Solid phase extraction (SPE) is one of the sample preparation methods most widely used by chromatographers, as demonstrated by the numerous published SPE methods found in the literature. Typically, a liquid sample is passed across an adsorbent bed to retain and concentrate target analytes and eliminate interference from the sample matrix. Alternatively, the adsorbent can be used to retain interferences while allowing the target analytes to pass through. Manual SPE cartridge formats can vary from disks through individual cartridges with a range of different volumes to 96-well plates. However, solid phase extraction methods can be tedious and time consuming when performed manually. There is therefore an increasing need for the automation of solid phase extraction methods.
A robotic X-Y-Z coordinate autosampler commonly used for sample introduction in GC or HPLC can be used to perform a wide variety of sample preparation techniques using a single instrument and controlling software. The MAESTRO software allows the user to control the automation of solid phase extraction methods. In addition to ease of use and intuitive windows-based programming, the software includes tools to optimize method parameters ensuring efficient sequence creation and maximum sample throughput. The sampler can be configured as part of a GC or LC system or as a benchtop workstation.
In this study, we show that existing manual SPE methods can be transferred to standard format automation cartridges and automated using the robotic autosampler in conjunction with the software. Examples of solid phase extraction methods illustrating the conversion from manual to automated methods are shown.
