Detection of HCG-antigen based on enhanced photoluminescence of hierarchical ZnO arrays

Specific antibody of Human chorionic gonadotrophin (HCG) was conjugated onto hierarchical ZnO arrays through the carbodiimide technique, and the photoluminescence (PL) intensity of ZnO arrays were enhanced linearly with the linked antibody concentration in the range of 40–160 ng/mL, which resulted from the nano sheet structure and rough surface in hierarchical ZnO columns. After the specific combination between antigen and antibody on hierarchical ZnO arrays, the enhanced PL intensity of ZnO arrays was also basically linear with the concentration of HCG antigen. Thus, detection of HCG antigen in the range of 2–20 ng/mL was achieved based on PL intensity enhancement, suggesting that the prepared ZnO arrays are envisioned to be applied in the detection of early tumor markers in future.