Sandia Labs announces new electrochemical sensor

Published 4 May 2007

Unlike current methods, this one tests multiple biomolecules simultaneously; “diazonium-based surface chemistry”

More news from the eggheads at Sandia National Laboratories, once again in the biosensor department. A team of researchers there has developed a new type of electrochemical sensor that simultaneoulsy tests for a range of bioagent signatures — the opposite of the approach used by many existing biosensors, which often only look for one type of biomolecule at a time. For example, instead of using only an antibody that binds to the surface of an anthrax spore, the new Sandia sensor could test for several DNA sequences and internal and external proteins unique to anthrax. “Identification of several DNA sequences and protein markers will allow for detection of multiple targets and accurate discrimination between similar bioagent threats,” said researcher Jason Harper.

The actual chemistry involved is beyond our competence, so we leave it to researcher David Wheeler to explain: “This diazonium-based surface chemistry can be selectively deposited onto several types of substrates by controlling the charge of the substrate in the diazonium solution,” Wheeler said. “Because the deposition of the diazonium molecules is based on the application of an electrical potential, the selective patterning of individually addressable electrodes is possible. Upon deposition, covalent bonds are formed with the substrate, producing a highly stable film.”