Fully Automated Bioanalytical Solid Phase Extraction Sample Preparation, using Extraction+ Connected Device with the Andrew+™ Pipetting Robot

Significance of the Topic

Solid phase extraction is a vital sample preparation step in bioanalysis, ensuring removal of matrix interferences and reliable quantification of analytes in complex biological samples. Automating this process addresses common sources of variability such as pipetting errors, manual labeling mistakes, and inconsistent extraction conditions, ultimately improving data quality and laboratory efficiency.

Study Objectives and Overview

This application note evaluates fully automated bioanalytical solid phase extraction workflows using the Andrew+ pipetting robot paired with the Extraction plus device. Calibration curve and quality control sample preparation, followed by extraction of pharmaceutical compounds from plasma, were performed in both cartridge and 96 well plate formats. The goal was to demonstrate accuracy, precision, and walk-away capability of the integrated system for LC-MS analysis.

Methodology

Sample preparation involved automated generation of calibration standards (5 to 200 ng/mL for cartridges, 5 to 500 ng/mL for plates) and QC samples at low, mid, and high concentration levels. Extraction employed Oasis HLB sorbent in 1 cc cartridges or 96 well plates with vacuum control managed by the Extraction plus device. After conditioning and loading, samples were washed and eluted with methanol, then diluted prior to LC MS analysis. Chromatography used an ACQUITY UPLC I Class system with 0.1 percent formic acid mobile phases and detection on a Xevo TQ XS triple quadrupole in positive ESI MRM mode.

Instrumentation

• Andrew+ pipetting robot with microplate gripper
• Extraction plus connected SPE manifold and vacuum pump
• OneLab cloud based control and method design software
• ACQUITY UPLC I Class system with HSS PFP column (2.1 x 50 mm, 1.8 micron)
• Xevo TQ XS mass spectrometer operating in ESI positive MRM mode

Main Results and Discussion

Automated workflows yielded calibration curves with linearity above 0.99 and relative standard deviations under 15 percent. Quality control accuracy ranged from approximately 89 to 111 percent, with precision RSDs mostly below 5 percent. Both cartridge and plate formats showed comparable performance, demonstrating robustness and reproducibility of the automated extraction protocols.

Practical Benefits

• Fully walk away operation eliminates manual intervention during SPE
• Consistent vacuum profiles reduce variability in extraction efficiency
• Automated liquid handling minimizes pipetting errors and sample mix ups
• OneLab software simplifies method setup and deployment across formats

Future Trends and Applications

Integration of robotics and smart SPE devices will continue to expand, enabling higher throughput screening and complex sample workflows. Advances in software connectivity and adaptive protocols may allow real time process control and integration with data analytics for predictive maintenance and method optimization.

Conclusion

The combined Andrew+ and Extraction plus system provides a reliable, fully automated solution for bioanalytical SPE preparation in both cartridge and plate formats. High accuracy and precision in calibration and QC samples demonstrate the system’s capability to improve laboratory productivity and data quality in LC MS workflows.

References

• Waters Corporation. Application Note 720007712, September 2022.