Chemical Forums
Specialty Chemistry Forums => Biochemistry and Chemical Biology Forum => Topic started by: Borek on June 07, 2005, 04:49:40 AM
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What is their use in biochemical experiments?
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EDTA is used to titrate metals in Chemistry.
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What is EDTA used for in analytical chemistry I know :P However browsing the web in recipes for the solutions used in biochemistry experiments I often see buffers plus EDTA plus magnesium chloride. Buffer use is obvious, but what role plays MgCl2? And why is magnesium chelated with EDTA?
Same problem, additional question: sometimes succrose is used in high concentrations. Is it used just to obtain high viscosity, or something else?
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NOTE: not best answer - just from the top of my head - you should probably research more -
this is really simplified
Basics -
Mg ions can "activate" some enzymes
EDTA - chelates - picks up Mg ions
Assays - depends on what you are doing - isolating DNA, cutting it, ligating it. copying it, etc
so - you want to store DNA - it is usually done in a buffer with EDTA - one would not want enzymes to break down DNA
Now you want to "cut" the DNA - you might need Mg to "activate" the enzyme, so you have to added Mg - note it is usually more because it has to conpensate for the EDTA the DNA was stored in
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I am told that,
"So basically um, when you do a reaction Mg2+ is used as energy in an experiment, like PCR (polymerase chain reacction). So in order to stop the reaction, you add EDTA which complexes the Mg2+ so you don't have any energy to be used and stops the reaction"
Hope that helped. It's a quote from a 'personal communication'...i.e. I asked my friend Mike
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Mg2+ as a source of energy?
Are we talking about the same chemistry and the same periodic table? ;)
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Don't worry. I slapped Mike upside the head for that one.
I've never taken a biology course in my life. And henceforth promise to stay out of this section of the forum...no matter who my friends proclaim to be.
Cheers!