a.) Schematic of high-speed confocal Raman imaging microscope employing galvano mirrors for raster-scanning the laser beam across the specimen. b.) Overlaid Raman spectra of one full raster scan of a cell just after introducing carbon nanotube-containing media (T=0) showing cellular lipid (1450 cm⁻¹) and protein (1004 cm⁻¹) Raman features but no carbon nanotube features. c.) Overlaid Raman spectra of one full raster scan of the same cell at 32.4 minutes after the introduction of nanotube-containing media showing strong nanotube RBM, tangential, IFMs, and disorder modes. Cellular signal is present but dwarfed by the nanotube modes. d.) Aggregate Raman spectrum of nanotubes in the cell showing convoluted Raman peaks. e.) Spectrum of the ss(AT)₁₅ oligonucleotide-suspended carbon nanotube sample used in this study.

a.) Example Raman spectrum of multiple clearly differentiable nanotube RBMs with intensities approaching that of the G-band. The spectrum was spectrally deconvoluted to quantify the RBM, IFM, disorder, and G-band. Inset: Magnified RBM region showing deconvoluted peaks. b.) Raman intensity maps of a single RAW 264.7 macrophage at 32.4 minutes after introducing nanotubes. Each map was compiled using the intensity of a single Raman mode from an endogenous cell-based peak (lipids and proteins), or a nanotube-derived peak (RBMs, IFMs, degradation, and G-band). The cell shape was derived from the lipid peak.

a.) Uptake of several carbon nanotube Raman modes measured within a live macrophage. b.) Relative G-band signal, normalized to the total nanotube-derived Raman signal in the cell, plotted over time. The G-band represents an increasing proportion of total nanotube signal in the cell. The inverse is seen by plotting the RBM signal versus total signal. c-f.) Single frames taken at 32.4 minutes from movies (in ) showing cell-intrinsic features and nanotube-based features within the confines of the cell. g.) Time series of movie frames from showing uptake of two nanotube species, as defined by their RBMs, and the G-band. Earlier images show few G-band features with respect to the total Raman signal, while later images exhibit the opposite.