title: Graphene oxide enhances cellular delivery of hydrophilic small molecules by co-incubation.
abstract: The delivery of bioactive molecules into cells has broad applications in biology and medicine. Polymer-modified graphene oxide (GO) has recently emerged as a de facto noncovalent vehicle for hydrophobic drugs. Here, we investigate a different approach using native GO to deliver hydrophilic molecules by co-incubation in culture. GO adsorption and delivery were systematically studied with a library of 15 molecules synthesized with Gd(III) labels to enable quantitation. Amines were revealed to be a key chemical group for adsorption, while delivery was shown to be quantitatively predictable by molecular adsorption, GO sedimentation, and GO size. GO co-incubation was shown to enhance delivery by up to 13-fold and allowed for a 100-fold increase in molecular incubation concentration compared to the alternative of nanoconjugation. When tested in the application of Gd(III) cellular MRI, these advantages led to a nearly 10-fold improvement in sensitivity over the state-of-the-art. GO co-incubation is an effective method of cellular delivery that is easily adoptable by researchers across all fields.
authors.affiliation: Department of Chemistry, Molecular Biosciences, Neurobiology, Biomedical Engineering, and Radiology, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States.
authors.forename: Andy H
authors.initials: AH
authors.lastname: Hung
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Holbrook
authors.forename: Matthew W
authors.initials: MW
authors.lastname: Rotz
authors.forename: Cameron J
authors.initials: CJ
authors.lastname: Glasscock
authors.forename: Nikhita D
authors.initials: ND
authors.lastname: Mansukhani
authors.forename: Keith W
authors.initials: KW
authors.lastname: MacRenaris
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Manus
authors.forename: Matthew C
authors.initials: MC
authors.lastname: Duch
authors.forename: Kevin T
authors.initials: KT
authors.lastname: Dam
authors.forename: Mark C
authors.initials: MC
authors.lastname: Hersam
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Meade
mesh_terms: D006108:Graphite / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D008279:Magnetic Resonance Imaging; D010087:Oxides / Q000737:chemistry
chemical_list: D010087:Oxides; D006108:Graphite
keywords: adsorption; cell culture; delivery vehicle; gadolinium; graphene oxide; sedimentation; surface interaction