Comparison of two types of acoustic biosensors to detect immunoreactions: Love-wave sensor working in dynamic mode and QCM working in static mode

A Love-wave device and a PDMS microfluidic chip have been developed in order to measure immunoreactions in liquid media, operating in dynamic mode (continuous flow-through). The obtained results with the above system for the detection of rabbit immunoglobulin by means of an antibody of goat anti-rabbit have been compared with those obtained by the most used acoustic wave device, the quartz crystal microbalance (QCM), which has worked in static mode. It has been demonstrated once again that QCM is an excellent tool as an immunosensor, although the Love-wave device is a good alternative due to its higher sensitivity.The dynamic mode improves the response time and the limit of detection. In addition, the use of microchannels has allowed working with a small sample volume for a long period of time in dynamic mode.On the other hand, a secondary antibody conjugated with gold nanoparticles has been used as a different method to measure the desired concentrations of antigens, obtaining in this case, a greater frequency shift.