Revolutionizing SPE with Otto SPEcialist: An Easy-to-Use, Software-Driven, Positive Pressure Manifold

Importance of the Topic

Solid-phase extraction (SPE) is a pivotal step in forensic and bioanalytical workflows, enabling efficient extraction, purification, and concentration of target analytes prior to instrumental analysis. Consistency and reproducibility in SPE protocols are essential to minimize errors and improve throughput.

Study Objectives and Overview

This study compares the semi-automated Waters Otto SPEcialist positive pressure manifold with the fully automated Hamilton Microlab STAR vacuum-based system. The aim is to assess recovery performance, precision, and ease of use when extracting controlled drugs from spiked urine samples.

Methodology and Applied Instrumentation

A panel of 21 drugs was spiked into pooled urine at low (50 ng/mL) and high (1000 ng/mL) concentrations. Samples were processed across three batches over three days with quadruplicate replicates. For the Otto SPEcialist, a software-driven positive pressure ramp controlled flow through Oasis MCX sorbent beds, while wash and elution steps were added manually. The Hamilton STAR performed all liquid handling and SPE steps automatically under vacuum. Instrumentation included:

• Otto SPEcialist Positive Pressure Manifold
• Hamilton Microlab STAR Automated Liquid Handling System
• Oasis MCX SPE Sorbent Plates and Cartridges
• ACQUITY UPLC I-Class PLUS System
• Xevo TQ-S Micro Triple Quadrupole Mass Spectrometer
• MassLynx and TargetLynx Software

Main Results and Discussion

Recoveries for the Otto SPEcialist were comparable to the fully automated system, with inter-day recoveries of 85–98% (low) and 89–113% (high) and standard deviations below 7.7% and 3.5%, respectively. Intra-day recoveries ranged from 78–99% (low) and 83–116% (high) with RSDs under 6.6% and 3.3%. These results demonstrate robust performance and reproducibility across multiple days and batches.

Benefits and Practical Applications

The Otto SPEcialist offers:

• Streamlined method transfer and reduced user-to-user variability
• Mitigation of manual errors via software-controlled pressure ramps
• Compact footprint suitable for bench or fume hood placement
• Cost-effective alternative to fully automated systems
• Time savings that allow scientists to focus on other tasks

Future Trends and Opportunities

Emerging directions in SPE automation include integration with laboratory information management systems (LIMS), expansion to diverse sample matrices, and the incorporation of AI-driven protocols for dynamic method optimization. Semi-automated platforms are poised to bridge the gap between manual and fully automated workflows, delivering both flexibility and reliability.

Conclusion

The Otto SPEcialist Positive Pressure Manifold delivers consistent and reproducible SPE performance comparable to fully automated vacuum-based systems while offering a user-friendly interface, reduced cost, and a smaller footprint. This semi-automated approach enhances SPE workflows by minimizing errors and improving laboratory efficiency.

References

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