Ethidium bromide

Ethidium bromide is an intercalating agent commonly used as a fluorescent tag (nucleic acid stain) in molecular biology laboratories for techniques such as agarose gel electrophoresis.

Guidelines (Following is our recommended protocol. This protocol only provides a guideline, and should be modified according to your specific needs).The preparation of agarose gel:1. Agarose gels are commonly used in concentrations of 0.5% to 2.5% depending on the size of bands needed to be separated.2. Mix the agarose powder with 1X TAE/TBE.3. Microwave for 1-3 min until the agarose is completely dissolved (Caution: not overboil).4. Make the solution cool down before solidification.5. Add ethidium bromide (EtBr) to a final concentration of approximately 0.2-0.5 μg/mL (Stocks are generally 10 mg/ml, and require 5 µL stock/100 mL gel).6. Ethidium bromide binds to the DNA and you could visualize the DNA under ultraviolet (UV) light.CAUTION: EtBr is a known mutagen. Please pay attention to strengthening protection.

[1]. P Stevenson, et al. Comparison of isometamidium chloride and homidium bromide as prophylactic drugs for trypanosomiasis in cattle at Nguruman, Kenya. Acta Trop. 1995 May;59(2):77-84. [2]. Sabnis, Ram Wasudeo (2010). Handbook of Biological Dyes and Stains: Synthesis and Industrial Application. Hoboken, NJ: Wiley. ISBN 978-0-470-40753-0.