Diagnostics & Imaging Week Washington Editor

WASHINGTON – Despite criticisms that its plate more than runneth over, the FDA is taking part in the nation's fight against bioterrorism. The agency's National Center for Toxicology Research (NCTR) said it is working on a way to detect toxic biological agents that is cheaper than DNA testing and can rapidly run tests for a series of pathogens.

By combining a process known as pyrolysis with the use of mass spectrometry, the agency will drop a layer of security over the U.S. food supply as well as provide military and domestic enforcement groups with a powerful method of detecting organic compounds.

Pyrolysis is the chemical decomposition of organic materials by heating in the absence of oxygen or any other reagents/ Mass spectrometry is, of course, a means of identifying an atom by ionizing it and measuring its response to a magnetic field as the atom is accelerated through a chamber.

The use of pyrolysis allows a spectrometer to measure organic molecules by heating the molecule so that it emits gaseous matter, then measuring the reaction of those gases to an electromagnetic field.

Pyrolysis is usually applied in an anoxic environment, but Jon Wilkes, PhD, the agency's lead researcher on this program, told Medical Device Daily that while it is currently working the test media in an oxygen-deprived space, it also has run some tests "at atmospheric pressure with air in the vicinity and appear to get acceptable results."

The mere ability to run biochemicals through such a widget will mean little if Customs agents and others don't know what they're seeing. Hence, FDA is working on a parallel effort to build a spectrometer library.

Already in the library are a couple of naturally occurring bacteria, namely Vibrio parahaemolyticus, often encountered in the consumption of oysters, and Salmonella enterica, the bane of anyone unlucky enough to consume bad poultry. At present, this method is not practical for virus detection.

Wilkes said that while the library of bacteria is expanding, the going is slow because "a real-world sample would likely not be one of the exact types we have in the library." And so a field test that results in a near hit might call for further tests, partly because most bacteria come in more than one strain. To compile an exhaustive library, he said, "you would need a library with examples of at least a thousand different bacterial strains, pathogens and non-pathogens."

This technique cannot distinguish between live and dead microorganisms, but the cost compares nicely with that of DNA testing. The latter sports a price tag of $15 to $50 for each sample analysis, whereas spectrometric analysis runs as little as $2 a pop.

Wilkes said the agency hopes to roll this program out "in the near future," but that he and his colleagues are working on a different platform that "works by sampling pyrolysis vapors directly from atmospheric pressure." This new configuration will speed up sampling times from seven minutes to five to 30 seconds. "It's worth the wait, especially if you imagine putting one of these systems" into a metropolitan subway station.

'07 device user fees roll out on schedule

The FDA has formally posted its medical device user fee schedule for FY07, and the numbers offer no pleasant surprises for an industry already disenchanted with the user fee program. The increase was scheduled when Congress passed the Medical Device User Fee Stabilization Act last year.

Full PMA fees for small businesses, those grossing less than $30 million per annum, will jump from just under $99,000 to $107,008. For the deeper of pocket, the increase is from $259,600 to $281,600. Fees for 510(k) applications will bump up from $3,066 to $3,326 for small businesses and from $3,833 to $4,158 for their larger brethren. Similar increases are seen for a variety of other actions: 180-day supplements, panel-track supplements and real-time supplements.

The agency reminds industry that time is of the essence. The federal register notice says that "the latter of the date that the application is received in the reviewing center's document room or the date that the check is received by US Bank determines whether the fee rates for FY 2006 or FY 2007 apply." However, the notice also states that "it is helpful if the fee arrives at the bank at least one day before the application arrives." US Bank has to let the agency know within one day of its receipt of fees.