Butyrylcholinesterase-Loaded Liposomes and Polymersomes: Catalytic Parameters for Three Types of Substrates

Area of Science:

• Biotechnology
• Nanotechnology
• Supramolecular Chemistry

Background:

• Organophosphate (OP) poisoning necessitates effective treatments.
• Enzyme encapsulation in nano-compartments offers a promising prophylactic and therapeutic strategy.
• Butyrylcholinesterase (BChE) is a key enzyme for detoxifying OPs and other esters.

Purpose of the Study:

• To develop and characterize nano-scavengers for OP detoxification.
• To compare the efficacy of liposome- and polymersome-based nano-compartments.
• To evaluate the catalytic activity of encapsulated BChE.

Main Methods:

• Synthesis of PEGylated liposomes and polyethyleneglycol-polypropylenesulfide (PEG-PPS) polymersomes encapsulating human BChE.
• Characterization of nano-scavengers, including size (approx. 100 nm), encapsulation efficiency, and enzyme release rate.
• Analysis of the catalytic properties (kcat) of encapsulated BChE using various ester substrates (butyrylthiocholine iodide, phenyl acetate, aspirin).

Main Results:

• BChE-polymersomes demonstrated higher encapsulation efficiency (95%) and slower enzyme release (>7 days) than BChE-liposomes.
• Polymersomes exhibited significantly higher catalytic activity (kcat) compared to non-encapsulated BChE, particularly with neutral phenyl acetate.
• Catalytic efficiency was influenced by nano-compartment formulation, lipophilicity, polymer structure, and substrate polarity.

Conclusions:

• PEG-PPS polymersomes represent a superior platform for BChE encapsulation compared to liposomes.
• These nano-scavengers hold potential for the prophylaxis and treatment of OP poisoning.
• Further research into nano-system-functionalized nano-compartments can advance enzyme-based detoxification strategies.