Fig. 2

a Characterization of AuNRs before and after conjugation with CB[6] HA. a, b Representative TEM images of CTAB@AuNR (a.1) and CB[6] @AuNR (b.1). AuNR width (a.2 and b.2), length (a.3 and b.3) and aspect ratio (a.4 and b.4). The AuNRs showed an average width of 10.3 ± 0.2 nm, an average length of 40.2 ± 0.4 nm and an aspect ratio of 3.9 ± 0.1. Results are average ± SEM (n = 50). c Amount of CB[6] HA at the surface of AuNR in different CB[6] HA:AuNR ratios determined by the anthrone assay (~ 3252 ± 354 polymer chain/NR for the theoretical ratio of 50.000:1). Absorbance at 780 nm was normalised by the absorbance of AuNRs before ligand exchange. Results are average ± SEM (n = 3). Absorbance spectra (d) and zeta potential (e) of AuNRs before (CTAB@AuNR) and after conjugation with CB[6] HA (CB[6] @AuNR)