A Fully Flexible Handheld Wireless Estrogen Sensing Device

A ultra-lightweight, portable sensing system was developed as a means to detect the amounts of estradiol (E2) in a solution of 0.1 M phosphate buffer. This was done by screen printing a 3-electrode sensor made from a silver/ silver chloride counter electrode, silver reference electrode, and carbon/ ordered mesoporous carbon/ graphite working electrode. This sensor was connected to a custom developed data acquisition circuit, consisting of the LMP91000, a low-power analog front end (AFE) potentiostat paired with the ESP32 microprocessor from Espressif. This circuit was equipped with a USB connection for the purpose of data acquisition and programming, as well as a OLED digital display and a Bluetooth connectivity to display data wirelessly. This apparatus was found to detect estrogen successfully in the range of 5 nM through 5 uM with a slope error of 0.000946 and an R
²
value of 0.9901 utilizing cyclic voltammetry.