Lab-on-a-chip for botulinum neurotoxin a (BoNT-A) activity analysis

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Toxicology

Background:

• Botulinum neurotoxin serotype A (BoNT-A) detection is crucial for diagnostics.
• Existing methods for BoNT-A detection can be complex and require laboratory settings.
• There is a need for rapid, sensitive, and portable detection systems.

Purpose of the Study:

• To design, fabricate, and test a Lab-on-a-chip (LOC) device for in vitro detection of BoNT-A activity.
• To develop a portable fluorescence detection system for BoNT-A.
• To assess the sensitivity and potential of the LOC system for point-of-care diagnostics.

Main Methods:

• Fabrication of a six-layer LOC device using Laminated Object Manufacturing (LOM) with Poly(methyl methacrylate) (PMMA) and Polycarbonate (PC) layers.
• Development of a Förster Resonance Energy Transfer (FRET) assay utilizing a fluorophore-tagged SNAP-25 peptide substrate specific for BoNT-A light chain (LcA).
• Measurement of FRET fluorescence using a portable charge-coupled device (CCD) fluorescent detector with multi-wavelength light-emitting diode (LED) illumination.

Main Results:

• The LOC system successfully detected LcA activity.
• The system achieved a limit of detection as low as 0.5 nM for LcA, consistent with the in vitro assay sensitivity.
• The portable CCD detector enabled sensitive FRET fluorescence measurement.

Conclusions:

• The developed LOC device combined with a portable CCD detector provides a sensitive and simple system for BoNT-A activity detection.
• This point-of-care system has the potential for use in complex medical assays outside of traditional laboratory environments.
• The technology may improve healthcare delivery, particularly for underserved populations.