sentence: Packed columns are created of fused silica or stainless steel.
sentences_before: The main type of columns used in gas chromatography is a capillary column.
sentences_after: To increase separation of a gas sample columns must be created of a large length and are coiled to fit inside of the oven. WCOT are capillary tubes with a thin layer of stationary phase, and in SCOT, the tube is lined with a thin film of support material. As the sample moves through the column the individual parts of the sample become contained with the material inside of the column and are then released. This action allows for a sample to become separated.
concept_name: packed column
headings: Gas chromatography Instrument Column
categories: Laboratory techniques