“This is an immunoassay done in an elegant way,” Paul Chapman, president and CEO of Quanterix, told Bio-Pharma-Reporter. “On average it’s 1000-fold more sensitive than any standard Elisa today. The way we can achieve that is by isolating single molecules in a tiny well in the same way as an Elisa.”
The company’s proprietary Simoa technology is based on the isolation of individual immunocomplexes on paramagnetic beads using standard Elisa reagents. But unlike the standard immunoassays, Simoa technology can trap single molecules in femtoliter-sized wells and determine if the individual beads are bound to the target analyte or not.
Conventional assay reaction volumes are relatively large -- 100 or 50 µL -- and take millions of molecules to create tens of millions of fluorophores generated by the enzyme substrate complex diffusing in this dilute solution before an optical signal can be obtained.
The Simoa assay, however, is about two billion times smaller, so a single target molecule in a sealed microwell can generate enough fluorophores to be measured using conventional fluorescence imaging. In addition, the instrument has a processing speed of 68 samples/hour, yielding up to 680 results/hour for a 10-plex, according to Quanterix.
“The ultrasensitive diagnostic platform can measure individual proteins at concentrations 1,000 times lower than the best immunoassays available,” Chapman said.
A recent study at Tufts University used the Simoa technology to prove that the detection of cancer-relevant biomarkers could be found in a simple blood test.
Sony DADC
Simoa also can now use a disc designed and manufactured by Sony DADC BioSciences, called the Simoa Disc. The disc can achieve higher levels of sensitivity and precision and is the first diagnostic consumable whose assay technology is based on optical disc formats by Sony DADC.
The Quanterix Simoa disc leverages established high-volume polymer replication based on optical disc technology for low cost manufacturing of disposable single molecule arrays.
Chapman added, “The Simoa Disc offers a multitude of advantages for low-cost manufacturing, ease of automation, and instrument development to enable applications in biomarker research and clinical diagnostics.”