Patent ID: 8796625

Claim:
A method comprising: measuring a first absorbance value of a composition comprising a charge transfer complex of single walled carbon nanotubes and H 2 O 2 at one or more wavelengths in the near infra-red; adding a sample to the composition; subsequently measuring a second absorbance value of the composition at the one or more wavelengths; and determining the difference between the first and second absorbance values; wherein the difference between the first and second absorbance values is an indication of the antioxidant concentration or the antioxidant capacity of the sample; wherein the composition comprises H 2 O 2 in excess such that some of the H 2 O 2 molecules are part of the charge transfer complex and some of the H 2 O 2 molecules are not part of the charge transfer complex prior to adding the sample to the composition.