PrepAhead: how to master your time with GERSTEL Maestro software

Importance of the Topic

In modern analytical laboratories, efficient sample preparation is critical to maximize instrument uptime and ensure data quality. Automated workflows such as dynamic headspace GC-MS, online derivatisation for metabolomics, and LC-UV analysis often involve lengthy incubation or reaction steps. The PrepAhead function in GERSTEL Maestro software addresses these challenges by overlapping preparation steps with the analysis of the previous sample, reducing idle time and preserving sample integrity.

Objectives and Overview

This application note demonstrates how the PrepAhead feature can be applied to three representative workflows:

• Dynamic Headspace GC-MS analysis of Parkinson’s disease skin swab samples
• Online MOX-TMS derivatisation for untargeted metabolomics of biological specimens
• Automated tablet extraction and LC-UV quantification

Each example highlights time savings, instrument utilization, and maintenance of analyte stability.

Instrumentation

The PrepAhead workflows were implemented on a GERSTEL MPS xt Dual Rail (or Dual Head) autosampler platform equipped with various modules:

• Headspace Trapping: GERSTEL DHS module, thermal desorption unit
• Online Derivatisation: MultiPosition Vortexer (mVorx), Evaporation Station (mVAP), CF-200 Robotic Centrifuge
• LC Sample Handling: Stainless Steel Injection Valves, modular wash station
• Analytical Systems: Agilent 7890/1260 GC or LC systems with MSD 5977BC/5975C or DAD detectors

Methodology

PrepAhead enables overlapping of all sample preparation stages (incubation, derivatisation, centrifugation, dilution, trapping) with the chromatographic run of the preceding sample. Typical procedures:

• DHS-GC-MS: 5 min incubation at 60 °C, 500 mL purge at 50 mL/min, trap at 40 °C, followed by a 31 min GC-MS run.
• MOX-TMS Derivatisation: 90 min methoximation at 30 °C, 30 min silylation at 37 °C, centrifugation, then 45 min GC-MS analysis.
• Tablet Extraction LC-UV: sequential vortexing, centrifugation, dilution and mixing steps, followed by a 20 min LC-UV gradient.

Main Results and Discussion

The application of PrepAhead yielded substantial reductions in batch processing times:

• Skin swab DHS-GC-MS: reduced by ~2 h 30 min for 10 samples.
• MOX-TMS metabolomics: decreased from >29 h to just over 10 h for 10 samples.
• Tablet LC-UV: shortened from 9 h 31 min to 6 h 37 min for 10 samples.

By synchronising preparation and analysis, the system maintains freshly prepared samples and minimizes degradation or artefact formation.

Benefits and Practical Applications

The PrepAhead approach offers:

• Enhanced instrument throughput and reduced operator downtime
• Improved data quality by ensuring minimal delay between preparation and injection
• Scalability for high-throughput and QA/QC environments

Future Trends and Opportunities

Emerging developments may include integration of intelligent scheduling algorithms, expansion to diverse analytical platforms (e.g., LC-MS/MS), and adaptive workflows driven by real-time sample feedback. Such enhancements could further optimize resource utilization and instrument performance across research and industrial laboratories.

Conclusion

GERSTEL Maestro’s PrepAhead function significantly improves sample throughput while maintaining analytical integrity. By overlapping preparation and analysis steps, laboratories can achieve up to 60 % reduction in total batch time and ensure consistently fresh sample handling. This feature is readily adaptable to a wide range of automated workflows, offering tangible benefits for both routine and high-complexity applications.

Reference

Technical note no. AS189