KnockOut™ Serum Replacement

Gibco™ KnockOut™ Serum Replacement (KnockOut™ SR) is a more defined, FBS-free medium supplement that supports the growth of pluripotent stem cells (PSCs) cultured on fibroblast feeder cells. Designed to replace fetal bovine serum (FBS) in existing protocols, this serum replacement has been trusted by many for almost 20 years. Providing the documents required for regulatory review, KnockOut SR reduces your burden in qualifying reagents when transitioning from research applications to clinical applications. If you are interested in only basic research applications, see the Research Use Only version of this product to ensure that you receive the benefits and pricing that fit your needs.

With KnockOut Serum Replacement, you can:

Culture feeder-dependent PSCs with confidence

Rely on the improved performance of a qualified, FBS-free formulation

Enjoy the peace of mind of having a more stable price and supply compared to FBS

Culture PSCs with confidence
KnockOut SR has been cited in more than 2000 publications. It has been shown to support feeder-dependent culture of embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs). It has also been shown to support reprogramming, embryoid body (EB) formation, in vitro differentiation, cryopreservation, ESC derivation, and many other applications.

Rely on improved performance
KnockOut SR has more a defined formulation compared to FBS, which contains many undefined and variable components. Unlike most FBS products, each lot is tested for its ability to support PSCs. Because of this, culturing PSCs with KnockOut SR leads to less differentiation and more compact colony morphology compared to FBS.

Enjoy the peace of mind of having stable price and supply
KnockOut SR is not affected by the limited supply and fluctuating prices often seen with FBS. This makes it easier to plan your budget and buy what you need, especially since it is more affordable than most FBS products.



This reagent is classified as a medical device in several countries. If it is not regulated as a medical device in a specific region, it should be used for laboratory use only.