Headspace Sample Size

In addition to working with the partition coefficient (K), the phase ratio (β) and derivatization reactions, sensitivity can also be improved by simply increasing the size of the headspace sample that is withdrawn from the sample vial and transferred to the GC.

Increasing the sample size also means that the amount of time it takes to transfer the sample to the column will increase in proportion to the column volumetric flow rate.

Sample size can be increased only to the point that increases in peak width, caused by longer sample transfer times, will not affect chromatographic separations. Larger sample sizes and longer transfer times can be offset by using cryogenic cooling and sample refocusing at the head of the column.