Functionalized reduced graphene oxide with aptamer macroarray for cancer cell capture and fluorescence detection.

Abstract

Anintegrated aptamer macroarray functionalized with reduced graphene oxide (rGO) to specifically capture and sensitively detect cancer cellsis reported. The capture for cancer cells is based on effective recognition of the modified rGO surface through theaptamer against epithelial cell adhesion molecule (EpCAM). The rough structure of rGO enhances morphologic interactions between rGO film interface and the cancer cells, while super-hydrophilicity of modified rGO hinders nonspecific cell capture. The synergistic interactions offer the aptamer macroarray high efficiency of cancer cell capture. By means of a turn-on fluorescence strategy based on the conformation change of theaptamer induced by the target recognition, the enriched cancer cells can be directly read out at excitation/emission wavelengths of 550/680nm without washing, separation, and dying steps. The working range is1 × 102 to 2 × 104 cells per mL with a detection limit of 22 cells per mL. The results indicate that the aptamer macroarray has a considerable foreground for early diagnosis, therapy, and monitoring of cancer. Graphical abstract.