Antibody-equipped ZnO nanorods highlight tumours

Feb 1, 2012  Increasingly, nanomaterials are being recognized for their potential in biological and medical applications. Compared with bulk substances, they demonstrate unique properties toward cells and tissues, and their ability to detect cancer cells has been shown. Among these materials, ZnO is considered as a particularly promising candidate thanks to its large exciton binding energy, which suggests a higher luminous efficiency than other semiconductor light sources or fluorescence.

Cancer cells tagged with ZnO nanorod probes Researchers from National Taiwan University are using ZnO nanorods bonded to antibodies as cancer cell probes. Their experiments show that ZnO nanorods can be connected to antibodies that target the epidermal growth factor receptor (EGFR), a receptor that frequently overexpresses in squamous cell carcinoma of the head and neck (HNSCC).

 Tumour detection technology  Using ZnO/EGFR antibody probes, the cancer cells can be recognized by the naked eye or under an optical microscope with the help of purple light emission. On the other hand, for cells with less EGFR expression (in this case, Hs68) no purple light is observed as the probes are washed off.As shown by photoluminescent spectra, the peak intensity ratio between the purple light (from ZnO at the wavelength 377 nm) and the green band (from the auto-fluorescence of cells) is much higher with HNSCC, compared with Hs68. The ZnO/EGFR antibody probes have the potential to be applied in surgery for HNSCC to identify cancer cells in real-time. Using the modified ZnO nanorods, cancer cells can be easily excised thanks to the purple light emission from the probes.

About the author The research was conducted by Sheng-Chieh Yang, Yi-Chun Shen and Tzu-Chun Lu (now at Garmin Corp, Taiwan) under the instruction of Prof. JianJang Huang at the Graduate Institute of Photonics and Optoelectronics, National Taiwan University and Prof. Tsung-Lin Yang at the Department of Otolaryngology, National Taiwan University Hospital and College of Medicine, National Taiwan University, Taiwan. Prof. Huang's group focuses on applying nanotechnology to optoelectronics and biophotonics, and Prof. Yang's group focuses on exploring the potential biomarkers and cancer-detecting technology for clinical applications.