Giant Magnetic Resonance (GMR) Assay Principles
Our platform utilizes a sandwich assay in which the target antigen is sandwiched between two antigens, one bound to the magnetic sensor and the other to a superparamagnetic nano particle. Under an external magnetic field, the nanoparticles magnetize and their presence or absence can be detected by the sensor. Using chips with 64 GMR sensors we show rapid multiplex protein detection with a liner dynamic range of over 5-6 orders of magnitude for a diverse range of biological fluids in real time.
*Based on standard LBA process with magnetic nanoparticles used as labels
Instrument and chip
GMR Multiplex Chip
- 80 individual sensors on each chip
- 8 chips with 640 sensors total
- Each sensor can be individually spotted
- 80 biomarkers with controls for the multiplex chip
GMR Reader Unit
- Rugged and reliable
- No optics meaning no calibration of lasers, mirrors etc
- No fluidics means no pumps, valves, etc
- Fully automated
- Hands free incubation
- Bar code system to minimize errors
- No wash necessary
- Flexible assay protocols
- Run time of 1 hour for most sensitive assay
- Run time of 5-10 minutes for express assays
MagArray has 5-6 orders of magnitude greater dynamic range and a 1000 times more sensitive than ELISA.
Compared to ELISA, the MagArray platform is capable of detecting CEA at significantly lower concentrations and at 5-6 orders of magnitude greater dynamic range utilizing the same Ab pair
Matrix insensitive detection in different buffers.
A panel of eight human tumor markers with BSA negative control and epoxy control indicates matrix insensitive detection when shifting from PBS to mouse serum to lysis buffer
Ligand Binding Assay
Our GMR platform is more sensitive than SPR and insensitive to buffer conditions
MagArray platform at least 1000 times more sensitive than Biacore/SPR
MagArray platform insensitive to pH and salinity*
The effect of matrix on protein binding between SPR and MagArray
Buffer: 0.01M HEPES, pH 7.4, 0.15M NaCl, 3mM EDTA
Regeneration: 10mM Gly-HCL, pH 2.5
Analyte: TSH, Ligand: Anti-TSH ab
Biacore X 100
- The same binding pair and buffer conditions were used to compare between MagArray and Biacore
- Plasma was used as a matrix and diluted by PBS to 80%, 50%, 10%, 1%, 0.1%
- MagArray platform kinetic measurements were not affected by matrix
- Biacore did not provide reliable results above 0.1% matrix
- Truly a transformational platform that helps to bridge the gap between in-vitro and in-vivo.
- Matrix insensitive technology for measuring biomolecules in blood, plasma, serum, saliva and urine.
- 1000 times more sensitive than leading SPR technologies in measuring protein-protein interactions.
- Partnership with Hitachi Hi-Technologies allows expansion of platform for unmet needs in biological assays.
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