Ethanol Preparation BIO 498/698

Materials for EtOH prep A: Sand for sand prep (white or black) B: Gel for gel prep C: 70% ethanol wash bottle D: Petri dishes of various sizes with/without sand E: Pin and hard forceps

Sand vs Gel techniques When to use Sand : – Type specimens (gel leaves residue) – Needing to position specimens easily/quickly Gel: – Plain background – When you don’t want to bury (hide) any features of the specimen

Sand Technique When to use… White sand – Somewhat dark specimens – Creates less shadow Black sand – Lighter specimens White sand is generally used the most.

Sand Technique: How-to Pour sand into Petri dish Have enough sand to bury part of specimen and enough to completely cover top of specimen with EtOH

Sand Technique Fill Petri dish with EtOH. Have just enough EtOH to cover sand.

Sand Technique Make sure Petri dish is appropriate size for specimen being imaged. Take specimen out of container and put in Petri dish on top of sand.

Sand Technique Position specimen to desired orientation.

Sand Technique Add enough Ethanol to just cover specimen completely (a few mm). To prevent evaporation, you can temporarily cover dish. Note: If you have too much ethanol covering specimen, there may be distortion in your images.

Gel Technique: How-To Using hooked pin, get a glob of gel. Dab gel onto bottom of dish in the center.

Gel Technique Only use just enough gel to keep specimen in place. Position specimen on top of gel.

Gel Technique Fill dish with Ethanol to just cover specimen. Specimen is now ready to image!