Background: Because H2O2 is generated by various oxidase-catalyzed reactions, a highly sensitive determination method of
H2O2 is applicable to measurements of low levels of various oxidases and their substrates such as glucose, lactate,
glutamate, urate, xanthine, choline, cholesterol and NADPH. We propose herein a new, highly sensitive method for the
measurement of H2O2 and glucose using fluorescence correlation spectroscopy (FCS).