Possibilities for Automation of Sample Preparation Steps prior to HPLC or GC Analysis using a Common Autosampler

Abstract

The primary function of an autosampler for a chromatographic instrument is to provide unattended operation and thereby increase instrument utilization and improve sample throughput in the lab. A second important benefit of autosampler use is the improved reproducibility of analytical results compared to manual injections. Automation of sample preparation steps would have similar benefits in improving sampling reproducibility. This paper describes a software solution to control a common autosampler for HPLC or GC (MPS, GERSTEL) that provides flexible sample preparation capability without purchasing expensive laboratory robots. The following example applications illustrate the flexibility of this software for custom method generation:

  • Addition of internal standard to samples prior to injection.
  • Sample derivatization (esterification) followed by solvent extraction (hexane) and transfer of the extract into autosampler vials.
  • Online process monitoring using time programmed sampling with a flow cell before HPLC analysis.
  • Hexane extraction of chlorinated pesticides in aqueous samples using a membrane extraction device followed by large volume GC injection.
  • Automated GERSTEL Twister solvent back extraction followed by HPLC analysis of PAH’s in aqueous samples.