Versatile SERS sensing based on black silicon Gediminas Seniutinas 1,2,6 , Gediminas Gervinskas 1,2 , Roli Verma 3,4 , Banshi D. Gupta 3 , Florian Lapierre 2,5 , Paul R. Stoddart 1 , Felix Clark 1 , Sally L. McArthur 1 and Saulius Juodkazis 1,2,∗ 1 Centre for Micro-Photonics and Industrial Research Institute Swinburne, Faculty of Science, Engineering and Technology, Swinburne University of Technology, Hawthorn, VIC, 3122, Australia 2 Melbourne Centre for Nanofabrication, 151 Wellington Road, Clayton, VIC 3168, Australia 3 Department of Physics, Indian institute of Technology Delhi, New Delhi 110016, India 4 School of Chemistry, Raymond and Beverly Sackler, Faculty of Exact Sciences, Tel Aviv University, Tel Aviv-6887801, Israel 5 School of Electrical and Computer Engineering, RMIT University, 124 La Trobe St., Melbourne, Victoria 3000, Australia 6 GSeniutinas@swin.edu.au ∗ SJuodkazis@swin.edu.au Abstract: Black Si (b-Si) with gold or silver metal coating has been shown to be an extremely effective substrate for surface-enhanced Raman scattering (SERS). Here, we demonstrate that it is also a highly versatile SERS platform, as it supports a wide range of surface functionalizations. In particular, we report the use of a molecularly imprinted polymer (MIP) coating and a hydrophobic coating on b-Si to establish two different sensing modalities. First, using a MIP layer on Au-coated b-Si, we show selective sensing of two closely related varieties of tetracycline. Second, a hydropho- bic coating was used to concentrate the analyte adsorbed on gold colloidal nanoparticles, thus increasing the sensitivity of the measurement by an order of magnitude. In this experiment, Au nanoparticles and analyte were mixed just before SERS measurements and were concentrated by drop-drying on the super-hydrophobic b-Si. These approaches are promising for SERS measurements that are sensitive to the aging of bare plasmonic metal-coated substrates. © 2015 Optical Society of America OCIS codes: (280.1415) Biological sensing and sensors; (220.4241) Nanostructure fabrication; (240.6695) Surface-enhanced Raman scattering; (240.6680) Surface plasmons; (160.4236) Nanomaterials. References and links 1. B. Zhang, H. Wang, L. Lu, K. Ai, G. Zhang, and X. Cheng, “Large-area silver-coated silicon nanowire arrays for molecular sensing using surface-enhanced Raman spectroscopy,” Adv. Func. Mat. 18, 2348–2355 (2008). 2. S. K. Srivastava, A. Shalabney, I. Khalaila, C. R. Gr¨ uner, B. Rauschenbach, and I. Abdulhalim, “SERS biosensor using metallic nano-sculptured thin films for the detection of endocrine disrupting compound biomarker vitel- logenin,” Small 10, 3579–3587 (2014). 3. A. Chou, E. Jaatinen, R. Buividas, G. Seniutinas, S. Juodkazis, E. L. Izake, and P. M. Fredericks, “SERS substrate for detection of explosives,” Nanoscale 4, 7419–7424 (2012). 4. W. Premasiri, D. Moir, M. Klempner, N. Krieger, G. Jones, and L. Ziegler, “Characterization of the surface enhanced Raman scattering (SERS) of bacteria,” J. Phys. Chem. B 109, 312–320 (2005). #229123 - $15.00 USD Received 10 Dec 2014; revised 15 Feb 2015; accepted 16 Feb 2015; published 4 Mar 2015 © 2015 OSA 9 Mar 2015 | Vol. 23, No. 5 | DOI:10.1364/OE.23.006763 | OPTICS EXPRESS 6763