ZnO for performance enhancement of surface plasmon resonance biosensor: A review

This paper reviews Kretschmann-based SPR sensor utilizing ZnO thin films and nanostructures for performance enhancement. The advancement in surface plasmon resonance technology relies on low-cost, high sensitivity and high selectivity sensor. Metal oxide has been incorporated in SPR sensor to be used for detection of biological and chemical compounds. ZnO as one of the metal oxides is an attractive material due to its unique physical and optical properties. Numerous techniques for fabrication and characterization of ZnO on SPR gold substrate have been studied. The mechanism for gas and biomolecules detection depends on their interaction with ZnO surface, which is mainly attributed to the high isoelectric point of ZnO. There are several types of ZnO nanostructures which have been employed for SPR application based on the Kretschmann configuration. In future, the thin film and nanostructures of ZnO have potential applications for miniature design, robust, high sensitivity, and low-cost portable type of SPR biosensor to be used for on-site testing in real-time and label-free manner.