Agilent 7696A sample prep workbench

Importance of the Topic

Consistent and precise sample preparation underpins the reliability of chromatographic analyses. Manual workflows introduce variability, increase rework, consume more consumables, and expose analysts to hazardous chemicals. Automating these tasks enhances data quality, laboratory safety, and operational efficiency.

Objectives and Overview

This document presents the Agilent 7696A sample preparation workbench, a standalone automated system designed to standardize key preparatory steps such as dilution, extraction, standard addition, and derivatization. It aims to reduce analyst‐to‐analyst variability, minimize hazardous solvent exposure, and deliver samples ready for direct GC and LC analysis in 2 mL vials.

Methods and Instrumentation

The Agilent 7696A workbench integrates:

• Liquid handling towers for accurate dispensing and transfer across small volumes
• Capability for liquid–liquid extraction, reagent and standard addition, dilution/aliquoting, heating/mixing, and barcode reading
• Single‐position heater (25–80 °C) and optional Peltier cooling (5–40 °C) for temperature control
• High‐capacity trays accommodating up to 150 vials (2 mL) and compatibility with GC/LC autosamplers via transferable well‐plate racks
• Intuitive drag‐and‐drop software with Resource Manager, Method Editor, Easy Sequence, and Dilution Wizard modules
• Integration with fume hoods to protect users from chemical exposure

Main Results and Discussion

Automated linear dilution by the 7696A demonstrated tighter reproducibility across calibration levels compared to manual pipetting. In biodiesel glycerin analysis (EN14105:2011), automated derivatization and quenching routines yielded chromatograms with superior peak precision for free and total glycerins as well as monoglyceride standards. Time‐to‐result for calibration curve preparation was reduced, and written records of each step improved traceability.

Benefits and Practical Applications

• Enhanced reproducibility minimizes costly rework and improves method validation
• Reduced solvent and consumable use lowers operational costs and environmental impact
• Barcode tracking and integrated software ensure full traceability of samples and reagents
• Direct compatibility with GC, LC, GC/MS, and LC/MS auto‐samplers streamlines workflow
• Template‐based methods allow non‐specialist operators to perform complex preparations reliably

Future Trends and Opportunities

Advances in lab automation and digital connectivity point toward fully integrated sample‐to‐result platforms. Potential developments include AI‐guided method optimization, expanded on‐deck capabilities (e.g. centrifugation, evaporation), deeper instrument interoperability, and real‐time process analytics that further reduce human intervention and accelerate decision making.

Conclusion

The Agilent 7696A sample prep workbench offers a robust solution to the inherent variability of manual sample preparation. By combining precise automation, comprehensive software controls, and established chromatographic expertise, it delivers consistent, safe, and efficient workflows that enhance data quality and laboratory productivity.

Used Instrumentation

Agilent 7696A sample preparation workbench with integrated temperature control modules, liquid handling towers, barcode reader, and dedicated method‐development software.