CXCR4 and triple-negative breast carcinoma: Innate radiolabeling via the explicit addition of 64Cu to Cu NC conjugated with FC131 peptide (64Cu-CuNCs-FC131) provided a high specific activity for sensitivity and precision in detection via high-affinity binding with FC131-receptor (CXCR4)-positive triple negative breast cancer (TNBC) patient-derived xenograft mouse models and human TNBC tissues.