title: Near-infrared phosphorescent polymeric nanomicelles: efficient optical probes for tumor imaging and detection.
abstract: We report a formulation of near-infrared (near-IR) phosphorescent polymeric nanomicelles and their use for in vivo high-contrast optical imaging, targeting, and detection of tumors in small animals. Near-IR phosphorescent molecules of Pt(II)-tetraphenyltetranaphthoporphyrin (Pt(TPNP)) were found to maintain their near-IR phosphorescence properties when encapsulated into phospholipid nanomicelles. The prepared phosphorescent micelles are of approximately 100 nm size and are highly stable in aqueous suspensions. A large spectral separation between the Pt(TPNP) absorption, with a peak at approximately 700 nm, and its phosphorescence emission, with a peak at approximately 900 nm, allows a dramatic decrease in the level of background autofluorescence and scattered excitation light in the near-IR spectral range, where the signal from the phosphorescent probe is observed. In vivo animal imaging with subcutaneously xenografted tumor-bearing mice has resulted in high contrast optical images, indicating highly specific accumulation of the phosphorescent micelles into tumors. Using optical imaging with near-IR phosphorescent nanomicelles, detection of smaller, visually undetectable tumors has also been demonstrated.
authors.affiliation: Institute for Lasers, Photonics and Biophotonics, SUNY at Buffalo, Buffalo, New York 14226, USA.
authors.forename: Rajiv
authors.initials: R
authors.lastname: Kumar
authors.forename: Tymish Y
authors.initials: TY
authors.lastname: Ohulchanskyy
authors.forename: Indrajit
authors.initials: I
authors.lastname: Roy
authors.forename: Sandesh K
authors.initials: SK
authors.lastname: Gupta
authors.forename: Carsten
authors.initials: C
authors.lastname: Borek
authors.forename: Mark E
authors.initials: ME
authors.lastname: Thompson
authors.forename: Paras N
authors.initials: PN
authors.lastname: Prasad
mesh_terms: D000818:Animals; D006801:Humans; D008027:Light; D049449:Luminescence; D008665:Metalloporphyrins / Q000737:chemistry; D051379:Mice; D008819:Mice, Nude; D008823:Micelles; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods*; D009368:Neoplasm Transplantation; D009369:Neoplasms / Q000175:diagnosis* / Q000473:pathology; D010758:Phosphorus / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D012542:Scattering, Radiation; D013055:Spectrophotometry, Infrared / Q000379:methods
chemical_list: D008665:Metalloporphyrins; D008823:Micelles; D011108:Polymers; D010758:Phosphorus