title: Graphene Oxide Based Nanocarrier Combined with a pH-Sensitive Tracer: A Vehicle for Concurrent pH Sensing and pH-Responsive Oligonucleotide Delivery.
abstract: We chemically tuned the oxidation status of graphene oxide (GO) and constructed a GO-based nanoplatform combined with a pH-sensitive fluorescence tracer that is designed for both pH sensing and pH-responsive drug delivery. A series of GOs oxidized to distinct degrees were examined to optimize the adsorption of the model drug, poly dT30. We determined that highly oxidized GO was a superior drug-carrier candidate in vitro when compared to GOs oxidized to lesser degrees. In the cell experiment, the synthesized pH-sensitive rhodamine dye was first applied to monitor cellular pH; under acidic conditions, protonated rhodamine fluoresces at 588 nm (λex=561 nm). When the dT30-GO nanocarrier was introduced into cells, a rhodamine-triggered competition reaction occurred, and this led to the release of the oligonucleotides and the quenching of rhodamine fluorescence by GO. Our results indicate high drug loading (FAM-dT30/GO=25/50 μg/mL) and rapid cellular uptake (<0.5 h) of the nanocarrier which can potentially be used for targeted RNAi delivery to the acidic milieu of tumors.
authors.affiliation: †Department of Applied Chemistry, ‡Center for Interdisciplinary Science (CIS), and §Institute of Molecular Science, National Chiao-Tung University, No. 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan.
authors.forename: Chia-Jung
authors.initials: CJ
authors.lastname: Hsieh
authors.affiliation: †Department of Applied Chemistry, ‡Center for Interdisciplinary Science (CIS), and §Institute of Molecular Science, National Chiao-Tung University, No. 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan.
authors.forename: Yu-Cheng
authors.initials: YC
authors.lastname: Chen
authors.affiliation: †Department of Applied Chemistry, ‡Center for Interdisciplinary Science (CIS), and §Institute of Molecular Science, National Chiao-Tung University, No. 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan.
authors.forename: Pei-Ying
authors.initials: PY
authors.lastname: Hsieh
authors.affiliation: †Department of Applied Chemistry, ‡Center for Interdisciplinary Science (CIS), and §Institute of Molecular Science, National Chiao-Tung University, No. 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan.
authors.forename: Shi-Rong
authors.initials: SR
authors.lastname: Liu
authors.affiliation: †Department of Applied Chemistry, ‡Center for Interdisciplinary Science (CIS), and §Institute of Molecular Science, National Chiao-Tung University, No. 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan.
authors.forename: Shu-Pao
authors.initials: SP
authors.lastname: Wu
authors.affiliation: †Department of Applied Chemistry, ‡Center for Interdisciplinary Science (CIS), and §Institute of Molecular Science, National Chiao-Tung University, No. 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan.
authors.forename: You-Zung
authors.initials: YZ
authors.lastname: Hsieh
authors.affiliation: †Department of Applied Chemistry, ‡Center for Interdisciplinary Science (CIS), and §Institute of Molecular Science, National Chiao-Tung University, No. 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan.
authors.forename: Hsin-Yun
authors.initials: HY
authors.lastname: Hsu
mesh_terms: D000818:Animals; D003692:Delayed-Action Preparations / Q000008:administration & dosage* / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D051379:Mice; D053769:Nanocapsules / Q000008:administration & dosage / Q000737:chemistry* / Q000648:ultrastructure; D010087:Oxides / Q000737:chemistry; D010957:Plasmids / Q000008:administration & dosage* / Q000235:genetics*; D000067996:RAW 264.7 Cells; D012235:Rhodamines / Q000737:chemistry; D013050:Spectrometry, Fluorescence / Q000379:methods; D000068936:Theranostic Nanomedicine / Q000379:methods; D014162:Transfection / Q000379:methods
chemical_list: D003692:Delayed-Action Preparations; D053769:Nanocapsules; D010087:Oxides; D012235:Rhodamines; D006108:Graphite
keywords: graphene oxide; oligonucleotide delivery; pH-responsive drug delivery; pH-sensitive rhodamine; theranostics