Aptamers as molecular recognition elements for electrical nanobiosensors

Recent advances in nanotechnology have enabled the development of nanoscale sensors that outperform conventional biosensors. This review summarizes the nanoscale biosensors that use aptamers as molecular recognition elements. The advantages of aptamers over antibodies as sensors are highlighted. These advantages are especially apparent with electrical sensors such as electrochemical sensors or those using field-effect transistors

Energy harvesting with vibrating shoe-mounted piezoelectric cantilevers

This chapter presents a study on energy harvesting from human walking via piezoelectric vibrating bimorphs. Heel accelerations are measured and compared with data from literature. All relevant features are summarized in a typical (standard) acceleration signal, used as a reference input in numerical simulations. The transient electromechanical response (beam deflection, output voltage, and average output power) of a shoe-mounted rectangular scavenger excited by the standard acceleration is calculated by numerical simulations. Step-by-step numerical integration is used, as the input is a non-sinusoidal signal and explicit analytical solution is not available. Results from simulations are also validated with measurements on a real shoe-mounted device. A sensitivity analysis is finally performed to find alternative scavenger configurations that could provide increased power levels. Acceptability criteria based on imposed geometrical constraints and material strength limits are also checked. This analysis allows a rapid screening of harvesting performance among a wide set of different scavenger configurations, which allows finding the one providing the largest output power