Patent attributes
The present invention features the application of a simple, inductively-coupled measurement system into the cap of standard laboratory sample tubes, thus enabling continuous, wireless ionic sensing of a bevy of samples. The system may be powered by a compact Class E amplifier using inductive coupling via a designed resonance frequency of 1 MHz. Other frequencies can be used, such as the popular near-field communication (NFC) frequency of 13.66 MHz. Signals are transmitted back via load modulation at frequencies a fraction of the power carrier frequency, thus allowing for extraction of the signal frequency. Results clearly show that modulation frequency tracks closely with open circuit potential, and the system features good sensitivity and linearity. This system holds promise for a host of applications.