Pre-embedding immuno
incubation procedure
using Ultra Small Immunogold Reagents
(subnanometer gold particles)
A rocking table is recommended for
facilitated penetration and reagent exchange. Compared to post-embedding
procedures longer incubation and wash steps are required.
1. To
inactivate residual aldehyde groups present after aldehyde fixation specimens
are incubated with 0.1% NaBH4 in PBS buffer for 15-30 minutes.
2. Wash
with PBS for 3x10 minutes
3. When working with tissue slices or compact
material a pre-treatment with detergent is required to provide acces to
internal antigens. In practice: permeabilize with 0.05% Triton-X-100 in PBS for
30 min.
4. Transfer the specimens into matching AURION BLOCKING SOLUTION for 30
minutes up to 1 hour.
5. The specimens are washed with INCUBATION SOLUTION for 2
x 10 minutes.
6. Incubate with a dilution of specific primary antibody,
preferably affinity-purified, 1-5 µg/ml, or a high dilution of a high
titre antiserum, made up in INCUBATION SOLUTION for at least 1 hour. Antibody
concentration and incubation time may have to be adapted according to the
specific characteristics of the primary antibody. Longer incubation times are
usually required to warrant full penetration to antigens. In those cases the
procedure should be carried out at 4°C .
7. The specimens are washed
with INCUBATION SOLUTION for 6 x 10 minutes.
For Streptavidin reagents in
a three step labeling set-up only:
Incubate with the biotinylated secondary
antibody according to step 5, rinse according to step 6 and proceed with step
7.
8. The specimens are transferred into aliquots of the appropriate
gold conjugate reagent, diluted 1/50-1/200 in INCUBATION SOLUTION for 30
minutes to 2 hours. It is recommended to test a series of dilutions and
incubation times for each new localisation study. Again, longer incubation
times are usually required to warrant full penetration to antigens. In those
cases the procedure should be carried out at 4°C .
9. The specimens
are washed with INCUBATION SOLUTION for 6 x 10 minutes.
10. Wash twice
with PBS for 10 minutes each, postfix in 2% glutaraldehyde in PBS for 15
minutes and finally wash with distilled water for 4x10 minutes.
11.
Proceed with Silver Enhancement using AURION
R-Gent SE-EM as described in the adjacent section.
RECOMMENDED FOR EM