• 文献标题:   Direct growth of few-layer graphene on AlN-based resonators for high-sensitivity gravimetric biosensors
  • 文献类型:   Article
  • 作  者:   OLIVARES J, MIREA T, GORDILLODAGALLIER L, MARCO B, ESCOLANO JM, CLEMENT M, IBORRA E
  • 作者关键词:   biomolecule detection, graphene integration, gravimetric biosensor, surface functionalization
  • 出版物名称:   BEILSTEIN JOURNAL OF NANOTECHNOLOGY
  • ISSN:   2190-4286
  • 通讯作者地址:   Univ Politecn Madrid
  • 被引频次:   0
  • DOI:   10.3762/bjnano.10.98
  • 出版年:   2019

▎ 摘  要

We present the successful growth of few-layer graphene on top of AlN-based solidly mounted resonators (SMR) using a low-temperature chemical vapour deposition (CVD) process assisted by Ni catalysts, and its effective bio-functionalization with antibodies. The SMRs are manufactured on top of fully insulating AlN/SiO2 acoustic mirrors able to withstand the temperatures reached during the CVD growth of graphene (up to 650 degrees C). The active AlN films, purposely grown with the c-axis tilted, effectively excite shear modes displaying excellent in-liquid performance, with electromechanical coupling and quality factors of around 3% and 150, respectively, which barely vary after graphene integration. Raman spectra reveal that the as-grown graphene is composed of less than five weakly coupled layers with a low density of defects. Two functionalization protocols of the graphene are proposed. The first one, based on a covalent binding approach, starts with a low-damage O-2 plasma treatment that introduces a controlled density of defects in graphene, including carboxylic groups. After that, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride/Nhydroxysuccinimide (EDC/NHS) chemistry is used to covalently bind streptavidin molecules to the surface of the sensors. The second functionalization protocol is based on the non-covalent bonding of streptavidin on hydrophobic graphene surfaces. The two protocols end with the effective bonding of biotinylated anti-IgG antibodies to the streptavidin, which leaves the surface of the devices ready for possible IgG detection.