Tumor detection strategy using ZnO light-emitting nanoprobes

Traditional methods of detecting cancer cells, such as fluorescence, have their limits and can hardly be used for identification during tumor resection. Here we report an alternative tumor detection technology using ZnO nanorods bonded to antibodies as cancer cell probes. Our experiment shows that antibodies toward epidermal growth factor receptor (EGFR) can be connected to ZnO nanorods and to EGFR receptors of SCC (squamous cell carcinoma). The cancer cell can be recognized by the naked eye or an optical microscope with the help of purple light emission from ZnO/EGFR antibody probes. On the other hand, for cells with less EGFR expression, in our case Hs68, no purple light was observed as the probes were washed off. From the photoluminescent spectra, the peak intensity ratio between the purple light (from ZnO at the wavelength 377 nm) and the green band (from the autofluorescence of cells) is much higher with the presence in SCC, as compared with Hs68. The ZnO/EGFR antibody probes have the potential to be applied to surgery for real-time tumor cell identification. The cancer cells will be excised with the help of purple light emission.