Lithium Tantalate Surface Acoustic Wave Sensors for Bio-Analytical Applications

Abstract

A novel chip-based measurement system for marker-free detection of affinity and molecular interaction kinetics has been developed. Lithium tantalate (LiTaO3) based Love-wave sensors are utilized as an alternative to quartz as substrate material in order to improve both the sensitivity and the limit-of-detection (LOD). Monitoring the coupling of thrombin to its antibody at low concentrations 1 nM and 10 nM showed phase changes of Deltaphi = 0.10deg and 0.35deg, respectively, for an active sensor area of 5.6 mm2. We have found that the estimated detection limit for thrombin is on the order of 0.18 nM for our LiTaO3 sensors.