Ham’s F-12K (Kaighn’s modification of Ham’s F-12) is a nutrient-rich medium designed for demanding cell lines and low-serum culture. It builds on Richard Ham’s original F-12 formulation, created for the serum-free clonal growth of Chinese hamster ovary (CHO) cells, and adjusts several components for stronger support. This guide explains what F-12K is, how it relates to F-12, what it contains, and which cells it suits.
Key Facts
- Type: Nutrient-rich medium (Kaighn’s mod of Ham’s F-12)
- Best for: CHO cells and specialized lines
- Notable: Adds putrescine, hypoxanthine, thymidine, zinc
- Buffering: Bicarbonate (use a CO2 incubator)
What is Ham’s F-12K?
Ham’s F-12 is a richly supplemented basal medium first developed by Richard Ham for growing CHO cells with little or no serum. Kaighn’s modification, known as F-12K, raises the concentration of several amino acids and other components, producing a more nutrient-dense medium that supports a broader set of demanding cells. Like other basal media, F-12K supplies salts, amino acids, vitamins, and glucose, and it is completed with serum and glutamine before use.
What is in Ham’s F-12K?
F-12K is notable for its wide range of components, including:
- A broad set of amino acids at raised concentrations compared with standard F-12
- A rich vitamin profile and added trace elements
- Putrescine, hypoxanthine, thymidine, and zinc, components not found in older media
- Glucose and a bicarbonate buffer with phenol red, so it needs a CO2 incubator
What is Ham’s F-12K used for?
F-12K suits cells that benefit from a rich, well-rounded environment, including:
- CHO cells and other lines descended from Ham’s original F-12 work
- Certain endothelial and specialized cell lines
- Cultures moving toward reduced-serum conditions
Ham’s F-12 is also widely blended 1:1 with DMEM to make DMEM/F-12, a popular medium that pairs DMEM’s richness with F-12’s broad component list.
How to supplement and use Ham’s F-12K
Before use, F-12K is completed with serum (commonly 10% FBS) and L-glutamine or a stable glutamine dipeptide. Keep it in a CO2 incubator, store it refrigerated and protected from light, warm it gently before use, and keep the same lot across an experiment for consistency.
Order from PurMa Biologics
PurMa Biologics manufactures Ham’s F-12K in the USA, with or without L-glutamine, each lot backed by a Certificate of Analysis. See our Ham’s F-12K or browse the full range of cell culture media. You can also read our related guide on DMEM. Questions or need a quote? Contact our team.
