A sponge-like nanoporous gold could be key to new devices to identify disease-causing agents in humans and plants, says a group from the UC Davis Department of Electrical and Computer Engineering.
The team demonstrated that they could detect nucleic acids using nanoporous gold in mixtures of other biomolecules that would gum up most detectors. This way enables sensitive detection of DNA in complex biological samples, such as serum from whole blood.
"Nanoporous gold can be imagined as a porous metal sponge with pore sizes that are a thousand times smaller than the diameter of a human hair. What happens is the debris in biological samples, such as proteins, is too large to go through those pores, but the fiber-like nucleic acids that we want to detect can actually fit through them. It's almost like a natural sieve," said Erkin Seker, assistant professor of electrical and computer engineering at UC Davis.
Seker explains that rapid and sensitive detection of nucleic acids plays a vital role in early detection of pathogenic microbes and disease biomarkers.
Current sensor approaches usually require nucleic acid purification that relies on multiple steps and specialized laboratory equipment, which limit the sensors' use in the field. The researchers' method reduces the need for purification.
"So now we hope to have largely eliminated the need for extensive sample clean-up, which makes the process conducive to use in the field," Seker said.
The researchers hope the technology can be translated into the development of miniature point-of-care diagnostic platforms for agricultural and clinical applications.