(557a) Environmental Effects on DNA Binding to Single-Wall Carbon Nanotubes

Single-wall carbon nanotubes (SWCNTs) are a family of molecules with 1D tubular nanostructures that have defined handedness and helicity. Each SWCNT species corresponds to a defined set of (n, m) chiral indices that possess unique optical, electrical, thermal, and mechanical properties. Recently, carbon nanotube sorting of DNA-wrapped SWCNT (DNA-SWCNT) with defined structures and properties has been achieved via polymer aqueous two-phase (ATP) extraction. Particularly, semiconducting SWCNTs emit excitonic fluorescence at specific short-wave infrared (SWIR), where sharp emission bands (≈ 20 nm) can be detected efficiently in complex biological environments. In this work, we investigated the DNA binding to a specific SWCNT by comparing the spectral shift and fluorescence intensity in the SWIR under different environments. Various environmental conditions include pH, the addition of surfactant molecules, and different dispersion media. This study will enable us to identify stable hybrids of DNA-SWCNTs in complex environments which can be utilized for developing applications of SWCNTs in biological imaging and sensing in the SWIR.