2025 AIChE Annual Meeting

(145c) Biofunctionalized Carbon Nanotube Hybrids for Modular Near-Infrared Biosensing and Imaging

Authors

Shoichi Nishitani - Presenter, University of California, Berkeley
Markita Landry, Chan Zuckerberg Biohub
Single-walled carbon nanotubes (SWCNTs) exhibit non-photobleaching fluorescence in the near-infrared window, enabling tissue-transparent molecular imaging in both in vivo and ex vivo contexts. This talk will present a set of emerging strategies for dispersing and functionalizing SWCNTs using biopolymers such as single-stranded DNA (ssDNA) and enzymes. These biopolymers serve dual roles: they confer molecular recognition while also enabling aqueous dispersion of otherwise hydrophobic nanotubes by combining hydrophobic anchoring domains with hydrophilic solubilizing motifs. This mutualistic assembly—between biopolymer and SWCNT—enables modular nanosensor design by leveraging target-induced modulation of SWCNT fluorescence to detect biologically relevant analytes including glucose [1], hydrogen peroxide [2], and viral RNA fragments [3].

Our approach integrates both non-covalent (e.g., π–π stacking of ssDNA) and covalent (e.g., defect-free azide-based chemistry) functionalization strategies, each tailored to preserve SWCNT photophysics and biomolecular activity. In parallel, we introduce a redox dye-mediated charge transfer mechanism that offers a versatile and reversible framework for sensitive and selective biosensing through dye–SWCNT fluorescence resonance energy transfer (FRET). These SWCNT–biopolymer hybrids represent a class of bio-mimetic nanomaterials that integrate molecular recognition with nanoscale optical transduction. Their modularity, optical responsiveness, and aqueous compatibility highlight their potential for next-generation biosensing/imaging platforms, spanning from in vitro diagnostics to real-time in vivo molecular imaging.

References

[1] Nishitani et al., Angew. Chem. Int. Ed. 2024, 63, e202311476.

[2] Ledesma, Nishitani et al., Adv. Funct. Mater. 2024, 2316028.

[3] Nishitani et al., Proc. Natl. Acad. Sci. 2025, 122, e2419666122.