An aptasensor for sensitive detection of human breast cancer cells by using porous GO/Au composites and porous PtFe alloy as effective sensing platform and signal amplification labels

A novel aptamer biosensor for cancer cell assay has been reported on the basis of ultrasensitive electrochemical detection. The assay uses the aptamer as a capture probe to recognize and bind the tumor marker on the surface of the cancer cells, forming an aptamer-based sandwich structure for MCF-7 cells detection. Functionalized nanoporous materials, porous graphene oxide/Au composites (GO/Au composites) and porous PtFe alloy have been introduced into the biosensor. Owing to the large surface area and versatile porous structure, the use of nanoporous materials can significantly improve the analysis performance of the biosensors by loading of large amounts of molecules and accelerating diffusion rate. Under the optimized experimental conditions, the proposed aptamer biosensor exhibited excellent analytical performance for MCF-7 cells determination, ranging from 100 to 5.0 x 10(7) cells mL(-1) with the detection limit of 38 cells mL(-1). The biosensor showed good selectivity, acceptable stability and reproducibility, and developed a highly sensitive and selective method for cancer cells detection. (C) 2013 Elsevier B. V. All rights reserved.