Supported by the Chemical Measurement and Imaging Program in the Division of Chemistry, and the Instrument Development for Biological Research Program in the Division of Biological Infrastructure, Professor Quan Cheng and his research group at the University of California-Riverside are developing new materials for the detection of biomolecules using surface plasmon resonance (SPR) methods. SPR is a type of measurement where the light reflected from a metal surface or scattered from metal particles of nanometer dimensions can provide information about the molecules or chemical reactions occuring at the metal surface. SPR-based biosensing technology provides effective tools for study of molecular interactions, facilitates the understanding of biological chemistry, and related fields such as drug discovery.
This research focuses on coupling of propagating surface plasmon polaritons (SPPs) and localized surface plasmons in the substrate using the Kretschmann configuration. Several structures such as aligned nanorods and nanovoids are employed to generate new platforms to improve the coupling and thus the detection performance. Specific goals of the research in this work include: 1) developing plasmonic nanoparticle films and 2-D periodic nanostructures as SPR substrates for enhanced label-free analysis; 2) developing ordered porous films on the Au substrate to induce strong optical/plasmonic coupling that improves SPR detection; 3) applying the newly developed SPR substrates for analysis of molecular interactions that involve membrane proteins and aptasensing. LDI-MS analysis with the substrates will be explored as well to systematically evaluate the scope and pragmatism of on-chip orthogonal detection. The highly interdisciplinary nature of this research program also offers diverse opportunities from which students can gain experience when dealing with different problems in surface chemistry, nanotechniques, optics and bioanalytical chemistry.