Glass Spreader
What are they and why do we use them? What types are there?
A glass spreader is a glass rod that has been bent into a ‘hockey stick’ shape by heating in a bunsen. It is used in Sterile Technique for the transfer of a liquid culture to a solid medium.
You will need a glass rod, tongs and a bunsen burner to make one. Simply hold the glass rod (using the tongs) in the hot bunsen flame until you feel it start to bend. Slowly bend the glass rod into the desired shape. A right angle is my favourite, but some scientists prefer to make a more triangular shape.
You will also want a small glass jar with a diameter greater than the short end of your glass rod. This will contain ethanol for setting the glass rod aflame.
You will also need a lid for the glass jar, just in case you drop flaming ethanol into it…
When do you use?
Sterile transfer of Liquids > Solid during Sterile Technique.
How do you use?
Once you’ve inoculated a plate, dip the glass rod into a jar of ethanol. Keep the lid handy in case the jar catches fire.
Pass the ethanol soaked glass rod through the flame. It will catch fire and burn out within 2-3 seconds.
You now have a sterile glass rod. Pass it gently over the liquid you added to the plate, turning the plate as you go. Stop after 10 seconds, or when it starts to feel a bit sticky. Replace the lid and parafilm the plate.