View source for Bromophenol blue

[[Image:Agarose gel dyes.jpg|right|200px]]

'''Bromophenol blue''' (BPB) is most commonly used as an [[agarose gel electrophoresis]] size marker. In a 1% gel it runs at around 500bp but the higher % of the gel the lower it will run. Despite its larger molecular weight of 670g/mol it runs faster than [[Xylene cyanol]] (539g/mol) because of its larger negative charge (hydroxyl groups).

Bromophenol blue is also a pH indicator which is yellow below pH=3 and blue-purple at more basic pH.

* 1000bp at 0.7% agarose
* 500bp at 1%
* 150bp at 2%
* 50bp at 3% 

== See also ==
* [[agarose gel loading buffer]]
* [[agarose gel electrophoresis]]
* [[Xylene cyanol]] - slower than BPB
* [[Cresol Red]] - slower than BPB

== External links ==
* [http://en.wikipedia.org/wiki/Bromophenol_blue Bromophenol blue at the Wikipedia]

[[Category:Material]] [[Category:Dye]] [[Category:Agarose gel electrophoresis]]