1. Dot blot can be used to estimate protein concentration in crude
or partially purified samples.
2. Cut nitrocellulose membrane to the appropriate size to
fit in the dot-blot apparatus. Wet the membrane by immersing it in
deionized water. For PVDF membrane pre-wet with methanol for seconds
and soak in deionized water. Add sample and standard diluted in
100 m l of PBS/0.05% Tween 20 to each well.
Draw the liquid through the membrane by applying suction pump.
2a. Alternatively cut nitrocellulose membrane (not PVDV) to the
Draw grids with a pencil. Spot 1 m l of the
sample and standard in the center of the grid. Let the membrane dry.
You may make serial dilution of the sample and standard.
3. Proceed to Western.