Surface-floating gold nanorod super-aggregates with macroscopic uniformity
- 72 Downloads
We present a simple method for obtaining high-density two- and threedimensional assemblies of gold nanorods (AuNRs) on polymer brush, referred to as “surface-floating super-aggregates”, with uniform distribution spanning macroscopic distances. This was achieved via the single-step immersion of a poly(oligo ethylene glycol methacrylate) brush-containing substrate in a AuNR solution without any form of functionalization. Owing to extensive macroscale plasmonic coupling, we observed for the first time the gradual evolution of a unique sharp peak in addition to the transverse and longitudinal peaks, in this case, in the near-infrared (NIR) region. We also highlight the dynamic nature of these surface-floating super-aggregates, in which the AuNRs spread out when immersed in solution and collapse when dried to facilitate the access of probe molecules for biosensing applications. As a proof of concept, the surface-floating super-aggregates were used for surface-enhanced Raman spectroscopy, with which we detected rhodamine 6G at as low as sub-femtomolar concentrations. Owing to the excellent large-area uniform coverage and extreme simplicity of the fabrication method, such AuNR assemblies can easily be mass-produced and incorporated into cheap biosensors suitable for consumer use in the near future.
Keywordsnanoparticle polymer brush nanocomposites surface-enhanced Raman spectroscopy (SERS)
Unable to display preview. Download preview PDF.
This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Ministry of Education, Science and Technology (No. NRF-2016R1A2B4007209).
- Nepal, D.; Onses, M. S.; Park, K.; Jespersen, M.; Thode, C. J.; Nealey, P. F.; Vaia, R. A. Control over position, orientation, and spacing of arrays of gold nanorods using chemically nanopatterned surfaces and tailored particle-particle-surface interactions. ACS Nano 2012, 6, 5693–5701.CrossRefGoogle Scholar
- Akin, M. S.; Yilmaz, M.; Babur, E.; Ozdemir, B.; Erdogan, H.; Tamer, U.; Demirel, G. Large area uniform deposition of silver nanoparticles through bio-inspired polydopamine coating on silicon nanowire arrays for practical SERS applications. J. Mater. Chem. B 2014, 2, 4894–4900.CrossRefGoogle Scholar
- Alvarez-Puebla, R. A.; Agarwal, A.; Manna, P.; Khanal, B. P.; Aldeanueva-Potel, P.; Carbo-Argibay, E.; Pazos-Perez, N.; Vigderman, L.; Zubarev, E. R.; Kotov, N. A. et al. Gold nanorods 3D-supercrystals as surface enhanced Raman scattering spectroscopy substrates for the rapid detection of scrambled prions. Proc. Natl. Acad. Sci. USA 2011, 108, 8157–8161.CrossRefGoogle Scholar