Engineered peptide-cell membrane interfaces for ultrasensitive and selective detection of ERBB2

Biosensors hold great promise for rapid clinical diagnosis of cancer at a curable stage of the disease. However, traditional bioassays face challenges such as instability and low selectivity when applied to complex samples. Herein, inspired by the structure and functions of natural cell membranes, we fabricated an ultrasensitive and selective sensor of human epidermal growth factor receptor 2 (ERBB2) in serum based on the engineered peptide membrane interfaces. The polyethylene glycol (PEG) and its derivatives fixed on the Au surface as support layers, on which the phospholipid and multifunctional peptides are applied to construct a hydration layer for antifouling. The engineered peptide membrane interfaces forming a structure with flow recognition, high hydrophilicity and stability. The low nonspecific adsorption at the cell membrane interface based on engineered peptides was achieved by PEG and its derivatives as well as engineered peptide membrane, enabling selective detection in complex serum samples. The fabricated sensor demonstrates good stability and a remarkable limit of detection value of 0.21 ng/mL for ERBB2. Thus, there is great potential for the application of this engineered peptide-cell membrane strategy in further biomimetic interface construction in cell or protein analysis.