To investigate optical responses in (GT)6-SWCNT conjugates, we generated a library of small molecules, using dopamine as our principal compound. The library was designed with variations in truncation, extension, and substitution patterns around the aryl group. The library included conjugated and unconjugated systems, as well as aryl groups with bulky substituents to assess steric effects. Electrondonating and -withdrawing substituents, along with hydrogen bond donors and acceptors, were installed at various positions to explore electronic effects and binding interactions (Fig. ). We measured the fluorescence modulation caused by each analyte in solution phase experiments by recording emission intensity before and after addition of 10 µM of each analyte and reported the relative change in intensity from integrated spectra (∆F/F) (fig. ). To enable comparison across replicates, we normalized the responses to the modulation measured for dopamine under the same experimental conditions. The screening results showed that the majority of the screened analytes produced no optical responses (Fig. IV, 53%). The responses generated by the remaining analytes varied widely, and included optical modulations that are stronger than that produced by dopamine (Fig. ), comparable with dopamine (Fig. II, 6%), and weaker than dopamine (Fig. ).