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    Hi all,

    I have no idea how to work this out...


    "The molar extinction coefficient of NADH is 6.22 x 103 M-1

    During an LDH assay using lactate and NAD+ as the substrates, the absorbance of the reaction mixture at 340nm increased from 0.05 to 0.6.

    What was the concentration of NADH at the end of the assay? "

    I assume this is a Beer-Lambert Law Question, but I don't know how to use the Beer Lambert Law to work this out. The Molar Extinction Coefficient is 6.22 x 103
    and the absorbance is now 0.6. I have no idea how to rearrange the Beer-Lambert Law to make C the subject.

    A = ebc
    0.6 = 6.22 x 103 . . .


    The only other thing I can think of doing is making a graph?
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    (Original post by AshEntropy)
    Hi all,

    I have no idea how to work this out...


    "The molar extinction coefficient of NADH is 6.22 x 103 M-1

    During an LDH assay using lactate and NAD+ as the substrates, the absorbance of the reaction mixture at 340nm increased from 0.05 to 0.6.

    What was the concentration of NADH at the end of the assay? "

    I assume this is a Beer-Lambert Law Question, but I don't know how to use the Beer Lambert Law to work this out. The Molar Extinction Coefficient is 6.22 x 103
    and the absorbance is now 0.6. I have no idea how to rearrange the Beer-Lambert Law to make C the subject.

    A = ebc
    0.6 = 6.22 x 103 . . .


    The only other thing I can think of doing is making a graph?
    Are you not given a path length? Once you have that, you have all parameters except c, which is what you're trying to calculate
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    (Original post by Asklepios)
    Are you not given a path length? Once you have that, you have all parameters except c, which is what you're trying to calculate
    The path length is 1cm

    I just don't know how to rearrange the formula to work out C
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    (Original post by AshEntropy)
    The path length is 1cm

    I just don't know how to rearrange the formula to work out C
     \displaystyle c = \frac{A}{\epsilon b}
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    (Original post by Asklepios)
     \displaystyle c = \frac{A}{\epsilon b}
    Oh thank you very much
 
 
 
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