Developing Inquiry-Based Labs Using Micro-Column Chromatography

Chromatography is a process by which mixtures can be separated or substances can be purified. Biological and chemical laboratories use many different types of chromatographic processes. For example, the pharmaceutical industry uses chromatographic techniques to purify drugs, medical labs use them to identify blood components such as cholesterol, crime labs use them to analyze evidence, and the oil industry uses them to purify components of oil including gasoline. Many lab manuals for high school biology courses include at least one lab designed to introduce students to the techniques of chromatography and associated biological concepts. The procedure most commonly selected is paper chromatography for the separation of plant pigments or different colored inks. These labs are easily performed in the typical high school setting but tend to take most of the class period to complete a single chromatograph. This article describes another technique that can be easily used, micro-column chromatography, which has the advantage of allowing many chromatographs to be completed during a single class period, thereby enabling many experiments to be conducted during that time. It also has the advantage of easily allowing for the different components of the sample to be collected for additional analysis. The micro-column chromatography activities described in this article allow for a number of concepts highlighted in the National Science Education Standards to be addressed. (Contains 3 figures and 1 table.)