TMB Substrates

Two-component TMB substrate for ELISA

This type of TMB solution is supplied as two parts. Part A is a H₂O₂ -containing solution and Part B TMB-containing one, in a separate bottle. Mix them at 1:1 ratio just before application.

Like one-component TMB solutions, this version of TMB solution is also designed for ELISA procedures. Mixed TMB solution of parts A & B produces a blue, soluble end product which can be read at 655 nm. The reaction can be stopped by using acid solution (e.g. 0.5 M H₂SO₄, 0.5 M HC_l, 1 M H₃PO₄) for converting the blue radical to the yellow diimine and being read at 450 nm, which has been reported to increase the sensitivity of the assay.

• Post termination stability: no change of OD within one hour, and <10% drop of OD within 24 hours after the addition of stopping solution

Stable for at least 12 months at room temperature, or 36 months at + 2-8 °C.