title: Theragnostic pH-sensitive gold nanoparticles for the selective surface enhanced Raman scattering and photothermal cancer therapy.
abstract: We report a nanoparticle-based probe that can be used for a "turn-on" theragnostic agent for simultaneous Raman imaging/diagnosis and photothermal therapy. The agent consists of a 10 nm spherical gold nanoparticle (NP) with pH-responsive ligands and Raman probes on the surface. They are engineered to exhibit the surface with both positive and negative charges upon mildly acidic conditions, which subsequently results in rapid aggregations of the gold NPs. This aggregation simultaneously provides hot spots for the SERS probe with the enhancement factor reaching 1.3 × 10(4) and shifts the absorption to far-red and near-infrared (which is optimal for deep tissue penetration) by the coupled plasmon resonances; this shift was successfully exploited for low-threshold photothermal therapy. The theragnostic gold NPs are cancer-specific because they aggregate rapidly and accumulate selectively in cancerous cells. As the result, both Raman imaging and photothermal efficacy were turned on under a cancerous local environment. In addition, the relatively small hydrodynamic size can have the potential for better access to targeted delivery in vivo and facilitated excretion after therapy.
authors.affiliation: School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science & Technology (POSTECH), Hyojadong, Namgu, Pohang, Korea.
authors.forename: Sungwook
authors.initials: S
authors.lastname: Jung
authors.forename: Jutaek
authors.initials: J
authors.lastname: Nam
authors.forename: Sekyu
authors.initials: S
authors.lastname: Hwang
authors.forename: Joonhyuck
authors.initials: J
authors.lastname: Park
authors.forename: Jaehyun
authors.initials: J
authors.lastname: Hur
authors.forename: Kyuhyun
authors.initials: K
authors.lastname: Im
authors.forename: Nokyoung
authors.initials: N
authors.lastname: Park
authors.forename: Sungjee
authors.initials: S
authors.lastname: Kim
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D006046:Gold / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D006979:Hyperthermia, Induced; D053768:Metal Nanoparticles; D051379:Mice; D046529:Microscopy, Electron, Transmission; D009369:Neoplasms / Q000628:therapy*; D010789:Phototherapy / Q000379:methods*; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013499:Surface Properties
chemical_list: D006046:Gold