SWCNT PEG-eggs: Single-walled carbon nanotubes in biocompatible shell-crosslinked micelles

Pristine, individualized single-walled carbon nanotubes (SWCNTs) have been noncovalently captured within PEG-terminated block copolymer amphiphiles. Two cross-linkable amphiphiles were evaluated: polyethylene glycol-polyacrylic acid-polystyrene (PEG-PAA-PS) and polyethylene glycol-polybutadiene (PEG-PB). The resulting self-assembled PEG-PAA-PS structures, called PEG-eggs, are freely soluble in water and stable in physiological media. SWCNTs in PEG-eggs retain their intrinsic near-infrared fluorescence, resist exchange with serum proteins, and are non-cytotoxic to mouse macrophage and human renal cells based on in vitro viability assays.