Monday, February 22, 2010

Science Project: Microscope Staining Cells

Since many cells are almost transparent under a microscope, it is sometimes necessary to stain them in order to view components of the cells. There are quite a few different types of stains available. You can view a list of the most common microscope stains here.

While many stains are advanced, below is a basic staining activity that you can try at home. There are several types of stains you can use at home including: food coloring, iodine, malachite green (ick fish cure), and methylene blue. You can purchase food coloring at a grocery store, iodine at a pharmacy, and the malachite green and methylene blue can be purchased at an aquarium store.

Certain stains will color different parts of a cell. Experiment with your own to see which part of the cell the different stains attach to. Make sure you have adult supervision - stains can be messy and not only will they color your specimen, but also your hands, the table, carpet, etc. Make sure you put plenty of paper underneath your work area and have some spare towels handy to wipe up any spills.

Science Project: Create a stained prepared slide of your cheek cells and compare this with an unstained prepared slide.

You will need the following items:
Gently scrape the inside of your cheek with the toothpick or Q-Tip to get some cheek cells. You do not need to press hard. Prepare two identical wet-mount slides by placing the cheek cells and one drop of water on each of the blank microscope slides and covering them with cover slips. 

Set one of the prepared slides aside and with the other prepared slide apply the staining material. The image below shows how you can pull the stain into the slide. Place your drop of stain on one side of the cover slip and use a paper towel to pull the liquid out of the other side of the cover slip. When the liquid is pulled out from the left the stain will be pulled under the cover slip from the right.

Take a look at each slide under the microscope. Do you notice differences in the details you can view in the cheek cells? Try the same activity above, but this time try a different type of stain. Make sure you document your science project and draw images of your cheek cells. You may want to share your findings with your classmates!