resumo
Electron beam lithography (EBL) was used for preparing nanostructured reduced patterns on the GO paper surface, while preserving its mechanical resistance and flexibility. Different EBL parameters, like dose and time of exposure for patterning were tested. SEM analysis showed the consequent increase of contrast of the reduced stripes on the patterned regions due to the increase of electron beam doses. Moreover, surface potential microscopy experiments also exhibited a clear contrast between the patterned and non-patterned regions. Structural analysis of the patterned paper through X-ray diffraction and nanoindentation showed that the interlayer distance between GO sheets decreases after reduction allowing the increase of the Hardness and Young modulus that makes this material able to be manipulated and integrated on different devices. Furthermore, we also observe that exposed areas to electron beam reduction process show an increase in the electrical conductivity up to 3 x 10(4) times. The developed flexible GO films can have interesting applications such as biosensors or templates for inducing tissue regeneration, by providing a surface with differently patterned cues with contrasting electron mobility. Preliminary in vitro studies with L929 fibroblasts support the cytocompatible nature of this patterned GO paper. (c) 2017 Elsevier Ltd. All rights reserved.
palavras-chave
REDUCED GRAPHENE; NEXT-GENERATION; GRAPHITE OXIDE; STEM-CELLS; FILMS; DIFFERENTIATION; THIN; PHOTOREDUCTION; ARCHITECTURES; INTERFERENCE
categoria
Chemistry; Materials Science
autores
Goncalves, G; Borme, J; Bdkin, I; Gonzalez-Mayorga, A; Irurueta, G; Nogueira, HIS; Serrano, MC; Alpuim, P; Marques, PAAP
nossos autores
Helena Isabel Seguro Nogueira
Professor Auxiliar com Agregaçãoagradecimentos
Gil Goncalves thanks the Fundacao para a Ciencia e a Tecnologia for the PostDoc grant (SFRH/BDP/84419/2012).; P.A.A.P.M. acknowledge the FCT/MCTES for a research contract under the Program Investigator 2013 (IF/00917/2013/CP1162/CT0016) and TEMA - Centre for Mechanical Technology and Automation (UID/EMS/00481/2013), financed by national funds through the FCT/MEC. I.B. wish to acknowledge the Portuguese Foundation for Science and Technology for the financial support (grant IF/00582/2015).; H.I.S.N. acknowledges CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement.; The biological studies of this work have been funded by the Ministerio de Economia y Competitividad and the Fondo Europeo de Desarrollo Regional (MAT2016-78857-R, MINECO/FEDER, UE). AGM and MCS acknowledge ISCIII-MINECO-FEDER for respective contracts. Authors would like to thank Dr M. Teresa Portoles from the Biochemistry and Molecular Biology Department at Universidad Complutense de Madrid for the generous supply of L929 fibroblasts. Dr Jose Angel Rodriguez and Dr Javier Mazario from the Service of Microscopy and Image Analysis at the Hospital Nacional de Paraplejicos are acknowledged for assistance with CLSM studies and Dr Enrique Rodriguez from the Servicio Interdepartamental de Investigacion at the Universidad Autonoma de Madrid for SEM studies.