Automated Solid Phase Extraction and Direct to Vial Concentration for Dioxin in Water

Dioxins are a group of polyhalogenated compounds which occur as by-products in the manufacture of organochlorides, in the incineration of chlorine-containing substances such as PVC (polyvinyl chloride), in the bleaching of paper, and from natural sources such as volcanoes and forest fires. Aside from being known carcinogens, dioxins and dioxin like compounds have been linked to developmental abnormalities, nervous system, pathology, diabetes, thyroid disorders and damage to the immune system. For these reasons, it is becoming increasingly important to determine dioxin free drinking water and food sources. This procedure demonstrates the use of the FMS PowerPrep SPE and the PowerVap Direct to Vial Concentration system in water samples.
Instrumentation

• FMS, Inc. Power Prep SPE system (Solid Phase Extraction)
• FMS, Inc. PowerVap Concentrator
• Waters Corporation Oasis 1 gram HLB Cartridge
• Thermo Fisher Scientific Polaris Q GCMS

Method Summary

PowerPrep SPE
1. Condition Cartridge with MeOH
2. Condition Cartridge with HPLC grade H2O
3. Load 1 Liter of water sample
4. Rinse container and load rinse volumne
5. Dry Cartridge
6. Elute sample from Cartridge (DCM)

PowerVap Concentrator
1. Pre-heat temp: 70 deg C
2. Pre-heat time: 15 minutes
3. Heat in Sensor mode: 70 deg C
4. Nitrogen Pressure: 15 PSI

Results

Procedure
Four 1 liter water samples were spiked with 100ul of Cambridge Isotopes EDF-4144B Dioxin/Difuran spiking solution. Samples were then loaded onto the FMS SPE system using a vacuum pump and passed across a Waters Oasis HLB cartridge. After loading, samples were then dried using a stream of nitrogen until no residual water was present, and cartridges were subsequently eluted using Methylene Chloride. Extracts were eluted directly into the FMS Power Vap concentrator, spiked with 2 ul dodecane (keeper) and blown to dryness in direct to vial tubes. Samples were then re-constituted to 20 ul nonane and injected onto a GC HRMS system for quantative analysis.

Conclusions
The FMS Power Prep SPE and PwerVap Concentration system has been shown reliable, reproducible results for low level dioxin and dioxin like compounds in drinking water. The use of direct to vial concentration tubes eliminated the need for sample transfer of very low volume extracts and the risk of extract loss.

View the PowerPrep SPE Video
For more information contact FMS www.fmsenvironmental.com