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Specialty Chemistry Forums => Biochemistry and Chemical Biology Forum => Topic started by: socomplicated on September 02, 2004, 05:48:18 PM

Title: Conc. of bio solns
Post by: socomplicated on September 02, 2004, 05:48:18 PM
here is a part of the protocol we did:

a)spin down the chloroplast solution and decant the supernatant. add 4ml water to the pellet.

b) add 10ul proteinase K ( concentration= 20mg/ml) to get a final concentration of 50ug/ml.

-> how do they get 10ul? which formula do they use? i don't think that they use the dilution formula (C1 XV1= C2 X V2) since we don't know the total volume of the solution. it can't be 4ml, because when we add proteinase K the volume of the solution will increase.


c) then add slowly 0.25ml 10% or 0.125ml 20% SDS to get a final concentration of 0.5% SDS.

-> again, how do they come to 0.25ml 10% or 0.125ml 20% SDS to get a final concentration of 0.5% SDS?


i am very stucked, please *delete me*
Title: Re:how come, how come???!!!
Post by: Mitch on September 02, 2004, 07:11:25 PM
c.) When it says % SDS it most likely means volume/volume. For the 10% case add 0.025ml SDS and 0.135ml water. Or scale it up accordingly.
Title: Re:Conc. of bio solns
Post by: savoy7 on February 03, 2005, 03:02:58 AM
SDS can be purchased as a solid - if it is - usually % is grams/ml
so grams of sds/ml total solution