Carbon Nanotube Quantum Defect Photoluminescence Modulation for Biosensors

Covalent sp3 defects on single-walled carbon nanotubes (SWCNTs), often called organic color centers (OCCs) have been explored for their photoluminescent properties, including the potential for introducing new emission bands, increasing quantum yield, and introducing new chemical sensitivities. The application of OCCs for biomedical applications requires new methods to synthesize them via covalent chemistry, to control their biological interactions/biocompatibility via supramolecular interactions with excipients, and to measure their emission in biological environments. We have found specific utilities of OCCs for the detection of chemical phenomena where SWCNT photoluminescence is normally relatively insensitive, such pH changes in the physiologic range. We developed OCCs to measure lysosomal pH in live cells and in vivo, enabling new biological discoveries. We also developed OCC-based biosensors for cancer detection. We believe that OCCs will facilitate the development of an important class of sensors for biomedical applications.