2X sample buffer vs. 6X - (Jul/20/2009 )
What is the difference between 2X vs. 6X sample buffer and how do you know how much you should add of each into your samples before loading your gel? Thanks!
THe difference just lies in the concentration.
2X means you need to do a 2X dilution. So say.. you wanna load 10ul, that will be 10ul/2 = 5ul of your sample buffer to load to 5ul of your samples.
6X means a 6X dilution is required, so say... for 10ul, it will be 10ul/6 = 1.7ul of your sample buffer to load to 8.3ul of your samples.
so for example, if I have a stock that has a concentration of 10 micrograms/microliter and I want a concentration per lane of 100 microgram/microliter...I would need 10 microliters to get this concentration. How much 6X would I need to add to this?
Add 2 ul to 10 ul. It's close enough -- you need not worry that your loading dye is not precisely 1x, just that it is sufficient to serve its purpose -- to weigh down the DNA so it won't float out, and give you an observable marker for the run.
The difference is 4x 
.
It means how concentrated it is, ie how many times (hence the X) working concentration (or 1X) it is.
So, for example, your 2X buffer is 2 times more concentrated than a working concentration of the buffer.
PS.