Easy and Fast Automation of Sample Preparation

Significance of the Topic

Automated sample preparation addresses the growing demand for high-throughput analysis in research, quality control, and industrial settings. By integrating injector workflows directly into autosamplers, laboratories can reduce hands-on time, minimize human error, and improve data consistency across derivatization, dilution, and calibration tasks.

Objectives and Study Overview

This technical overview evaluates the feasibility and performance of Agilent 1260 Infinity III Multisampler and Vialsampler injector workflows for:

• Precolumn derivatization of amino acids using OPA/FMOC protocols
• Serial dilution for calibration standard preparation (caffeine series)
• Comparison against traditional injector programming

Methodology and Instrumentation

Sample preparation and analysis were performed on an Agilent 1260 Infinity III LC system configured with either a Vialsampler (G7129A) or Multisampler (G7167A). Key components included:

• Binary Pump (G7112B)
• Variable Wavelength Detector (G7114A) and Fluorescence Detector (G7121B)
• Poroshell 120 EC-C18 (2.1 × 50 mm, 2.7 µm) and AdvanceBio AAA columns (3.0 × 100 mm, 2.7 µm)
• OpenLab CDS v2.8 or later for workflow control

Reagents and mobile phases were prepared according to standard protocols for amino acid derivatization (borate buffer pH 8.2, FMOC, OPA) and caffeine calibration (aqueous organic dilution series). Injector workflows were customized via template interfaces, allowing precise control of sample, reagent, and buffer volumes without manual pipetting.

Main Results and Discussion

Amino acid derivatization workflows yielded:

• Retention time RSD<0.1% and area RSD<1% (n=10)
• Limits of detection mostly below 0.4 pmol/µL
• Linear calibration (R²>0.999) for 18 of 20 amino acids; quadratic fits for cysteine and proline

Caffeine dilution series achieved:

• Calibration linearity R²>0.99994
• Control sample deviations <4% (Multisampler) and <1% (Vialsampler)

This demonstrates injector workflows match conventional methods in precision and sensitivity while streamlining method setup and execution.

Benefits and Practical Applications

Implementation of injector workflows offers:

• Reduced manual pipetting and operator dependence
• Rapid method development via user-friendly templates
• Reproducible derivatization, dilution, and calibration across operators and instruments

Suitable applications include amino acid analysis in food and bioprocess monitoring, small-molecule quantification in pharmaceutical QC, and any workflow requiring repetitive sample handling.

Future Trends and Applications

Advancements may include integration of online sample tracking, expansion to multi-reagent protocols, and coupling with AI-driven optimization to further reduce development time. Broader adoption could enable fully unattended sample workflows in regulated environments.

Conclusion

Agilent 1260 Infinity III injector workflows in Multisampler and Vialsampler platforms deliver automated, precise, and sensitive sample preparation for amino acid derivatization and serial dilutions. They reduce labor, ensure consistency, and accelerate method deployment compared to traditional programming.

Reference

1. Schipperges S. Comparison of Plant-Based Meat Alternatives and Meat. Agilent Technologies Application Note 5994-5950EN, 2023.
2. Schipperges S. Let Your Autosampler Do Your Pipetting. Agilent Technologies Technical Overview 5994-1704EN, 2020.
3. Lee KS, Drescher DG. Derivatization of Cysteine and Cystine for Fluorescence Amino Acid Analysis with the o-Phthaldialdehyde/2-Mercaptoethanol Reagent. Journal of Biological Chemistry 1979, 254(14):6248–6251.