Multiplexed detection of protein markers with silicon nanowire FET and sol-gel matrix

A new modified top-down based fabrication method has been developed to obtain highly ordered silicon nanowire (SiNW) arrays. With this method, we could produce as many as 500 chips (size dependable) in an 8 inch wafer. The immobilization of multiple proteins on each chip was performed by spotting sol/gel materials encapsulating antibodies on the different regions. The most commonly used protein markers in clinics, such as C-reactive protein (CRP) and prostate specific antigen (PSA), were systematically entrapped in sol-gel materials and used for multiplexed testing. Upon formation, the electrical signal of different concentrations of CRP and PSA could be simultaneously determined in the range of 0.12 ~ 10 ng/mL and 0.18 ~ 8.87 ng/mL, respectively.