Patent Filed For "Total Ion Control" Mass Spectrometry Device

Future Mars rovers could have smaller, cheaper and more sensitive life-detecting instruments, thanks to a new invention unveiled by scientists at the U.S. Department of Energy's Idaho National Laboratory (INL).

The INL team has found a new way to generate complex electric fields, which will make it easier to direct ions, or charged particles, along specified paths. The researchers just filed a patent application for their Total Ion Control method, a key advance in the field of mass spectrometry. TIC-based equipment could make the Mars Organic Molecule Analyzer (MOMA) -- part of the ExoMars mission scheduled for launch in 2018 -- a better life-detecting tool.

"This is a novel way to shape electric fields for moving ions around," said INL engineer and TIC co-inventor Tim McJunkin. "It can improve MOMA, and it could improve commercial instruments."

Image Courtesy INL

MOMA, a mass spectrometer, will vaporize and ionize Martian dirt with a laser. The charged particles will flow through an inlet, down a channel and into a trap, where MOMA will scan them for signs of life like amino acids. To get ions into the trap, most mass spectrometers rely heavily on air flow created by pumps. This system isn't ideal for Mars missions, though; pumps are heavy and energy-hungry.

TIC technology could assist MOMA. TIC-based inlets generate intricate electric fields that efficiently guide ions into the trap, greatly reducing the need for pumps.

Image Courtesy INL

Several other technologies attempt to do the same thing, but INL's invention boasts many advantages. First, TIC-based inlets should be cheaper and more robust, because they're simpler to construct and have fewer parts. Other devices that generate elaborate, complex fields tend to be elaborate and complex themselves. They have multiple, precisely configured electrodes, interspersed with insulators. But TIC-based solutions use only a single electrode and don't need insulators. They can be made from many different semi-conducting materials. And the fields TIC inlets generate are incredibly flexible, so they can be incorporated into many spectrometer designs.

Space missions demand low-weight, low-power equipment; INL's invention hits that mark, too. TIC-based inlets weigh less than an ounce, and they require 100 milliwatts of power at most -- 1,000 times less than a 100-watt light bulb.

Image Courtesy INL

INL says its TIC also gathers 10 times as many ions into the trap as commercially available inlets do. Such efficiency is key to MOMA, since any signs of life in the Martian soil will likely be scarce, if they exist at all.

The INL researchers are talking to the U.S. MOMA team about incorporating the technology into MOMA. But the invention could also find many other applications, according to INL scientist and TIC co-inventor Jill Scott. "This is an enabling technology," she said. "If you want to move ions around cheaply and robustly, and without much weight, this is the way to do it."

FMI: www.inl.gov