Biosensor packaging — adaptation of the surface modification procedure

Biosensor packaging is a useful means to interface the biosensor with the surroundings while ensuring its integrity and performance. However, such a packaging typically enlarges the chemical environment of the biosensor component on which surface modification procedures–required for applying the sensing layer on the transducer device–may have an impact. Using the example of surface acoustic wave (SAW) devices integrated in polycarbonate (PC) housings we show how the common surface modification procedure affects the biosensor housing and how the modification steps have to be altered to be suitable for those SAW biosensor chips. Besides chemical stability, it has to be taken into account that modification steps may influence the morphology of the sensing layer resulting in changes of the SAW biosensor signal response in the subsequent assay.