NEMC: Recent Advances in Sample Preparation by a New Accelerated Solvent Extraction Technique

Significance of the topic

Sample preparation is often the rate-limiting step in analytical workflows, requiring extensive manual handling, solvent consumption and labor. Recent advancements aim to reduce bottlenecks, lower costs, improve reproducibility and enable true walk-away operation in laboratories across environmental, food, pharmaceutical and industrial sectors.

Objectives and study overview

This work presents a next-generation accelerated solvent extraction (ASE) platform that integrates gas-assisted extraction, multi-channel parallel processing and fully automated concentration with intelligent end-point detection. Key goals include reducing solvent usage, increasing throughput, enhancing method control and simplifying workflows from extraction through sample vial ready for analysis.

Methodology and Instrumentation

The platform comprises three core modules:

• Gas-Assisted Extraction: Alternating pulses of solvent and compressed nitrogen circulate through a heated, pressurized cell. Flow rate, pressure and segmentation timing are precisely regulated to maximize analyte solubilization while minimizing solvent volume (US Patent 9,440,166 B2).
• Automated Parallel Extraction: Four independent extraction ovens allow simultaneous processing of up to four cells under identical or varied conditions for higher throughput and flexible method development (US Patent 11,123,655 B2).
• Fully Automated Concentration: Direct coupling of vacuum and nitrogen to collection vials equipped with image sensors. Machine learning algorithms detect the solvent front and trigger an end-point stop to concentrate extracts to a set volume, eliminating manual monitoring.

Key results and discussion

Gas-assisted extraction trials on lipid-rich matrices demonstrated recoveries exceeding 96 % with solvent consumption reduced by ~35 % compared to traditional ASE. A four-channel setup achieved a combined extraction and evaporation throughput of 48 samples per 24 h, outperforming conventional automated workflows (36 samples/day). Validation on soil samples spiked with polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) yielded high recovery rates with excellent reproducibility, confirming the system’s robustness.

Benefits and practical applications

• Significant solvent savings and lower disposal costs
• True walk-away operation reducing hands-on time and error risk
• High throughput via parallel extraction and integrated evaporation
• Enhanced method development through precise control of flow, pressure and temperature
• Direct collection into autosampler vials streamlining downstream analysis
• Smart end-point detection ensures reproducible concentrate volumes

Future trends and potential applications

Integration with laboratory information management systems (LIMS) and advanced data analytics will further streamline workflows. Expanding machine learning models to classify sample composition and predict optimal extraction parameters promises to personalize methods for diverse matrices. Scaling channel counts and solvent blending capabilities can address emerging needs in high-throughput screening and regulated quality-control laboratories.

Conclusion

The presented ASE platform combines gas-assisted extraction, parallel processing and intelligent concentration to deliver major gains in efficiency, reproducibility and solvent economy. It addresses key challenges in modern sample preparation and lays groundwork for fully automated, data-driven workflows.

Reference

• Shevlin C. Recent Advances in Sample Preparation by a New Accelerated Solvent Extraction Technique. NEMC 2022.
• US Patent 9,440,166 B2: Segmented Gas-Assisted Extraction.
• US Patent 11,123,655 B2: Multi-Channel Parallel Extraction System.