Integrated microfluidic enzyme reactor mass spectrometry platform for detection of anthrax lethal factor

Area of Science:

• Biochemistry
• Analytical Chemistry
• Biotechnology

Background:

• Bacillus anthracis infection involves a lethal toxin comprising protective antigen and lethal factor (LF).
• Accurate and rapid detection of LF is crucial for early anthrax diagnosis and treatment.
• Current detection methods may lack the speed and sensitivity required for timely clinical response.

Purpose of the Study:

• To develop and validate a coupled microfluidic enzyme reactor mass spectrometry platform for sensitive LF detection.
• To demonstrate the platform's capability for efficient sample preparation and rapid analysis.
• To establish the detection limit and dynamic range for LF quantification.

Main Methods:

• A microfluidic reactor was designed for solid-phase capture and concentration of LF using anti-LF monoclonal antibodies on magnetic beads.
• Immobilized LF was subjected to enzymatic hydrolysis using an optimized peptide substrate.
• Cleavage products were analyzed via mass spectrometry coupled to the microfluidic system.

Main Results:

• The platform demonstrated efficient sample preparation with high sensitivity and reduced reagent consumption.
• Reproducible detection of anthrax lethal factor was achieved in the concentration range of 40 to 0.5 ng/mL.
• A low detection limit of 1 ng/mL was established, with analysis completed in under 15 minutes.

Conclusions:

• The developed microfluidic enzyme reactor mass spectrometry platform provides a rapid and sensitive method for LF detection.
• This technology serves as a promising diagnostic tool for early anthrax prognosis.
• The system's efficiency and speed are advantageous for point-of-care or field-based diagnostics.