Flash-VASE™ provides for precise analysis of VOCs & SVOCs in matrices with low volatility.
- Flash-VASE Workflow2
- Flash-VASE Equipment3
- Compare Technique4
- Sample Data5
- Application Notes6
Flash-VASE. What Is It?
Flash-VASE is a next generation Thermal Extraction technique that places the sample in very close proximity to the collection sorbent, and uses static extraction under vacuum to more efficiently and completely recover volatile through semi-volatile compounds. Flash-VASE places the sample within 1-2 cm of the collection sorbent, with no flowing gases to heat up the sorbent during the extraction process like with dynamic headspace techniques, so the collected compounds stay optimally close to the front of the sorbent bed for very fast release to the GC. Extraction under a vacuum allows recovery of chemicals at a lower temperature, reducing or avoiding breakdown of the matrix itself. Flash-VASE has a tremendous number of advantages over other thermal extraction techniques, allowing Chemists to truly “See What’s Really There™”, in a way that keeps the analytical system clean and free from carryover.
Flash-VASE is intended for samples containing relatively low moisture levels, as the sample is heated anywhere from 30° C to 280° C while in a closed system, so the potential for generating a substantial amount of vapor during Thermal Extractions should be considered. However, some excess water can be temporarily delivered and condensed on the Sorbent Pen, as post extraction cold tray cooling of the vials can be performed to transfer the moisture back into the bottom of the vial while still under vacuum, and prior to removal of the Pens from the vacuum extraction sleeves.
The Flash-VASE module can be altered to perform MA-VASE (Matrix Accelerated VASE) which performs a “reflux in a vial” under vacuum to further accelerate the transfer of organics into the gas phase. Just a few additional components allows both techniques to be performed using a single module, supporting a very wide range of sample types. See the MA-VASE TID for more information on this exciting and complementary technique.
How Flash-VASE Improves Thermal Extraction
Flash-VASE utilizes a specialized sample enrichment device called a Sorbent Pen™.
Extensive Number of Applications
The list of Flash-VASE applications is quite extensive, and this technique can be scaled up to look at outgassing from larger samples as needed, such as in forensic investigations of accelerants in fire debris. Just as in VASE, the presence of a vacuum increases the rate of evolution of volatiles out of materials at lower temperatures, and depending on the matrix or sample surface area, the extraction times can be as short as 2-5 minutes (Cannabis) by heating the sample to 100°-200° C under vacuum. This provides a whole new opportunity for high-speed sample throughput for Flash-VASE compatible applications.
Extreme Precision, By Design
Flash-VASE provides incredibly reproducible results, by eliminating the inconsistencies inherent in dynamically purged Thermal Extractions. Below is an example of 8 replicate Cannabis analyses for Monoterpene and Sesquiterpene profiling, and these 8 runs almost perfectly overlap. The Flash-VASE extraction times in these examples was just 5 minutes, at 100° C. Higher temperatures will yield reproducible recovery of the Cannabinoids present in Cannabis