Differential method for undisturbed detection of 17β-estradiol using an integrated aptameric graphene nanosensor

This paper presents a differential method based on the graphene field effect biosensor for the rapid and specific quantification of environmental pollution-related biochemical analyte. Selectively functionalizing one of the two identical graphene channels and calibrating the sensitivity difference of the two channels allowed us to extract analyte binding-induced signals by subtracting irregular and unpredictable background. Using this method we demonstrated real-time monitoring of 17β-estradiol in electrolytes with varying pH value. This work represents important progress of graphene field effect sensors toward use with complex real samples.