Outreach is a really important part of Science Research, some would argue (and I would agree) that it is an obligation of Scientists to talk about what they do and inform and inspire the general public.
When outreaching about Cell Biology and specifically, Microscopy, it’s great to be able to show people their own cells on a microscope. To figure out how best to do this in a quick, safe and cheap way, I had a play with some live-cell staining of buccal (cheek) epithelial cells.
You will need:
- microscope slides (I used 76×26×1 mm slides from VWR)
- coverslips (16mm diameter circular coverglass thickness #1, from VWR)
- A nuclear marker that works in live cells. I used DAPI, because we had some in the fridge and I know it’s moderately cell permeant
- Phosphate buffered saline (PBS)
- Cotton buds
None of this is particularly expensive and should be kicking around any reputable Cell Biology lab. Here’s what you do:
- Make up a 1:100 solution of DAPI in PBS by diluting the 5mg/mL stock solution
- Swallow a couple of times to dry out your mouth a bit. Take a cotton bud and, applying gentle pressure to the outside of your cheek, rub the bud onto the inside of your cheek backwards and forwards 3-4 times.
- Rub the swab onto the slide, try to stick to a relatively small area, maybe 0.5cm²
- Add 5-10uL (depending on your coverslip size) of the diluted DAPI solution onto the slide then carefully place a coverslip on top
The surface tension should keep the coverslip held onto the slide, but use caution as you transfer the slide to a microscope.
Use filter sets and a light source for your dye. DAPI has a maximal excitation and emission of 358nm and 461nm respectively when bound to DNA. Take some pretty pictures! Be warned that the number of cell that you get from a cheek swab is relatively low, so you will need someone with experience on the microscope to be able to find them.