Streamlining Current Approaches for Extractable Analysis Utilizing Waters MV-10 ASFE and ACQUITY UPC2 Systems

Significance of the topic

Extractable compounds released from pharmaceutical and food packaging materials can pose safety, quality, and regulatory risks. Robust analytical workflows are essential to detect a broad polarity range of additives and potential contaminants to ensure product integrity and consumer safety.

Objectives and Study Overview

This application focused on comparing three extraction techniques—Soxhlet, microwave, and supercritical fluid extraction (SFE)—for four common packaging polymers: high-density polyethylene (HDPE), low-density polyethylene (LDPE), ethylene vinyl-acetate (EVA) and polyvinyl chloride (PVC). The extracted samples were screened for 14 polymer additives using UltraPerformance Convergence Chromatography (UPC 2) coupled with photodiode array (PDA) and single quadrupole detection.

Methodology and Instrumentation

• Sample preparation: Polymer samples were cut into 1×1 cm pieces (2–5 g per run).
• Soxhlet extraction: 175 mL of hexane or isopropanol for 8 h, solvent reduced and reconstituted to 15 mL.
• Microwave extraction: 10 mL of hexane or isopropanol at 50 °C for 3 h, no concentration step required.
• Supercritical fluid extraction (SFE): Waters MV-10 ASFE system using CO₂ with low (0.10 mL/min) or high (1.0 mL/min) isopropanol co-solvent at 300 bar and 50 °C, dynamic/static cycles, final volumes adjusted by evaporation or dilution.
• Chromatographic analysis: Waters ACQUITY UPC 2 with BEH 2-EP column (3.0×100 mm, 1.7 μm), 1:1 methanol/acetonitrile modifier, 2 mL/min, 5.1 min runtime, PDA at 220 nm, SQD MS 200–1200 m/z, Empower 3 software.

Main Results and Discussion

• Extraction time: Soxhlet (8 h/sample), microwave (3 h for up to 16 samples), SFE (2 h/sample, up to 10 samples in parallel).
• Solvent usage: Soxhlet (175 mL), microwave (10 mL), SFE (5–30 mL depending on co-solvent level) with 80–97% solvent savings versus Soxhlet.
• Extractable profiles: SFE matched or exceeded Soxhlet in compound recovery and detected greater levels than microwave, especially for PVC.
• Co-solvent flexibility: Adjusting IPA percentage in SFE fine-tuned analyte extraction across diverse polymers.

Benefits and Practical Applications

Supercritical fluid extraction offers significant reductions in solvent consumption, extraction time, and manual intervention. Automated method development in MV-10 ASFE supports quality-by-design studies by varying co-solvent type, concentration, and extraction cycles. Combining SFE with UPC 2 streamlines extractables screening workflows in pharmaceutical and packaging laboratories, improving throughput and environmental sustainability.

Future Trends and Opportunities

Advances in SFE automation, multi-solvent co-solvent control, and integration with high-resolution mass spectrometry will expand detection sensitivity and structural elucidation. Emerging green solvents and miniaturized extraction vessels may further reduce waste. Data-driven method optimization using machine learning could accelerate QbD approaches and regulatory compliance.

Conclusions

SFE on the Waters MV-10 ASFE system combined with ACQUITY UPC 2 detection delivers comparable or better extractables coverage than traditional techniques while achieving 75% time and up to 97% solvent savings. Automated co-solvent optimization and rapid analysis support efficient, environmentally responsible workflows for extractables studies.

References

1. U.S. FDA. Containers Closure Systems for Packaging Human Drugs and Biologics; CDER/CBER Guidance; Rockville, MD; May 1999.
2. Norwood DL, Fenge Q. Strategies for Analysis of Pharmaceutical Excipients and Trace Impurities. Am Pharm Rev. 2004;7(5):92–99.
3. Ariasa M et al. Fast Supercritical Fluid Extraction of Polyethylene Additives: Comparison with Reflux and Automatic Soxhlet. J Supercrit Fluids. 2009;50:22–28.
4. Cabovska B, Jones MD, Aubin A. Application of UPC 2 in Extractables Analysis. Waters App Note 720004490EN. Nov 2012.