The introduction of liquid samples into a capillary gas chromatography (GC) column is by no means trivial. Representative amounts need to be introduced with no changes in the sample composition due to adsorption, (thermal) degradation, or discrimination. The injection bandwidth should be sufficiently narrow so as not to adversely affect the separation power of the system. Yet sufficient sample should be introduced to meet ever more stringent detection requirements, such as in environmental and safety research. Of course, the system should be reliable and rugged, versatile and flexible, while at the same time easy to operate. Armed with the right understanding of the principles of the basic techniques of split-, splitless- and on-column injection, the analyst can meet these requirements. With the right understanding of large-volume injection methods, the analyst is also ready for the challenges of further reduced detection limits. The principles of standard-volume and large-volume injection methods for liquid injections in GC will be discussed and illustrated with examples from various application fields.

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