Optimization of sample preparation techniques for the analysis of small molecules (SPE, SPME, SPDE, ...)
Microextraction techniques represent a simple, cost effective and rapid alternative to conventional extraction protocols like, liquid-liquid and solid phase extraction. One of the most important advantages of microextraction is their suitability to be integrated with hyphenated techniques like GC/MS and LC/MS. Solid phase microextraction methodologies (SPME) are well known to be robust, inexpensive and time saving and have found several applications in fields like metabolomics, drug monitoring and related fileds. More recently, new techniques like, solid phase dynamic extraction (SPDE) and micro extraction by packed sorbent (MEPS) had emerged based on the original SPME technology. Furthermore, the coupling of gas and liquid chromatographs to mass spectrometry devices together with the development of liquid handling robots have made possible full automation of all the steps involved in extraction and analysis of target compounds. By using commercially available state of the art instruments and solid phase microextraction techniques, it is possible to carry on enrichment, derivatization and analysis of target compounds with minimal and, in some cases, no human handling. Even more, the combination of modern mass spectrometers with high selective mass analyzers, more sensitive mass detectors and compound libraries have made feasible the determination of analytes of interest at trace level with high confidence.
Figure 1: Schematic diagram of a SPDE device showing relevant method parameters.
Further development of novel microextraction techniques, as well as, optimization and application in routine analysis of commercially available microextraction devices represent a relatively unexplored field. In our opinion more and more routine applications will use such as techniques prior to hyphenated techniques in the future. The present project concentrates on microextraction and automatization as robust alternatives to conventional sample preparation procedures. The application of commercially available microextraction devices, as well as, development of new alternatives to carry on microextraction to assure high throughput analytical data is our main research goal. Small molecule analysis in fields of metabolomics and drug monitoring are of particular research interest. Nevertheless future routine and diagnosis applications are envisioned. Aspects like method validation and accreditation in accordance with the ISO 9001 norms are also considered as important milestones in achieving robust technologies suitable to be applied in routine analysis.
