Sodium azide is a preservative. It prevents bacteria from growing in the serum. We generally recommend that you add azide to the serum. DO NOT ADD AZIDE if you are planning to use the serum directly in cell culture. If you have azide and decide to remove it later, it can be easily removed by dialysis.
If you have a query regarding any of our products or services, please don't hesitate to submit your question below. A member of our support team will review and answer your question as quickly as possible.