Biological systems hydrogen peroxide determination

Two methods were examined for digestion of biological samples prior to trace element analysis. In the first one a nitric acid-hydrogen peroxide-hydrofluoric acid mixture was used in an open system, and in the second one nitric acid in a closed Teflon bomb. The latter method was superior for Ge determination, however, germanium was lost whenever hydrogen fluoride had to be added for disolving sihcious material. End analysis by ICP-AES was used for Ge concentrations in the Xg/g range13. 

In an early application, an enzyme electrode system was reported for the determination of creatinine and creatine, using a combination of creatinine amidohy-drolase, creatine amidinohydrolase and sarcosine oxidase, co-immobilized on an asymmetric cellulose acetate membrane. Thus, the hydrogen peroxide produced was detected to give a quantitative measure of creatine and creatinine in biological fluids [70]. 

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