Red fluorescent SiNPs can selectively detect human tumors by TAM uptake mechanism. (A) Fresh tumors and nonmalignant tissues were obtained from patients and incubated ex vivo with red fluorescent SiNPs and imaged with Leica Z16 dissection macroscope after 1 h, and 1, 4, and 7 d. (Scale bar: 1.0 cm.) (B) Confocal images of representative sectioned tumors after 4 d of incubation with SiNPs (red), DAPI tumor nuclei (blue), anti-CD11b (myeloid cells marker), anti-CD14 (monocytes and macrophages marker), and anti-CD68 (myeloid cells marker) antibodies to identify TAMs (yellow). (Scale bar: 50 μm.)