Owlstone Medical’s patented FAIMS technology has the ability to rapidly monitor a broad range of VOC biomarkers from breath, urine and other bodily fluids with high sensitivity and selectivity
Owlstone Medical's FAIMS technology provides an extremely sensitive, selective, non-invasive and fast means of identifying VOC biomarkers in breath, urine and other clinical samples. FAIMS instruments are also portable, easy to use and affordable, making them ideal for use in point of care applications.
Medical researchers are already using FAIMS to identify and measure VOC biomarkers related to medical conditions such as cancer, asthma and tuberculosis. Testing for the presence of these tell-tale chemicals allows a new way of diagnosing these diseases early, without the need for costly and invasive medical procedures.
The video above describes FAIMS theory in a little more detail, including an animation of ions travelling through Owlstone Medical's FAIMS device.
How Does FAIMS Work?
Field Asymmetric Ion Mobility Spectrometry (FAIMS) is a variant of ion mobility spectrometry – a method of distinguishing charged gaseous molecules according to differences in the speed that they move through a buffer gas under the influence of an oscillating electric field.
After ionization, the VOC ions pass through channels across which an asymmetric RF field is applied. Under the first portion of the waveform, ions will drift in one direction at a velocity based on their individual mobility in that electric field. As the field polarity is reversed the ions change direction and speed based on the new field conditions. As the mobility of the ions during the two parts of the waveform is rarely equal, there is usually a net drift towards one of the electrodes. In FAIMS, this net drift is corrected for by applying an additional DC voltage, known as the compensation field (CF), focussing specific ions through the device to the detector.
The figure on the left shows three ions, all demonstrating different mobility behaviours under the influence of the electric field. The trajectory of two ions collide with walls, however the trajectory of the third ion has the appropriate DC voltage applied, meaning it traverses the device. The FAIMS device scans these DC voltages, producing a compensation field spectrum for the transmission of all ions.
Research into medical diagnosis using VOC biomarkers has tended to focus on high end analytical techniques such as gas chromatography-mass spectrometry. Unlike FAIMS, these methods are of limited use in clinical settings because they are time consuming and require expensive equipment run by highly trained specialist staff.
FAIMS also has advantages over other techniques for the detection of disease biomarkers. An example would be ‘Electronic Nose’ or eNose technology. These systems use arrays of non-selective chemical sensors. However, eNoses often suffer from stability and sensitivity issues such as poor intra-device repeatability, limited temporal stability and poor chemical selectivity due to unwanted chemical interactions between VOC biomarkers and the sensors. These problems severely hamper the translation of eNose technology from the lab bench to the doctor’s office.
A schematic overview (below) shows the main advantages of Owlstone Medical's FAIMS technology over the main types of medical diagnostic sensor.
FAIMS’ sensitivity allows it to detect VOCs at low parts per billion (ppb) and in some cases part per trillion (ppt) levels making it well suited for detecting VOC biomarkers from clinical samples, which are typically present around the tens of ppb range. The selective nature of FAIMS detection also means that even in a typical breath sample containing hundreds of VOCs unrelated to the disease of interest, it can ignore chemical noise and detect biomarkers of interest with a low incidence of false positives making it ideal for the identification of specific disease biomarkers from complex backgrounds. Additionally, FAIMS instruments have excellent intra device stability, allowing straightforward introduction into clinical settings after an initial validation and the small size and straightforward programmability of the FAIMS chip makes it suitable for near patient or point of care operation.
Detection levels below part per billion (ppb)
FAIMS can target specific disease VOC biomarkers in breath, urine and other clinical samples
The FAIMS chip can be re-programmed in software to detect different VOC biomarkers, depending on the application
The dime-sized FAIMS chip is incorporated into portable instrumentation suitable for point-of-care use
FAIMS can detect disease biomarkers non-invasively from breath, urine and other biofluids
Easy to use
Our instruments are designed to be used by non-specialists
FAIMS can detect VOC biomarkers at a fraction of the price of other techniques, such as GC-MS