13
Protocol
Component RPN1604/5 RPN1606/7
Labelling 10 µl
buffer
Unlabelled 4 µl of each –
dNTPs omitting
those to be
used as
label
Reaction 5 µl –
buffer
Radiolabelled
(dNTP) 5 µl 5 µl (dCTP)
Enzyme 2 µl 2 µl
6. Mix gently by pipetting up
and down and cap the tube.
Spin for a few seconds in a
microcentrifuge to bring the
contents to the bottom of the
tube.
7. Incubate at 37°C for 10
minutes
Notes
6. Avoid vigorous mixing of the
reaction mixture as this can
cause severe loss of enzyme
activity.
7. Purified DNA can be labelled
to high specific activity in
10 minutes at 37°C but, if
desired, can be labelled for
up to 1 hour at this
temperature. When labelling
DNA in low melting point
agarose, longer incubation
of 15–30 minutes at 37°C are
required for optimum
labelling. Longer incubation