Heike,
In the late sixties, early seventies, I used to use the original method (Bertalanffy  F.D., Ann New York Acad Sci, 84, 225-238, A New Method For Cytological Diagnosis of Pulmonary Cancer) for screening cytology slides fixed in alcohol for malignant cells, and thought that it worked quite well, as did my pathologist at the time.  The DNA of the nucleus being brilliant green, and the RNA cytoplasm of malignant cells brilliant orange.  However, I have never met a cytotechnologist who liked the method, so, when I was forced to hire one because of work load, she quickly relegated this technique to the garbage bin of history.  I don't know of anyone who is currently using the technique.  However, as we found it very usefull at the time, I worked out a method for using it on parafin sections, that gives very similar results to the alcohol fixed smears.

1. Bring parafin sections to water in usual manner.
2. Stain sections in Acridine Orange stain for 30 min.
3. Rinse sections briefly in 0.5% acetic acid in 100% alcohol.
4. Rinse sections in two additional changes of 100% alcohol.
5. Rinse sections in two changes of xylene.
6. Mount sections in Fluoromount.

Results
Cell DNA. --- brilliant green
Cell RNA. --- brilliant orange
Most gram positive micro organisms --- brilliant orange
Most gram negative micro organisms (including helicobacter) --- green to pale orange

Acridine Orange Stain

Acridine orange ----- 0.05 gm
Dist water --------------- 500.0 ml
Acetic acid ------------- 5.0 ml
(note, some acridine orange dyes work better than others)

Kerry Beebe ART
Kelowna Gen Hospital
Kelowna B.C.  Canada
bbracing@silk.net