Ultrasensitive Flow Sensing of a Single Cell UsingGraphene-Based Optical Sensors.

Onthe basis of the polarization-dependent absorption of graphene undertotal internal reflection, we designed a graphene-based optical refractiveindex sensor with high resolution of 1.7 × 10–8and sensitivity of 4.3 × 107mV/RIU, as well asan extensive dynamic range. This highly sensitive graphene opticalsensor enables label-free, live-cell, and highly accurate detectionof a small quantity of cancer cells among normal cells at the single-celllevel and the simultaneous detection and distinction of two cell lineswithout separation. It provides an accurate statistical distributionof normal and cancer cells with fewer cells. This facile and highlysensitive sensing refractive index may expand the practical applicationsof the biosensor. [ABSTRACT FROM AUTHOR]