Ham's F-12K (Kaighn's) Medium is a modification of Ham's F-12 Nutrient Mixture. Ham's F-12K (Kaighn's) Medium was developed for primary human hepatocytes, as well as for some rat and chicken liver cells in a reduced serum environment.

This F-12K (Kaighn's) Medium is manufactured as follows:

The complete formulation is available.

Using Ham's F-12K
Ham's F-12K (Kaighn's) Medium contains many components not found in traditional basal media, such as putrescine, thymidine, hypoxanthine, zinc, and higher levels of all amino acids and sodium pyruvate. These additions allow the medium to be supplemented with very low levels of serum or defined components, for some cell types. Ham's F-12K (Kaighn's) Medium contains no proteins or growth factors, and is therefore often supplemented with growth factors and Fetal Bovine Serum (FBS). The FBS concentration must be optimized for each cell line. Ham's F-12K (Kaighn's) Medium uses a sodium bicarbonate buffer system (2.5 g/L), and therefore requires a 5–10% CO₂ environment to maintain physiological pH.