Photosensitizer Loaded Nano-Graphene for Multimodality Imaging Guided Tumor Photodynamic Therapy

Abstract

Graphene, a 2-dimensional carbon nanomaterial, has attracted wide attention in biomedical applications, owing to its intrinsic physical and chemical properties. In this work, a photosensitizer molecule, 2-(1-hexyloxyethyl)-2-devinyl pyropheophorbide-alpha (HPPH or Photochlor®), is loaded onto polyethylene glycol (PEG)-functionalized graphene oxide (GO) via supramolecular π-π stacking. The obtained GO-PEG-HPPH complex shows high HPPH loading efficiency. The in vivo distribution and delivery were tracked by fluorescence imaging as well as positron emission tomography (PET) after radiolabeling of HPPH with 64Cu. Compared with free HPPH, GO-PEG-HPPH offers dramatically improved photodynamic cancer cell killing efficacy due to the increased tumor delivery of HPPH. Our study identifies a role for graphene as a carrier of PDT agents to improve PDT efficacy and increase long-term survival following treatment.

Phthalocyanine-loaded graphene nanoplatform for imaging-guided combinatorial phototherapy

“…26 A noncovalent method was used to immobilize photosensitizers onto graphene via π-π stacking, which caused a significant reduction in the fluorescence and ROS generation as a result of a π-π stacking interaction with graphene. 21,22,26,27 To overcome the aforementioned obstacles, we developed a novel ovarian cancer-targeted nanomedicine platform that preserves fluorescence imaging and ROS-generating capabilities of the photosensitizer immobilized on the graphene surface. In our design, graphene nanosheets were chemically conjugated with polypropylenimine generation 4 (PPIG4) dendrimer loaded with silicon Pc derivative to produce a LOGr-Pc-PPIG4 complex ( Figure 1).…”

Smart Supramolecular Nanosystems for Bioimaging and Drug Delivery

“…[61] In this system, GO-PEG nanoplatform increased uptake of the HPPH into the tumor cells, and promoted significantly PDT efficacy on cancer cells with 4 mW/cm 671 nm laser irradiation for 3 min. The GO-PEG-HPPH complex showed high tumor selectivity.…”

Graphene-Based Nanomaterials for Theranostic Applications

“…162 Rong et al demonstrated bimodal°uorescence/PET imaging guided photodynamic therapy of tumors using PEGylated GO sheets loaded with a radiolabeled photosensitizer 64 Cu -HPPH. 163 Similarly, in a separate study, Yan et al demonstrated bimodal°uorescence/PA imaging guided combined photothermal-photodynamic therapy of tumors using PEGylated GO sheets loaded with DVDMS ( Fig. 7(ii)).…”