09 Sep 2011 The petri dish gets a makeover
A nanopore membrane creates faster, surer cultures for everything from hospital diagnostics to food safety and water-quality checks.
A new type of diagnostic could let laboratories identify the presence of dangerous bacteria up to five times faster than conventional methods. The test could reduce unnecessary antibiotic use and provide more reliable water-quality test results.
The key to the process is a membrane with nanosized pores, which enable rapid growth and identification of live organisms.
Current methods of identifying bacterial infections in hospitals seem almost antiquated: Swab, rub on petri dish filled with agar, and wait.
Some bacteria can take 48 hours or more to grow into visible colonies. But the new technology, developed by Hubbard, Ohio-based Nanologix, speeds up the process. Bacteria, and potentially viruses, move through the pores of its membrane, and grow there. Then the membrane is plucked off the agar and placed on a staining plate.
“People knew for decades that microcolonies would be present in culture, but there was no way to transfer them or stain them in a way to make them visible,” says Nanologix CEO Bret Barnhizer.
But the company’s technology—”bionanopore” membranes and “bionanofilters”—is sensitive enough to detect a single cell. And when the nanofilter is saturated with antibodies specific to a particular bacteria or virus, it can quickly indicate whether a particular offender is present……