Improved stability of aluminum surface plasmon resonance sensor by protective gold layer

The surface plasmon resonance (SPR) sensing in the ultraviolet (UV) region, achieved through the optimization of aluminum (Al) film conditions, has attracted attention due to its heightened energy levels and more plentiful molecular electronic transitions compared to the visible region. In this research, the stability of the UV-SPR sensor is improved by applying a protective thin layer of gold (Au) onto the Al film. This reduces spectral alterations observed when the Al film was uncoated in water pre and post flow system measurements. This exploration presents the initial experimental confirmation of the reliability of Al -Au bilayer coatings as SPR sensors in the UV region, highlighting advancements in UV-SPR sensor technology.