Figure 7.

(A) Setup of compact SPR biosensor (left) and the photo and schematic diagram of the biochip (right). (B) Sensing mechanism of compact SPR biosensor. (C) Representative real-time response curve of compact SPR biosensor detecting exosomal PD-L1 in serum sample from a Stage III lung cancer patient. (D) Expression of exosomal PD-L1 in serum samples measured by compact SPR biosensor. ELISA was not able to detect exosomal PD-L1 levels in serum samples. (Cited from reference ¹¹¹, with permission by ACS.)