Magnetic detection is entirely different from existing (e.g., optical) platforms, overcoming some inherent limitations and providing fundamental advantages. Particularly useful is the ability to perform ultra-sensitive mix and measure assays directly in complex matrices (e.g. blood, serum) since biological substances inherently do not generate a magnetic signal for our magnetic measurements. Our target applications benefit from a combination of these advantages that are not available with existing methods.
The key benefits are:
Major Benefits
· Ultra-high sensitivity, can quantitatively detect <1,000 labels (<attomoles for sandwich immunoassays, 40 cells for surface receptors)
· “Mix and measure” format enables fast results, easy to automate, limited sample handling as no need to separate out unbound labels
· Perform assays in serum and blood since minimal biological interference for magnetic detection
· Ability to apply forces to magnetic labels using magnetic gradient fields to reduce non specific binding and increase signal to noise
Other Benefits
· Inexpensive and non-toxic labels (iron oxide)
· Simple measurement, little training required
· Ability to reduce assay incubation time using magnetic fields to move ("stir") labels
· Capability for binding and real-time kinetics information
· High label stability, can re-measure samples, archive