Chemisch drogen: biologisch monsterpreparaat voor het scannen van elektronenmicroscopie (SEM)

- To begin, start by dehydrating and drying a fixed sample to reduce sample distortion caused by the removal of gases and liquid water at the reduced operating pressure of conventional scanning electron microscopes, SEMs.

To dehydrate the sample, wash it with increasing concentrations of ethanol in water until 100% ethanol is reached. Then repeat this process with a chemical drying agent in ethanol until the sample is washed with pure drying agent. Transfer the sample and drying agent to an evaporating dish. Cover it with minimal additional drying agent and let it dry in a fume hood overnight.

Next, mount the prepared sample on the top of a microscope stub using carbon adhesive tape. Finally, apply silver paint to the edges of the stub, then from the edge of the stub to each of the samples, to reduce the buildup of excess electrons, which could result in undesirable image artifacts.

In this experiment, fruit flies, Drosophila melanogaster, are prepared for SEM analysis using the drying agent HMDS.

- To prepare Drosophila melanogaster, immerse anesthetized flies in 1 milliliter of fixitive for 2 hours at 4 degrees Celsius, making sure they are completely submerged.

Use a glass pipet