You said it was an emergency, here's your stair bar!
Oh, thanks!
I couldn't find a spoon.
What is a stir bar?
Well, it's this neat little thing that you can use to stir and mix liquids efficiently,
without causing a mess, if you do it properly. Why is this important?
Well, let me tell you about a super cool
study where scientists used a stir bar in their research.
This year, 2021, these scientists published a really cool paper about
how to detect landmines without seriously injuring anyone.
A land mine is a device that releases an explosion when someone steps on it.
The scientists used something called bioluminescence. This is when a set
of proteins produce something that glows.
Kind of like this glowstick.
Essentially, they created a way to detect landmines using bacteria.
Wow!
Before all of this, they had to send actual real-life people out
into those fields just to find those landmines.
Which is super dangerous.
Exploding landmines can seriously injure or kill people.
But how did they keep the glowing bacteria from absorbing into the ground?
Well, they inserted them into these gelatinous beads.
The bacteria continued to glow while in these beads,
and then the scientists could spray them over the fields from an airplane.
But in order to create these beads, the scientists had to use a stir bar.
Stir bar is magnetic. Inside the stir plate is another magnetic bar that spins.
Once you turn it on, it forces the stir bar to rotate.
It's a really useful way to stir solutions in the lab, without having to stir by hand.
We need to make sure we have the right size stir bar,
as they come in many different shapes and sizes.
As you can see, this glass is fairly large, so we want to use a stir bar that is also fairly large.
If we use a small stir bar, then the liquid won't stir very well.
You want to make sure you turn the machine on slowly because
if you turn it up all the way this will happen.
As you can see, this stir bar isn't having much of an effect mixing the liquid.
So, we'll want to use an appropriately sized bar.
Before turning the machine on, be sure to look at the labels on the buttons.
Sometimes there is an option to turn on the heat,
which for this experiment will prove to be very helpful.
Be careful if you are using a dangerous liquid, like a strong acid, because if you turn the stir
bar on too high it can splash. And, we don't want that to happen, especially if it's dangerous.
Oh, no! There's a mutation [physically melting pain ensues].
For this next step, if you're planning on adding a solute to the liquid,
add in the powder slowly while the stir bar is already spinning.
If you put in the powder before turning the device on it won't mix in well.
But, wait, how do you get this out without splashing yourself or making a mess?
Well, there's this neat little tool that you can use that has a magnetic
end to it that you can just stick into the liquid, and the stir bar will stick to it.
Clean the stir bar like you would any other piece of lab equipment. Now, your solution is
well mixed, and you can use it however you need. And, now that you know how to use the stir bar
correctly, maybe you can design a technique, just like these scientists, to help make a safer world.
Which is what science is all about.
One last thing, my name is Gloriana Charlton and I'm in the studio art major.
I never really thought I'd be interested in biology,
or any type of science, until I took Dr. Dyer's biology class.
Now, I want to integrate it into my career. Or you know, make it a hobby.
Making this video is one way I could do that.
Perhaps, if you're interested in biology or any type of science, you can do that as well!