Summer School 2022: Automation and miniaturization in sample preparation
Introduction
Automation of extraction procedures significantly saves times and sample handling to increase the throughput and repeatability of analyses while avoiding errors. This course will be organized in 3 days to cover a variety of approaches to sample preparation in the area of environmental analysis as well as the preparation of plant extracts. In case of environmental samples, various lectures and practical tasks will be focused to SPE directly connected (on-line) to LC separations. Two different ways how to connect SPE to LC will be discussed – either column switching directly in the LC system or column switching/heart-cut injection by on-line hyphenation of low-pressure flow approaches. Advantages and drawbacks of both procedures will be discussed. Practical tasks will further cover SPE attempting miniaturization using different nanofibrous polymers such as polyethylene, polyamide, or polycaprolactone for the extraction of pesticides/insecticides or bisphenols.
In the second part of the course, the automation and miniaturization of liquid phase microextraction approaches by flow automation techniques will be explained in a thorough lecture and accompanied by practical demonstration of a Lab-In-Syringe system covering dispersive liquid-liquid microextraction and single drop microextraction including the use of green solvents for this purpose and the use of 3D printing technology for system setup and optimization. The automation of dispersive solid phase extraction by this technique will further be shown.
The third area of extraction will be more focused on the green approach of supercritical fluid extraction (SFE) applicable to lipophilic as well as hydrophilic target analytes. Modification of the extractant with modifiers and variation of pressure and temperature – viscosity and lipophilicity will be tested in practical tasks while via lectures, the principles of SFE, instrumentation, and method development will be explained including limitations and possibilities in case of hydrophilic substances extraction that are mainly present in plant extracts (polyphenolic compounds). In case of this analyte class, SFE provides an alternative way of extraction to classical solvent-based approaches allowing the extraction also of non-stable substances with a minimum risk of decomposition.
Aims
The aims of this course are:
- to extend and increase the theoretical and experimental knowledge based on green sample preparation including on-line SPE, LPME, and SFE techniques as well as on the automation and miniaturization of liquid phase microextraction approaches
- to support confidence of participants to modern extraction methods
- to show and highlight modern advances in sample preparation in a variety of application fields
- to stress modern alternatives of sample preparation in frames of SPE using advanced/smart materials (e.g., nanofiber materials)
- to demonstrate advantages of SFE in extraction of lipophilic or low stability hydrophilic analytes