We have described a novel experimental technique to separate nanotubes from other unwanted carbon species in arc generated carbon soot. A conjugated polymer was used to bind to nanotubes in solution. The resultant hybrid was soluble while extraneous carbon material formed a sediment at the bottom of the sample bottle. This process was monitored using electron paramagnetic resonance (EPR) which showed that 63% of nanotubes were kept in solution while 98.1% of impurities were rejected. This allowed the calculation of the nanotube content in the carbon soot using EPR and thermo-gravitational analysis (TGA) yielding a purity value of 34% for the soot used in this study. This is compatible with estimates made using electron microscopy.