developed SERS nanotags based on Ag‐encapsulated Au (Ag–Au) hollow nanospheres with three Raman reporters (MGITC, RBITC, DTDC) positioned in nanogaps to enhance the electromagnetic field.[248] Through conjugation with specific antibodies, these nanotags enabled simultaneous and quantitative detection of multiple breast cancer biomarkers (EpCAM, ErbB2, and CD44) via SERS mapping techniques. This evidence concerns the gene ERBB2 and breast cancer.