Research and development of an integrated multi-parameter quartz crystal microbalance and surface plasmon resonance system

Abstract

We developed a multi-parameter detection system that integrates both a quartz crystal microbalance (QCM) and a surface plasma resonance (SPR) system. A QCM is known to possess the capabilities of measuring both mass loading by frequency shift and stiffness by damping factor of the adsorption layer. However, the mass measured by using a QCM includes not only the true mass of the adsorption layer but also the water. On the other hand, a SPR is a well known technique which can be used to measure the true mass loading of the adsorption layer. By integrating these two techniques, we can simultaneously measure properties such as stiffness, conformation, and mass loading of the adsorption layer. To simplify the chip manufacturing procedures, this new detection system adopts a prism couple method which consists of a He-Ne laser, a prism, quartz and a power meter. In consideration of the light transmission issue, one side of the quartz was coated with ITO instead of gold. Preliminary results showed that this set-up can perform QCM and SPR techniques simultaneously. The experimental results matched well with the theoretical predictions.