Electrochemiluminescence device for in-situ and accurate determination of CA153 at the MCF-7 cell surface based on graphene quantum dots loaded surface villous Au nanocage

In our work, low potential and sensitive electrochemiluminescence (ECL) detection for CA153 on MCF-7 cell surface was firstly achieved based on a microfluidic paper-based analytical device. Au nanoflowers were grown in paper working electrode (PWE) to construct the ECL platform for primary antibodies immobilizing. After MCF-7 cells were captured in the modified PWE, and subsequently recognized with ECL signal substance labeled secondary antibodies, the sandwich-type cell sensor was fabricated. Graphene quantum dots (GQDs) loaded surface villous Au nanocages were synthesized as the ECL signal substance, and characterized by scanning electron microscope. The specific villous surface structure for Au nanocage permitted more GQDs being carried and electrons transporting, which largely benefited for the ECL performance. As the un-negligible impendence for MCF-7 cell would definitely influence the ECL signal, CA153 labeled HMEpic cell was used as the control cell to obtain more accurate determination result. This low-cost and fast strategy showed acceptable biocompatibility and stability, and will be promising for cellular immunochemistry.