The Antibody-Free Recognition of Cancer Cells Using Plasmonic Biosensor Platforms with the Anisotropic Resonant Metasurfaces.

It is vital and promising for portable and disposable biosensing devices to achieve on-site detection and analysis of cancer cells. Although traditional labelling techniques provide an accurate quantitative measurement, the complicated cell staining and high-cost measurements limit its further development. Here, we demonstrate a non-immune biosensing technology. The plasmonic biosensors which is based on anisotropic resonant split ring resonators in terahertz range successfully realize the antibody-free recognition of cancer cells. The dependences of Δf and fitted phase slope (FPS) on the cancer cell concentration at different polarizations give new perspective in hexagonal radar maps. The results indicate that the lung cancer cell A549 and liver cancer cell HepG2 can be distinguished and determined simply based on the enclosed shape in the radar maps without any antibody introduction. The minimum concentration of identification reduces as low as 1×104 cells/ml and such identification can be kept valid in a large range of cell concentration, ranging from 104 to 105. The construction of two-dimensional extinction intensity cards of corresponding cancer cells based on the wavelet transform method also supplies corresponding information for the antibody-free recognition and determination of two cancer cells. Our plasmonic MBs show a great potential in the determination and recognition of label-free cancer cells, being an alternative to non-immune biosensing technology.