A Plasmonic-Photonic Hybrid Fiber-Optic Sensor for Tumor Marker Detection and Heterogeneity Characterizing

The detection of tumor markers played an important role in cancer research and immunotherapy. Despite sensitive detection capabilities offered by current techniques such as ELISA, microfluidic chips, and other liquid biopsy methods, it remained challenging to characterize the heterogeneity of markers in the tumor microenvironment. To meet the sensitive, micron-scale, and easy operating requirements, we proposed a plasmonic-photonic hybrid fiber-optic sensor strategy in this work. Utilizing the coupling between Fabry-Perot interference and LSPR of gold nanourchins on the fiber tip, a high sensitivity of 386.3 nm/RIU was achieved. The performance of the fiber-optic sensor was also verified by PD-L1, a new predictive biomarker for cancer immunotherapy, which demonstrated its potential for application in real-time, label-free quantitative detection of tumor markers and heterogeneity characterizing.