Optimized sample buffer for dispersed, high-resolution capillary zone electrophoretic separation of Escherichia coli...

Area of Science:

• Microbiology
• Analytical Chemistry
• Biophysics

Background:

• Capillary zone electrophoresis (CZE) offers high-resolution chemical separations.
• Applying CZE to microbial samples could advance understanding of bacterial physiology.
• Bacterial cell hetero-aggregation under electric fields limits CZE study of microbial samples.

Purpose of the Study:

• To optimize capillary zone electrophoresis (CZE) for microbial sample separation.
• To identify effective sample buffer additives for reducing bacterial aggregation and improving separation.
• To enhance the loading capacity and peak resolution for bacterial CZE.

Main Methods:

• Tested various sample buffers and additives with a 20 mM Tris-HCl background electrolyte for CZE.
• Modified sample buffers, keeping background electrolyte constant, to compare additive effects.
• Utilized automated CZE for separation and fractionation of Escherichia coli B.

Main Results:

• A modified sample buffer with neutral salts and glycerol increased loading capacity 20-fold.
• Glycerol-containing buffer reduced peak width/broadening by 86% compared to previous methods.
• The glycerol-modified buffer mitigated aggregation and capillary adhesion for complex environmental microbiota.

Conclusions:

• Optimized sample buffers, particularly with glycerol, significantly improve CZE performance for bacterial samples.
• This method enhances separation efficiency and reduces aggregation issues in microbial CZE.
• The findings facilitate deeper insights into bacterial physiology and behavior using CZE.