Extraction of Semi-volatile Organic Compounds in Drinking Water with NEW Atlantic® ReadyDisk High Capacity C18 Solid Phase Extraction Disks

Importance of the Topic

Drinking water is a key exposure route for semi-volatile organic compounds that pose potential health risks. Regulatory agencies such as the U.S. EPA rely on robust extraction and analytical methods to quantify trace levels of pesticides, industrial chemicals and polycyclic aromatic hydrocarbons in water supplies.

Objectives and Study Overview

This application note evaluates the performance of the new Atlantic ReadyDisk HC-C18 high-capacity solid-phase extraction (SPE) disk for isolating semi-volatile organics from drinking water. The work follows EPA Method 525.2, assessing accuracy, precision and method detection limits (MDLs) through blank tests, laboratory fortified blanks and replicate analyses.

Methodology and Instrumentation

One-liter drinking water samples were acidified to pH <2, spiked with surrogate and internal standards, then processed on a Biotage Horizon 5000 SPE workstation using Atlantic ReadyDisk HC-C18 disks. Conditioning steps employed ethyl acetate, methylene chloride, methanol and reagent water. Samples were loaded at ~70 mL/min, dried on a Biotage Horizon DryVap with DryDisk membranes, and eluted sequentially with ethyl acetate, methylene chloride and a 1:1 solvent mixture. Extracts were concentrated to 1 mL and analyzed by Agilent 6890 GC coupled to a 5975C MSD, using a ZB-SemiVol column, splitless injection (1 µL), helium flow (1 mL/min) and a temperature program from 60 °C to 320 °C.

Main Results and Discussion

Reagent blanks showed no detectable contamination. In six replicates of fortified blanks (5 µg/L), most analytes achieved recoveries between 70–130% with relative standard deviations under 30%, meeting EPA 525.2 criteria. Notable exceptions included hexachlorocyclopentadiene (27.6%), carboxin (78.6%), atraton (25.3%) and prometon (37.6%) due to degradation, instability or ionization under acidic conditions. MDLs for detected compounds typically ranged from 0.02 to 0.21 µg/L, calculated from replicate standard deviations and Student’s t for a 99% confidence level.

Benefits and Practical Applications

The high-capacity ReadyDisk HC-C18 offers a plug-and-play SPE format that simplifies sample preparation, reduces handling steps and minimizes contamination risk. Its compatibility with automated SPE and evaporation systems enables reliable quantitation of a broad spectrum of semi-volatile organics, suitable for routine environmental monitoring, QA/QC and regulatory compliance in water analysis laboratories.

Used Instrumentation

• Atlantic ReadyDisk HC-C18 solid-phase extraction disks
• Biotage Horizon 5000 SPE workstation
• Biotage Horizon DryVap concentrator with DryDisk membranes
• Agilent 6890 gas chromatograph with 5975C mass selective detector

Future Trends and Potential Applications

Advancements may include integration of SPE disks with on-line GC-MS for real-time monitoring, expansion of SPE chemistries for more polar or emerging contaminants, and application of the workflow to other matrices such as wastewater, groundwater and soil extracts. Continued improvements in automation and miniaturization will drive higher throughput and lower detection limits.

Conclusion

The Atlantic ReadyDisk HC-C18 combined with Biotage automated extraction and concentration platforms delivers accurate, precise and sensitive analysis of semi-volatile organic compounds in drinking water in accordance with EPA Method 525.2, while streamlining laboratory workflows.

References

• US EPA. Method 525.2, Revision 2.0: Determination of Organic Compounds in Drinking Water by Liquid-Solid Extraction and Capillary Column Gas Chromatography/Mass Spectrometry.