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Authors: Xiaohui Zhang, Guotao Lu Study summary: CDS Empore™ SDB-RPS Solid Phase Extraction disks facilitate rapid and reliable sample preparation and provide excellent analyte recovery for hydrophilic compounds with clean chromatograms. A validated EPA Method 8141B workflow extracts organophosphorus (OP) pesticides from 1 L ground water samples spiked at 5.0 ppb using a 47 mm SDB-RPS disk, with GC/MS quantification. Across the 24 compounds listed in EPA Method 8141B, average recovery was...

Authors: Michael Apsokardu, Xiaohui Zhang, Guotao Lu Study summary: CDS Empore™ Oil and Grease (O&G) Solid Phase Extraction disks facilitate reliable sample preparation and provide excellent analyte recovery. This application note demonstrates the performance of the disk under EPA Method 1664 while reducing the total volume of n-hexane by 40% — from 80 mL to 50 mL per sample. Combined recovery of hexadecane and stearic acid from 1 L water samples was 85% with 8.0% RSD at the reduced volume,...

Authors: Guotao Lu Study summary: A validated solid-phase extraction (SPE) workflow using the CDS Empore™ 47 mm C18 SPE Disk extracts 16 PAHs from 100 mL aqueous samples per the U.S. EPA Quick Turnaround Method (QTM). After methylene chloride elution, anhydrous sodium sulfate drying, and nitrogen concentration to 1.0 mL, PAHs are quantified by GC-FID. Validated in groundwater from hazardous waste sites at two spike levels: 200 ppb (n=6, average RSD 5.9%) and 20 ppb (n=3, average RSD 6.2%),...