Extinction Coefficient of Hydrogen Peroxide

[Shaun D. Black]

We determined the extinction coefficient of hydrogen peroxide at a couple of
wavelengths, and have found that these behave pretty well, though I can't
comment on the exact accuracy of them.  We used a molecular weight for H2O2
of 34.02 g/mol and a density of 1.463 g/ml (Merck Index).  Absorbance 
measurements were made on solutions of H2O2 diluted from a fresh 30% stock 
(Fisher), and extinction coefficients were calculated according to Beer's Law.

     ---------------------------------------------------------
     Wavelength   Molar Extinction   Extinction of 1% solution
     -----------  -----------------  -------------------------
       264 nm      7.64 M^-1 cm^-1            3.29
       256 nm     12.17 M^-1 cm^-1            5.23
       250 nm     16.69 M^-1 cm^-1            7.18
     ---------------------------------------------------------

When we used these extinction coefficients to check a commercial hydrogen
peroxide solution sold as part of an immunoassay kit, we obtained a
concentration of 0.201%, pretty much on the mark.

I hope these constants prove useful to you.  Best regards,  Shaun

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  = Shaun D. Black, PhD   | Internet address:     shaun at jason.uthct.edu = 
  = Dept. of Biochemistry | University of Texas Health Center, at Tyler = 
  = World Wide Web:    http://pegasus.uthct.edu/UTHCT-Home/Welcome.html =
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