Open AccessImaging of immunolabeled membrane receptors in uncoated sem specimens
Author(s) -
Heinzmann U.,
Reininger A.,
Autrata R.,
Höfler H.
Publication year - 1994
Publication title -
scanning
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.359
H-Index - 47
eISSN - 1932-8745
pISSN - 0161-0457
DOI - 10.1002/sca.4950160409
Subject(s) - immunogold labelling , materials science , optics , biophysics , electron microscope , chemistry , analytical chemistry (journal) , biology , physics , chromatography
Epidermal growth factor receptors (EGFR) were labeled with 10 nm immunogold and examined on uncoated specimens of A431 human epidermoid carcinoma cells. A field emission gun and a high‐sensitivity YAG ring detector were used to demonstrate the affinity labeling simultaneously in the secondary‐electron (SE) and backscattered‐electron (BSE) modes with a low accelerating voltage (V o ). At V o =2kV, the SE and BSE signals were too weak to identify all markers, while at V o =3–7 kV labeling was observed unambiguously in both the SE and BSE modes with smaller and higher working distances. Increasing the V o to above 7 kV sometimes provokes instability of the specimens. A V o of ⩾ 10 kV produces charging artifacts in the SE image, but permits a BSE image of the gold markers providing additional topographic information. In conclusion, immunogold labeling can be used with good results for uncoated specimens.