title: Porphysome nanovesicles generated by porphyrin bilayers for use as multimodal biophotonic contrast agents.
abstract: Optically active nanomaterials promise to advance a range of biophotonic techniques through nanoscale optical effects and integration of multiple imaging and therapeutic modalities. Here, we report the development of porphysomes; nanovesicles formed from self-assembled porphyrin bilayers that generated large, tunable extinction coefficients, structure-dependent fluorescence self-quenching and unique photothermal and photoacoustic properties. Porphysomes enabled the sensitive visualization of lymphatic systems using photoacoustic tomography. Near-infrared fluorescence generation could be restored on dissociation, creating opportunities for low-background fluorescence imaging. As a result of their organic nature, porphysomes were enzymatically biodegradable and induced minimal acute toxicity in mice with intravenous doses of 1,000 mg kg(-1). In a similar manner to liposomes, the large aqueous core of porphysomes could be passively or actively loaded. Following systemic administration, porphysomes accumulated in tumours of xenograft-bearing mice and laser irradiation induced photothermal tumour ablation. The optical properties and biocompatibility of porphysomes demonstrate the multimodal potential of organic nanoparticles for biophotonic imaging and therapy.
authors.affiliation: Institute of Biomaterials and Biomedical Engineering, University of Toronto, Ontario M5G 1L7, Canada.
authors.forename: Jonathan F
authors.initials: JF
authors.lastname: Lovell
authors.forename: Cheng S
authors.initials: CS
authors.lastname: Jin
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Huynh
authors.forename: Honglin
authors.initials: H
authors.lastname: Jin
authors.forename: Chulhong
authors.initials: C
authors.lastname: Kim
authors.forename: John L
authors.initials: JL
authors.lastname: Rubinstein
authors.forename: Warren C W
authors.initials: WC
authors.lastname: Chan
authors.forename: Weiguo
authors.initials: W
authors.lastname: Cao
authors.forename: Lihong V
authors.initials: LV
authors.lastname: Wang
authors.forename: Gang
authors.initials: G
authors.lastname: Zheng
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000009:adverse effects / Q000737:chemistry; D003287:Contrast Media / Q000009:adverse effects / Q000737:chemistry; D008422:Materials Testing; D051379:Mice; D049329:Nanostructures / Q000009:adverse effects / Q000737:chemistry; D009374:Neoplasms, Experimental / Q000175:diagnosis / Q000532:radiotherapy; D055095:Optics and Photonics / Q000295:instrumentation; D011166:Porphyrins / Q000009:adverse effects / Q000737:chemistry; D041622:Tomography, Optical / Q000295:instrumentation; D014183:Transplantation, Heterologous
chemical_list: D001672:Biocompatible Materials; D003287:Contrast Media; D011166:Porphyrins