title: Pyropheophorbide A and c(RGDyK) comodified chitosan-wrapped upconversion nanoparticle for targeted near-infrared photodynamic therapy.
abstract: Near-infrared (NIR)-to-visible upconversion nanoparticle (UCNP) has shown promising prospects in photodynamic therapy (PDT) as a drug carrier or energy donor. In this work, a photosensitizer pyropheophorbide a (Ppa) and RGD peptide c(RGDyK) comodified chitosan-wrapped NaYF(4):Yb/Er upconversion nanoparticle UCNP-Ppa-RGD was developed for targeted near-infrared photodynamic therapy. The properties of UCNP-Ppa-RGD, such as morphology, stability, optical spectroscopy and singlet oxygen generation efficiency, were investigated. The results show that covalently linked pyropheophorbide a molecule not only is stable but also retains its spectroscopic and functional properties. In vitro studies confirm a stronger targeting specificity of UCNP-Ppa-RGD to integrin α(v)β(3)-positive U87-MG cells compared with that in the corresponding negative group. The photosensitizer-attached nanostructure exhibited low dark toxicity and high phototoxicity against cancer cells upon 980 nm laser irradiation at an appropriate dosage. These results represent the first demonstration of a highly stable and efficient photosensitizer modified upconversion nanostructure for targeted near-infrared photodynamic therapy of cancer cells. The novel UCNP-Ppa-RGD nanoparticle may provide a powerful alternative for near-infrared photodynamic therapy with an improved tumor targeting specificity.
authors.affiliation: MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou 510631, China.
authors.forename: Aiguo
authors.initials: A
authors.lastname: Zhou
authors.forename: Yanchun
authors.initials: Y
authors.lastname: Wei
authors.forename: Baoyan
authors.initials: B
authors.lastname: Wu
authors.forename: Qun
authors.initials: Q
authors.lastname: Chen
authors.forename: Da
authors.initials: D
authors.lastname: Xing
mesh_terms: D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D048271:Chitosan / Q000737:chemistry*; D002734:Chlorophyll / Q000031:analogs & derivatives* / Q000737:chemistry; D006801:Humans; D053758:Nanoparticles / Q000737:chemistry*; D009842:Oligopeptides / Q000737:chemistry*; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000737:chemistry* / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D009842:Oligopeptides; D017319:Photosensitizing Agents; D017382:Reactive Oxygen Species; D002734:Chlorophyll; C040298:pyropheophorbide a; C047981:arginyl-glycyl-aspartic acid; D048271:Chitosan