GC045 Capillary columns

Capillary columns are columns that are not filled with packing material. Instead, they are internally covered by a thin film of a liquid phase. They are formally called “wall-coated open tubular” or open tubular (WCOT or OT columns). Their resistance to flow is very low, and long lengths are possible, up to 100m, which also permits efficient separation of very complex sample mixtures. Fused silica columns are the more inert.

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