00:09
So geometric dilution basically is measured to make sure that a small amount of a potent drug diluted with large amount of diluent, which is the solvent in here.
00:22
And it's a step -by -step dilution.
00:29
Let me give you an example of geometric dilution.
00:32
Say you start out with a very potent stock, say one millimeter.
00:39
Now in geometric dilution, you can add that into a tube with, let's say, 9 mill liter of diluent, large amount.
00:51
So you end up having 10 mil in total.
00:55
So from there, you can see the first step is called 1 to 10 dilution.
00:58
So you have a small amount of stock, initial stock, which has a very high concentration.
01:05
Then you dilute it with a large amount of diluent in this case, the water here.
01:11
And you increase the volume and the concentration drops ten times.
01:18
And then you follow the second step.
01:22
And then you take one millimeter out from the first tube, and then you put them into second tube, which it has the same amount of diluent.
01:31
So you can see that, again, it's a 1 to 10 dilution compared to the first one.
01:36
But compared to the stock, it's actually combined, so it's a 1 to 100 dilution.
01:41
Now if you keep going, you can take another 1 milfought tube number two and add into 9 militer of diluent, and then you'll have a 1 to 10 dilution compared to tube number two, but compared to the initial stock, it's gonna be 1 to the third power dilution.
01:58
So you can see, this is called the geometric dilution that you start out with the stock with a very small volume and then you do a step -by -step, multiple process that you're able to do a huge quality, of dilution.
02:10
So you can see we repeat three different steps and then you already diluted to a thousand times.
02:16
So this is what we call a geometric dilution.
02:19
Now the second question, when is geometric dilution applied in preparation of powder? so in this case, a geometric dilution typically apply in the preparation powder when you have a potent drug because you have a very potent, there's a highly concentrated drug to begin with.
02:47
You only need very small amount of active ingredient.
02:50
And they need to be evenly distributed through a large amount of dilute.
02:55
So this is when we use the geometric dilution...