viewing live yeast cells

[Ocean Breeze]

Wondering if theres anything that we can use to stain live yeast cells for easier viewing under microscope. Alternately, the medium that they are in could be stained/coloured.

Food colouring?

[ellice]

Methylene Blue comes to mind.

[ri]

Hello there,
If you have these attachments, you can optically induce contrast into living and colourless material under the microscope.
If the teacher uses a video microscope that displays to the classroom via a monitor-
1. Phase contrast technique. You need to have the kit which is special phase contrast lenses and condenser to replace the ones on your microscope.
2. Darkfield, again this technique uses a special condenser only that fits into your condenser holder.
As far as the kids microscopes go- if you can close down the condenser iris, this also indroduces contrast when viewing the specimen.
Hope this helps,
~Robyn

[Trudy]

Haven't tried this but Congo Red can also be used for staining yeast. 1g congo red in 10ml ethanol, Make up to 100mls with distilled water - make fresh. Just in case you haven't got recipe for the methylene blue stain. Stock Solution = 1.5g methylene blue in 100ml 95% ethanol. Dilute stock 1:10 with distilled water. The method also says that to differentiate between live and dead cells you mix equal volumes of dilute yeast suspension and methylene solution. Make a wet prep. Dead cells absorb the dye and look blue, live cells appear translucent. ( The Laboratory pg 130). Hope this is helpful

Trudy