Broader Adoption of SPE in Environmental Applications Enabled by Selective SPE Chemistries. Kory Kelly and Allen Misa

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1 Broader Adoption of SPE in Environmental Applications Enabled by Selective SPE Chemistries Kory Kelly and Allen Misa

2 Environmental Monitoring Still evolving - New emerging harmful pollutants - New sources of pollutants - Greater need for: - More versatile sample preparation for wider range of analytes - More targeted extraction of analytes - More demanding regulatory requirements: - Improved LOQ and LOD - Higher throughput ability Will require innovative solutions and support

3 Separation Technology Advancements - Use of more sophisticated instruments - Open new possibilities for environmental monitoring - Greater ability to detect previously undetectable harmful toxins and pollutants - Separation advancement not limited to instruments - Use of unique SPE chemistries allow improved analytical capability

4 Sample Preparation - Clean up and removal of interferences - Concentration of target analytes - Solvent switching capabilities - Specifically extract targeted compound - Improve system and instrumentation lifetime - Improve analytical results

5 Sample Preparation Technique Liquid-Liquid Extraction Benefits - Non-specific technique, could be useful when analyzing a wide range of compounds - Easy procedure Challenges Low recoveries (emulsions) Contamination Signal to noise Instrument maintenance Labor intensive Large solvent usage/disposal (hazardous) Application challenge drives us to move beyond traditional approaches to increase productivity

6 Sample Preparation Techniques Supercritical Fluid Extraction Microwave Assisted Extraction Soxhlet ASE Challenges - High cost instrumentation + cost per sample - Poor selectivity - Extensive glassware and vessels to wash

7 Sample Preparation Techniques Selectivity Solid Phase Extraction (SPE) Chemistry is still KING In the field of separation science Solid Phase Extraction Benefits Superior cleanup due to selective sorbent chemistry Higher recoveries of key analytes Greater reproducibility Concentration of key analytes

8 Solid Phase Extraction (SPE) Chemistry Historic uses in EPA and environmental samples - Silica Based Stationary Phases - C18, C8, Phenyl, Si, NH2, IEX, Florisil - Narrow range of particle and sorbent mass/volume selection - Benefits were not compelling enough to justify the change - Throughput - Limited versatility - Limited selectivities

9 Advancements in SPE Chemistries Versatile SPE Sorbents Wide range capabilities Greater ability for stronger wash steps for cleaner extracts Targeted Selectivies Ability for specific targeted extractions Higher recoveries

10 Versatile SPE sorbents Wide range capabilities Strata -XL Large particle, wide pore reversed phase functionalized polymeric sorbent that provides strong retention of neutral, acidic, or basic compounds under aggressive, high organic wash conditions. Ideal use for High volume high flow samples. Strata-XL-A Strata-XL-AW Strata-XL-C Strata-XL Strata-XL-CW

11 Diquat/Paraquat extraction from water Previous Challenges Widely used Herbicide EPA calls for a C8 SPE phase using an ionpairing agent. Ion-pairing methods tend to be irreproducible, leading to variable and inaccurate results Silica SPE phase is not dry resistant- requires more attention during loading Loading can be a slow, long process Overall, method is unreliable

12 Diquat/Paraquat extraction from water Strata -XL-CW Advantages With new method, predominant interaction is ionexchange Also have retention mechanism by RP from the polymeric SDVB backbone Sorbent tested to demonstrate required ionic capacity for ion exchange- extremely consistent from batch-tobatch Polymeric sorbents are dry resistant- no need to monitor loading Large particle sorbent for much faster flow & loading Overall, a much more robust & reproducible method

13 Endothall extraction from water Previous Challenges Widely used Herbicide Per EPA 548.1, bulk anion exchange resin is hand-packed by user Labor & time intensive Hand packing introduces variability Inconsistency packing from user-to-user Ion exchange that was recommended was not ideal Works for DI water with no ions Presence of other ions requires EDTA treatment Poor recoveries, inaccurate & irreproducible results (high RSD%) Endothall Matrix Recovery (%) De-ionized Water 75 Tap Water Tap with Ca + Sulfate <10

14 Endothall extraction from water Strata -XL-A Advantages Pre-packed SPE tubes with Strata-XL-A sorbent time savings Reliable tube & packing consistency ISO-certified QC process to ensure quality & process conformity Optimized material for higher extraction efficiencies, flow, and reproducibility Consistent high recoveries No need for EDTA Establish more robust method Matrix Suggested Material * Strata-XL-A De-ionized Water Tap Water Tap with Ca + Sulfate < * Data taken from method validation data provided with method 548.1

15 Targeted Selectivites in SPE Unique Sorbent Chemistries Extractable Petroleum Hydrocarbons Tests for the presence of gasoline or fuel oil in drinking water. These tests provide information needed to determine if drinking water supplies near petroleum spills are contaminated with petroleum above health-based guidelines. Polycyclic Aromatic Hydrocarbon Polycyclic aromatic hydrocarbon compounds (PAHs) resultant from fire and fuel burning are effectively extracted from water samples while humic acids, which often interfere with chromatographic separation, are removed from the sample

16 Application Challenge Extractable Petroleum Hydrocarbons Total Petroleum Hydrocarbon (TPH or EPA 8015) Application Goal Reproducible fractionation of aliphatic and aromatic hydrocarbons General Purpose Solution Silica-Gel SPE Tubes Challenges to Overcome- Productivity Thieves Irreproducible fractionation Time-consuming Phthalate contamination

17 Application-Specific Solution Extractable Petroleum Hydrocarbons- Overcoming Challenges General Purpose Challenges Irreproducible Fractionation Time-Consuming Phthalate Contamination Application-Specific Solution Refined SPE material Increased flow rate PTFE coating Contamination Level of BHT from Strata EPH and Conventional SPE Tubes General Purpose Silica Gel

18 Application-Specific Advantage Extractable Petroleum Hydrocarbons Strata EPH SPE Tubes: Decreased plasticizer contamination such as BHT Provide fast, consistent flow rates Maintains consistent recovery and efficient fractionation Reduces processing time from 50 min to only 26 min. Translates to 100 % increase in productivity +2x more samples to be processed each hour over a general purpose alternative

19 Application Challenge Polycyclic Aromatic Hydrocarbons (PAHs) Application Goal Deliver consistent recoveries of PAH compounds when extracted from water Application challenge drives us to move beyond general purpose technologies to increase productivity General Purpose Solution C18 SPE Sorbent Challenges Productivity Thieves Humic acid interference Poor recoveries

20 Application-Specific Solution Polycyclic Aromatic Hydrocarbons (PAHs)- Overcoming Challenges General Purpose Challenges Humic acid interferences Poor recoveries Application-Specific Solution Isolate with targeted selectively Optimized sorbent chemistry

21 Application-Specific Advantage Polycyclic Aromatic Hydrocarbons (PAHs) Strata PAH SPE Tubes SPE sorbent that targets PAHs and simultaneously removes humic acids from the sample PAHs can then be eluted while humic acids remain bound in the sorbent Delivers cleaner extracts and also higher recoveries of PAHs as compared to the EPA method general purpose approach

22 Selective SPE chemistries Unlocks GC/MS and LC/MS Advancements Innovative Sorbent Advancements Increased possibility of detection of previously undetected harmful toxins and Pollutants Higher sensitivity Flexibility for greater screening and targeted analysis Improved Productivity Quality results (Specific extraction) Reduce sample preparation method development and troubleshooting Increases instrumentation lifetime

23 Application Specific Support On-Site Lab Demos Environmental Testing Web Page Environmental Edge Newsletter Technical Notes SPE Method Development Tool Digital Learning Tutorials Search Thousands of Application Notes Thank You! For Questions