ATLAS Headspace Sampler
Add simple and reproducible headspace sampling to Lonestar for analysis of VOCs from liquids and solids
- Automated temperature and gas flow control for reproducible detection of VOCs
- Versatile pneumatic operation allows optimisation of settings for detection of target VOCs
- Built in particulate filters protect the Lonestar from sample particles and droplets
The ATLAS module collects the headspace gas above liquid or solid clinical samples and transfers it to Lonestar. A patient’s sample is placed into the heating region (shown in the cutaway diagram) and is then held at a constant temperature to allow equilibration.
Only analytes that diffuse from the sample into the headspace are transferred via a purge flow to the Lonestar for analysis. Clinical sample matrices like urine, stool, saliva, sweat and blood contain non-volatile material alongside the VOC biomarkers. ATLAS allows the selective analysis of volatile biomarkers in these samples.
Programmable temperature control
The ATLAS module can heat the sample bottle to a temperature of up to 60 ± 1 °C
Versatile pneumatic operation
Allows optimisation of gas flow settings for optimised detection of VOCs of interest from different biological matrices.
Built in particulate filters protects the Lonestar from sample particles and droplets larger than 1 µm in diameter
Data acquisition synchronised with headspace purge
Ensures time-dependent data is captured repeatibly
Range of sample vessel options
Different sized sample vessels offers additional means of optimising VOC response
How it works
The ‘headspace’ of a sample is simply the gas space above a liquid or solid specimen. VOCs from the sample diffuse into the headspace gas, which can be analysed to provide information about the chemical composition of the sample, providing a means of non-invasive analysis of patient samples for VOCs related to disease.
The purge flow that carries VOCs from the sample headspace to the Lonestar instrument plays an integral part in the sensitivity of the method, as it reduces the concentration of analyte in the headspace, increasing its rate mass transfer into the headspace. Another important factor is the distance between the purge flow inlet and the surface of the sample. The ATLAS Headspace Sampler offers control over these key parameters, offering a versatile headspace sampling solution for VOC analysis.
The figure on the left shows the factors that influence the final headspace concentration in more detail.
The concentration of VOCs in the headspace is strongly dependent on sample temperature. Once the clinical sample is placed into the ATLAS Module and sealed, ATLAS heats and accurately maintains the sample's temperature, facilitating the reproducible transfer of VOCs into the headspace of the vessel. Concentration of VOCs in the headspace is also dependent on:
- Concentration and vapour pressure of the VOCs in the sample
- The concentration gradient of the analyte between the liquid and headspace, and between the surface of the liquid and the bulk of the liquid.
The ATLAS Headspace Sampler is comprised of four separate components, the Sampling Module Assembly, the Pneumatic Control Box, the Heater Control Box and the Split Flow Box (SFB). An ATLAS Sample Stirrer Module is available when liquid samples are being analysed where stirring of the sample is required.
The system incorporates heated sampling lines to minimise chemical adhesion to transfer tubes and allows headspace sample dilution with a dry gas flow to prevent the masking of lower concentration chemical components by water contained in the samples.
ATLAS technical specifications
Gas supply pressure
40 psi (2bar)
< -45oC dewpoint, < 0.1 ppm hydrocarbons as methane
ATLAS Pneumatic Control Box dimensions
(w) 365 mm x (h) 107 mm x (d) 320 mm
ATLAS Pneumatic Control Box weight
ATLAS Sampling Module Assembly dimensions
(w) 200 mm x (h) 170 mm x (d) 130 mm
ATLAS Sampling Module Assembly weight
ATLAS Heater Control Box dimensions
(w) 365 mm x (h) 95 mm x (d) 320 mm
ATLAS Heater Control Box weight
ATLAS Heater Control Box max output power
ATLAS Heater Control Box max output current
ATLAS Pneumatic Control Box input voltage (with stirrer)
110 or 240V (manually switched)
ATLAS Heater Control Box output voltage
24 V DC ±2.5%
Pneumatic Control Box max input current (with stirrer)
0.07 A @ 240 V, 0.16 A @ 110V