abstract
The major limitation in the development of hybrids based on graphene oxide (GO) and porphyrins is their dispersibility and stability in aqueous systems due to the hydrophobic character induced by porphyrins. Most of the previous approaches reported the direct functionalization of GO with polyethylene glycol (PEG) chains followed by the self-assembly of porphyrins by pi-pi interactions. Here, new hybrids were prepared using porphyrins previously functionalized with different number/types of glycol branches to be covalently attached through esterification to the carboxyl groups of GO sheets of nano-metric dimensions. The number of the glycol chains and its relative position in the porphyrin core showed to be fundamental to improve the hybrids dispersion and stability in aqueous solutions. The best performing hybrids were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared, UV-Vis absorption and fluorescence spectroscopy. The in vitro biocompatibility assessment of these hybrids was conducted using human Saos-2 cells. Their effects on cell proliferation and viability, the generation of reactive oxygen species as well as the cell morphology after cell uptake were analysed. The results demonstrate the biocompatibility of these hybrid nano-materials with human Saos-2 cells, which is very promising for future application in biomedicine namely in cancer therapy. (C) 2018 Elsevier Ltd. All rights reserved.
keywords
NANO-GRAPHENE OXIDE; NONLINEAR-OPTICAL PROPERTIES; PHOTODYNAMIC THERAPY; PHOTOTHERMAL THERAPY; PORPHYRIN; CANCER; FUNCTIONALIZATION; NANOPARTICLES; POLYMERS; CELLS
subject category
Chemistry; Materials Science
authors
Santos, CIM; Goncalves, G; Cicuendez, M; Mariz, I; Silva, VS; Oliveira, H; Campos, F; Vieira, SI; Marques, PAAP; Macoas, EMS; Neves, MGPMS; Martinho, JMG
our authors
Helena Oliveira
Post-Doc Fellowship
Monica Cicuéndez Maroto
Post-Doc FellowshipGroups
acknowledgements
Authors are grateful to Fundacao para a Ciencia e a Tecnologia, European Union, QREN, FEDER and COMPETE for funding the QOPNA, TEMA, CQFM and iBiMED research units (project Pest-C/QUI/UI0062/2013, UID/EMS/00481/2013, UID/NAN/50024/2013, UID/BIM/04501/2013) and the Portuguese National NMR and PPBI Bioimaging Networks, also supported by funds from FCT (POCI-01-0145-FEDER-022122). FCT is acknowledged for the Post-Doctoral grants of C.I.M.S., M.C., I.M., V.S.S. and H.O. and for supporting the individual work contract of E.M. and P.A.A.P.M within the Investigador FCT program (SFRH/BPD/105478/2014, SFRH/BPD/101468/2014, SFRH/BPD/75782/2011, SFRH/BPD/110269/2015, SFRH/BPD/111736/2015, IF/00759/2013 and IF/00917/2013).