Isolation and quantification of botulinum neurotoxin from complex matrices using the BoTest matrix assays

Area of Science:

• Biochemistry
• Analytical Chemistry
• Toxicology

Background:

• Accurate detection and quantification of botulinum neurotoxin (BoNT) are crucial for pharmaceutical, environmental, and food safety applications.
• Current mouse bioassays are sensitive but lack the precision, throughput, and ethical appeal for routine testing.
• Existing in vitro assays often fail in complex sample matrices.

Purpose of the Study:

• To present a novel protocol for detecting and quantifying BoNT in complex matrices.
• To offer a high-throughput, animal-free alternative to traditional BoNT testing methods.
• To validate the assay's applicability across various sample types.

Main Methods:

• A three-part assay involving sample preparation, immunoprecipitation using antibody-coated paramagnetic beads, and quantification of proteolytic activity.
• Utilizes a fluorogenic reporter for BoNT activity measurement.
• Adapted for high-throughput 96-well plate format with both liquid and solid matrices.

Main Results:

• Demonstrated successful detection and quantification of BoNT/A in diverse matrices including PBS, drug product, culture supernatant, milk, and tomatoes.
• Assay requires approximately 2 hours of manual preparation.
• Total assay times range from 4 to 26 hours, depending on sample complexity and sensitivity requirements.

Conclusions:

• The BoTest Matrix assay provides a robust and efficient method for BoNT detection in complex samples.
• This assay serves as a promising replacement for animal-based bioassays in various testing scenarios.
• The protocol is suitable for routine use in food safety, pharmaceutical manufacturing, and outbreak investigations.