The Biomedical Sensors Laboratory has is furbished with some of the latest electronic nose instrumentation currently available as well as more tradtional gas analysis equipment. We work closely with a number of different electronic nose instrument suppliers as well as other gas analysis suppliers. The biosensors laboratory has CL1 biohazard classification to allow the analysis of a range of biological materials. Below are details of some of the current commercial electronic nose and gas analysis equipment available within the BSL.
AlphaMOS Fox Electronic Noses
The Biosensors Laboratory has three Alpha-MOS electronic nose instruments (Fox 4000 and two Fox 3000). Alpha-MOS was originally a spin out company that came from the fundametal electronic nose research which was undertaken initially at Warwick University. Alpha MOS develops and markets Electronic Nose (E-Nose) instruments to analyze odors and volatile compounds (VOC). In a way similar to human nose, Electronic Noses (E-Noses) allow global analysis of the headspace (volatile compounds) generated by liquid, gaseous or solid samples. These odor analyzers consist of three main parts:
- Sampling system,
- Detection system,
- Data acquisition and processing system.
Alpha MOS has developed various models of odour analyzers that can include various sampling modes:
- Manual sampling
- On-line sampling
This instrument employs an array of gas sensors (Metal Oxide Sensors or MOS) to detect gas phase chemical components within the sample. Data acquisition and processing is achieved through Alpha MOS proprietary software (Alpha Soft) using powerful multivariate statistics and chemometrics. More information on the Fox Electronic nose can be found on the Alpha-MOS website.
Sensigent Cyrano Electronic Nose
The Cyrano electronic nose (first developed by Cyrano Sciences in partnership with Warwick University), is a small, handheld electronic nose. The measurement is based on a change in resistance of each chemical sensor in the 32-sensor NoseChip when exposed to a chemical vapour. This is a differential measurement with the sensor response measured as (Rmax-Ro)/ Ro, with Ro being the resistance during a baseline gas flow and Rmax being the maximum resistance during exposure to the sample vapour.
This instrument employs composite polymer sensors (a combination of a insulating rubber and conducting carbon black, where the carbon endows conductive properties to the resultant mix). When exposed to a vapour, the polymer swell reducing the number of conductive paths through the sensor and thus increasing its resistance. This change in resistance is then used for pattern recognition software built into the Cyrano.
More information can be seen on the Cyrano Website
Owlstone Lonestar FAIMS
The Owlstone Lonstar FAIMS (Field Asymetric Ion Mobility Spectrometer) employs physical measurement to seperate different chemicals in a complex mixture. In these instruments, the inlet sample is first ionized. This then pass through two plates onto which is applied a asynchronous electric field. The high electric field on one of the plates cause molecules to move either towards, away or not affected by this plate. This movement is due to the fact that some molecules more faster or slower in high electric fields. A compensation volatage is also added to balance out the effect of this electric field. By scanning through a range of different electric fields and compensation voltages, it is possible to seperate a range of different chemical components.
More details of this instrument can be found on the Owlstone Website.
1st Detect MS/MS
We currently have available the only 1st Detect portable mass-spectrometer in Europe, the MMS-1000. This air based instrument is able to do MS/MS analysis using air as the carrier gas and is portable/battery powered. This instrument is currently being assessed for its use in a range of different application areas.
The instrument is augmented with a pre-concentrator system, which allows PPB/PPT sensitivity.
- Mass Range: 45 – 400 amu (standard)
- Custom ranges over 15 amu to 500 amu available
- Resolution: Better than Unit Mass Scans/Sec: 1 spectra/sec (typical) 7 spectra/sec (maximum), with 14 TIC points/sec. Faster scan rates require special settings.
- Sensitivity: (measured at m/z = 91 amu xylene) Membrane Inlet 500 ppb, Preconcentrator 500 ppt using 30 sec sampling time
Weight: < 8 kg
- Size: 19 cm x 33 cm x 23 cm
- MS/MS Capable: No collisional gas or buffer gas required
More details on this system can be found at the 1st Detect webpages
AIRSENSE Analytic PEN3 Electronic Nose
In addition, to our other commercial electronic noses, we are also fortunate to have a AIRSENSE Analytic PEN3 instrument. It is based on a metal-oxide gas sensor array. It has a unique dilution technique to provent overloading with substances. This extends the life time of the sensors and shortens the cycle times. This gas-flow control makes it possible to stabilize the pattern under varying concentrations and analytical conditions. Individual gases or gas mixtures are classified and recognized by a pattern recognition technique. In this case, the unit provides a quick and simple quantitative answer as good or bad, yes or no ...
- Sensor array 10 different metal oxides single thick film sensors, optional adapted to application
- Sensor response time typical: less than 1 second Inlet Sampler special fluidic connector
- Sample flow adjustable, 10ml/min to 400ml/min Flow system internal pumps, internal sample dilution system
- Measurement time depending on the application from 4 seconds to some minutes typical: 1 minute (20s measurements, 40s zero gas)
- Sensitivity LOD 0.1 to 5ppm for gases and organic solvents, e.g. 0.1ppm H2S Display graphical display
- Dimension 255 x 190 x 92 mm Weight 2.1 k
More details can be found on the AIRSENSE website.
Gas Chromatograph / Mass Spectrometer
In addition to the range of electronic noses available in this laboratory, we also have our own dedicated GCMS instrument to detect and indentify specific chemicals within our samples. The lab has a latest generation Scion Instruments SQ GCMS fitted with a Markes Interational Unity-xr automated thermal desorbtion system.