Alyson Tobin wrote:
>> Does anyone know of a good, simple, stain for lipids in plant tissue? Our
> students are looking at seed storage reserves and comparing oily and
> starchy seeds. In the past I have got them to cut seeds in half and add
> Sudan III to stain for lipids. It is very difficult for them to see the
> staining as Sudan is red and a positive test is the formation of a dark red
> stain on the tissue- hard to see against a red background of dye. Any
> suggestions?
>> Alyson Tobin
>> Dr A.K. Tobin
> Plant Science Laboratory
> Sir Harold Mitchell Building
> University of St Andrews
> St Andrews
> KY16 9TH
> UK We used to do a similar lab in an intro course. We (the lab tech) sectioned
slices of brazil nut (50 um thick)and floated them in water contained in a petri dish.
The sections were stained on a microscope slide using a saturated solution of SUDAN IV
in absolute ethanol (filtered). Excess stain was rinsed off of the tissue with water
and lighlty blotted with a kimwipe. A wet mount was then made and observed under a
compound scope. As I recall this seemed to yield good results.
Hope this helps,
Bob in Chico
P.S. A simple microtome can be made using a large Bolt and nut. The specimen is
placed in a well created when the nut is screwed almost to the point of being off of
the bolt. This well containing the specimen is filled with molten wax and allowed to
cool. By tightening the nut onto the bolt the wax/specimen is forced up beyond the
end of the nut slightly and a razor blade can be "sliced" across the top of the nut
yielding an amazingly good section. The wax usually just falls off of the section so
it does not interfere in any staining procedures.
Cheers
