liposome interactions is crucial for optimizing biosensor performance.

Purpose of the Study:

• To prepare and characterize reactive cationic and anionic liposomes.
• To investigate the encapsulation of glucose oxidase (GO) with other enzymes.
• To analyze hydrogen peroxide generation and its dependence on various factors.

Main Methods:

• Preparation of cationic and anionic liposomes using dimyristoylphosphatidylcholine (DMPC), cholesterol, and specific lipids.
• Enzyme encapsulation using the vesicle extrusion technique (GO with HRP or LPO).
• Monitoring hydrogen peroxide production via a Rank electrode system and measuring substrate permeability.

Main Results:

• Hydrogen peroxide production increased linearly with glucose oxidase incorporation.
• Enzyme activity was modulated by enzyme combinations, substrate concentration, and temperature.
• Liposome encapsulation affected methyl glucoside permeability, with increased permeability in anionic liposomes and decreased in cationic ones.

Conclusions:

• Reactive liposomes can be engineered for enzyme-based biosensing applications.
• Enzyme-bilayer interactions significantly influence liposome properties and performance.
• Optimizing liposome composition and reaction conditions enhances biosensor sensitivity and efficiency.