title: Coating urchinlike gold nanoparticles with polypyrrole thin shells to produce photothermal agents with high stability and photothermal transduction efficiency.
abstract: Photothermal therapy using inorganic nanoparticles (NPs) is a promising technique for the selective treatment of tumor cells because of their capability to convert the absorbed radiation into heat energy. Although anisotropic gold (Au) NPs present an excellent photothermal effect, the poor structural stability during storage and/or upon laser irradiation still limits their practical application as efficient photothermal agents. With the aim of improving the stability, in this work we adopted biocompatible polypyrrole (PPy) as the shell material for coating urchinlike Au NPs. The experimental results indicate that a several nanometer PPy shell is enough to maintain the structural stability of NPs. In comparison to the bare NPs, PPy-coated NPs exhibit improved structural stability toward storage, heat, pH, and laser irradiation. In addition, the thin shell of PPy also enhances the photothermal transduction efficiency (η) of PPy-coated Au NPs, resulting from the absorption of PPy in the red and near-infrared (NIR) regions. For example, the PPy-coated Au NPs with an Au core diameter of 120 nm and a PPy shell of 6.0 nm exhibit an η of 24.0% at 808 nm, which is much higher than that of bare Au NPs (η = 11.0%). As a primary attempt at photothermal therapy, the PPy-coated Au NPs with a 6.0 nm PPy shell exhibit an 80% death rate of Hela cells under 808 nm NIR laser irradiation.
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, PR China.
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Jishu
authors.initials: J
authors.lastname: Han
authors.forename: Tianshu
authors.initials: T
authors.lastname: Xu
authors.forename: Changrun
authors.initials: C
authors.lastname: Guo
authors.forename: Xinyuan
authors.initials: X
authors.lastname: Bu
authors.forename: Hao
authors.initials: H
authors.lastname: Zhang
authors.forename: Liping
authors.initials: L
authors.lastname: Wang
authors.forename: Hongchen
authors.initials: H
authors.lastname: Sun
authors.forename: Bai
authors.initials: B
authors.lastname: Yang
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry* / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D020099:Coated Materials, Biocompatible / Q000737:chemistry* / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004354:Drug Screening Assays, Antitumor; D006046:Gold / Q000737:chemistry*; D006367:HeLa Cells; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D055668:Photochemical Processes; D011108:Polymers / Q000737:chemistry*; D011758:Pyrroles / Q000737:chemistry*; D013329:Structure-Activity Relationship; D013499:Surface Properties; D013696:Temperature; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; D020099:Coated Materials, Biocompatible; D011108:Polymers; D011758:Pyrroles; C067635:polypyrrole; D006046:Gold