(a) Fabrication steps involved in Love wave biosensor. Reproduced with permission from F. Zhang et al. [272], Sensors; published by MDPI, 2015 (open access). (b) Fabricated Love wave device with an Au electrode and sensing area and SiO2 guide layer on quartz with a reference channel [273]. Reproduced with permission from Xi Zhang et al., Sensors and Actuators B: Chemical; published by Elsevier, 2015. (c) SAW biosensor integrated with PDMS microfluidic channels [271]. Reproduced with permission from Xi Zhang et al., Sensors and Actuators B: Chemical; published by Elsevier, 2014. (d) Fabrication steps for an FPW biosensor with a ZnO piezoelectric layer [247,274]. Reproduced with permission from I.-Y. Huang et al. [247], Sensors and Actuators B: Chemical; published by Elsevier, 2008.