DESCRIPTION
TMB BlueSTOP is specifically designed for use with SureBlue™ 1-
Component, SureBlue Reserve™ 1-Component, and TMB 2-
Component （see RELATED PRODUCTS） substrates to stop color
development in ELISA. Unlike traditional TMB stop solutions,
TMB BlueSTOP allows the chromophore to remain blue, instead of
turning yellow. The stopped solution results in a stable blue reaction
product.

FORM/STORAGE/STABILITY
Catalog Number 50-85-30 consists of 4 X 100 mL bottles.
Catalog Number 50-85-41 consists of 1 X 1000 mL bottle.
Store at 4ºC. Stable for a minimum of 24 months from the date of
manufacture.

Volume:
TMB BlueSTOP solution should be added to each well in an
equivalent volume to the TMB substrate volume （usually 100 μL）.

Stopping TMB:
The addition of TMB BlueSTOP results in a stable blue reaction
product. Absorbance values will not change significantly as a result
of stopping with TMB BlueSTOP. This allows the user to monitor
the substrate reaction and stop the reaction at the desired absorbance
value. Stopped TMB should be read at a wavelength between 600
and 650 nm. The stopped plates should be read within two hours
after stopping.
When to Stop Substrate Reaction
A stop solution has greatest utility in ELISA assays when the user is
working with several microwell plates at one time and development
time with the substrate is critical. Microwell plates can then be read
without fear of over-development.

Quantitative ELISA:
If the stop solution is being used in a quantitative ELISA assay, the
period of incubation with the substrate will depend on several factors,

including: desired range of analyte concentration, required
sensitivity and reader capabilities.
Qualitative ELISA:
If the stop solution is being used in a qualitative ELISA assay, stop
solution can be added at the time that visual discrimination between
positive and negative is possible. An example would be the
screening of murine monoclonal antibody hybridomas.
NOTE: TMB BlueSTOP has been specifically designed to work
with KPL TMB Substrates. Other TMB substrates may appear green
when stopped, due to a difference in pH. KPL makes no claims
regarding how TMB BlueSTOP will work with TMB substrates other
than those produced by KPL. Conjugate concentrations should not
be higher than 1 μg/mL, as excess conjugate may result in a reaction
that is difficult to control.