If you do not know the behavior of your samples or analyte in solid phase extraction, or if you want to optimize an existing extraction procedure, we recommend MACHEREY-NAGEL method development kits. Consisting of a variety of different SPE phases and column formats they are the ideal tool for approaching any analytical task systematically. For the development kits as well as for all individual CHROMABOND, CHROMABOND LV and CHROMAFIX types columns are sealed in units of five columns each to prevent adsorption of contaminants from the environment, e. g. , laboratory air.