Label?free Selective Detection of Protein Markers in the Picomolar Range via a Convenient Voltammetric Sensing Strategy

A convenient strategy for the preparation of label-free selective protein biomarker sensors is presented. After formation a ferrocene terminated monolayer on gold electrode using thiol chemistry, grafting an antifouling phenylalanine layer onto preformed achieved by diazonium chemistry. This provides platform receptor (anti-BSA or anti-CRP) immobilization as well interface. Specific target binding leads to attenuation voltammetric faradaic signal underlying group. Thereby, label-free, selective, detection with highly competitive limits in low (?4) picomolar range both BSA and CRP.