TBE (Tris-Borate-EDTA) 5X buffer concentrate solution consists of 0.45M Tris, 0.45M Borate and 0.01M EDTA adjusted to pH 8.0 (± 0.2). Dilute to 1X using sterile water for use as electrophoresis buffer. Dilution to 0.5X concentration also has been shown to achieve comparable electrophoretic separation. At Gene Link we use 0.5X concentration and recommend it.
Concentrated TBE buffers are prone to precipitation. They are shown to still retain buffering capacity and can be put to limited use instead of discarding.