(559h) Carbon Nanotube Photoluminescence for in vivo Biosensors

Heller, D., Memorial Sloan Kettering Cancer Center
Roxbury, D., University of Rhode Island
Jena, P., Memorial Sloan Kettering Cancer Center
Galassi, T., Memorial Sloan Kettering Cancer Center
Harvey, J., Memorial Sloan-Kettering Cancer Center
Williams, R., Memorial Sloan Kettering Cancer Center
Mittal, J., Lehigh University
Zerze, G. H., Lehigh University
The real-time and spatially-resolved detection and identification of analytes in biological media present important goals for next-generation nanoscale probes and sensors. MicroRNAs and other small oligonucleotides in biofluids are promising disease biomarkers, yet conventional assays require complex processing steps that are unsuitable for point-of-care testing or for implantable or wearable sensors. To this end, we employ the intrinsic near-infrared fluorescence of single-walled carbon nanotubes which is photostable yet sensitive to the immediate environment. Here, we report an engineered carbon-nanotube-based sensor capable of real-time optical quantification of hybridization events of microRNA and other oligonucleotides. The mechanism of the sensor arises from competitive effects between displacement of both oligonucleotide charge groups and water from the nanotube surface, which result in a solvatochromism-like response. The sensor, which allows for detection via single-molecule sensor elements and for multiplexing by using multiple nanotube chiralities, can monitor toehold-based strand-displacement events, which reverse the sensor response and regenerate the sensor complex. We also show that the sensor functions in whole urine and serum, and can non-invasively measure DNA and microRNA after implantation in live mice.