6 replies to this topic

[Bassaml7]

Hi,

I am out of Ethanol molecular biology grade . But I have HPLC grade Ethanol. Can I use it for DNA extraction instead ?

Also in general , do you think that it's safe to use analytical grade reagents ( not Molecular biology grade ) for DNA extraction ? certainly this doesn't work for PCR reaction assembly . I just mean DNA extraction reagents e.g. Phenol , Chloroform , Ethanol , Sodium Acetate ..etc . I suppose this should not be a problem as long as DNA is finally dissolved and stored in TE buffer (Molecular Biology grade) provided the reagents aren't contaminated with nucleic acids.

Perhaps what I am thinking is not recommended for routine use But at least maybe one can use the availabe analytical grade reagent till the new molecular biology reagents supply arrive at the lab .

Have you every tried that yourself anyway ?

Thank you

Edited by Bassaml7, 10 October 2009 - 05:40 AM.

[Vini]

Bassaml7, on Oct 10 2009, 07:06 PM, said:

Hi,

I am out of Ethanol molecular biology grade . But I have HPLC grade Ethanol. Can I use it for DNA extraction instead ?

Also in general , do you think that it's safe to use analytical grade reagents ( not Molecular biology grade ) for DNA extraction ? certainly this doesn't work for PCR reaction assembly . I just mean DNA extraction reagents e.g. Phenol , Chloroform , Ethanol , Sodium Acetate ..etc . I suppose this should not be a problem as long as DNA is finally dissolved and stored in TE buffer (Molecular Biology grade) provided the reagents aren't contaminated with nucleic acids.

Perhaps what I am thinking is not recommended for routine use But at least maybe one can use the availabe analytical grade reagent till the new molecular biology reagents supply arrive at the lab .

Have you every tried that yourself anyway ?

Thank you

yeah, I had the same problem once...had to extract genomic dna and no mol. bio. grade stuffs were there in d lab....i went ahead with the analytical grade (had already spent 3 days in culturing!) and it works....quality and quantity both good....So, I think its safe.....but, dont make it a practice  

[Bassaml7]

DRN, on Oct 10 2009, 10:29 PM, said:

Bassaml7, on Oct 10 2009, 07:06 PM, said:

Hi,

I am out of Ethanol molecular biology grade . But I have HPLC grade Ethanol. Can I use it for DNA extraction instead ?

Also in general , do you think that it's safe to use analytical grade reagents ( not Molecular biology grade ) for DNA extraction ? certainly this doesn't work for PCR reaction assembly . I just mean DNA extraction reagents e.g. Phenol , Chloroform , Ethanol , Sodium Acetate ..etc . I suppose this should not be a problem as long as DNA is finally dissolved and stored in TE buffer (Molecular Biology grade) provided the reagents aren't contaminated with nucleic acids.

Perhaps what I am thinking is not recommended for routine use But at least maybe one can use the availabe analytical grade reagent till the new molecular biology reagents supply arrive at the lab .

Have you every tried that yourself anyway ?

Thank you

yeah, I had the same problem once...had to extract genomic dna and no mol. bio. grade stuffs were there in d lab....i went ahead with the analytical grade (had already spent 3 days in culturing!) and it works....quality and quantity both good....So, I think its safe.....but, dont make it a practice  

Thank you very much

[HomeBrew]

HPLC grade reagents are actually ultra pure (and expensive) -- they're made more pure so they won't introduce stray peaks from contaminants on the HPLC trace.  For stuff like DNA extractions, lower grade reagents are fine...

[Bassaml7]

HomeBrew, on Oct 11 2009, 04:19 AM, said:

HPLC grade reagents are actually ultra pure (and expensive) -- they're made more pure so they won't introduce stray peaks from contaminants on the HPLC trace.  For stuff like DNA extractions, lower grade reagents are fine...

Do you mean lower grade than Molecular biology grade ? or HPLC grade ? I thought Molecular biology grade is more expensive than HPLC . perhaps HPLC is chemically more pure than Molecular biology ...whereas Molecular biology grade is "biologically" more pure than HPLC grade.

[HomeBrew]

HPLC grade chemicals are manufactured for a particular application (HPLC) and are typically glass distilled, submicron filtered, and undergo rigorous specification testing.  Molecular biology grade chemicals are manufactured for general use in molecular biology procedures, and do not undergo such rigorous purification and testing.

For routine lab use, there is little need to use ultra pure reagents.

[Bassaml7]

HomeBrew, on Oct 11 2009, 08:06 AM, said:

HPLC grade chemicals are manufactured for a particular application (HPLC) and are typically glass distilled, submicron filtered, and undergo rigorous specification testing.  Molecular biology grade chemicals are manufactured for general use in molecular biology procedures, and do not undergo such rigorous purification and testing
For routine lab use, there is little need to use ultra pure reagents.

Alright , thanks for the answer . I have another question : what are the main differences between Molecular biology Grade and Analytical Grade ? Now what I know is that Molecular biology grade reagents are Nuclease ( RNAse and DNAse ) free and also Protease free . But in fact I doubt that any analytical grade reagent would be contaminated with significant amounts of Nuclease or Protease anyway especially reagents like HCL for example . Nucleic acids and Nucleases are not stable in such a medium in the first instance. So why do they even bother manufacturing that .

And another question , Analytical grade reagents are cheaper than Molecular biology grade reagents . Then why isn't it common to just convert an analytical grade reagent to a molecular biology grade reagent simply through Autoclaving and/or Filtering in our laboratories ?. I mean every one has an autoclave and Proper filtering tools . And It doesn't take too much time.