Controlled Quantum Well Formation on DNA-Wrapped Carbon Nanotubes via Peroxide-Mediated Aryl Diazonium Reduction

Quantum well defect-modified single-walled carbon nanotubes are nanomaterials with wide-ranging applications in biosensing, imaging, quantum computing, and catalysis. The most common method for covalent functionalization of nanotubes for biosensing applications involves reactions with aryl diazonium salts to generate sp³ aryl defect sites, commonly followed by wrapping with single-stranded DNA for aqueous dispersion. We describe herein a rapid aryl diazonium functionalization reaction directly compatible with DNA-wrapped nanotubes, mediated by hydrogen peroxide. The reaction uses mild aqueous conditions at physiological pH and can be easily monitored in real-time via fluorescence analysis to control the degree of functionalization. Overall, this reaction greatly simplifies the production of covalently functionalized DNA-wrapped carbon nanotubes, expanding their potential for industrial and biomedical applications.