Analytical grade toluene

Graphite powder was supplied by Sigma-Aldrich. Pyridinium tribromide (PyBr₃, TCI) and polyethylenimine branched (PEI, Mw ~25,000, Sigma-Aldrich) were used as received. Single-walled carbon nanotubes (SWCNTs) powder was obtained from SouthWest Nanotechnologies Inc. Triton X-100 were purchased from Golden Innovation Business Co. Ltd. and used for SWCNTs’ dispersion. Analytical grade toluene, Dimethyl sulfoxide (DMSO) and ethanol were purchased from Sigma-Aldrich and used without further purification. The HeLa cell lines were purchased from Food Industry Research and Development Institute (Taiwan). The HeLa cells were grown in the environment of Dulbecco’s Modified Eagle Medium (cat. no. 11885, Invitrogen) at 37 °C with 5% CO₂ humidified atmosphere.

Poly (styrene-2-vinylpyridine) (PS-b-P2VP) (M_n (PS) = 50,000 g mol⁻¹; M_n (P2VP) = 16,500 g mol⁻¹; M_w/M_n = 1.06) was obtained from Polymer Source Inc. Sodium dodecyl sulfate (SDS), dopamine hydrochloride, Gold(III) chloride trihydrate (HAuCl₄·3H₂O), analytical grade toluene, ethanol, 4-nitrophenol (Nip), and sodium borohydride (NaBH₄) were purchased from Sigma-Aldrich and used as received. De-ionized water was used for all aqueous solutions. Tetrahydrofuran (THF) was purchased from Fisher Scientific UK and used as received.