A Low-Cost Disposable Chemical Sensing Platform Based on Discrete Components

A method of fabricating low-cost chemical sensing platforms is presented. The device utilizes a discrete metal-oxide-semiconductor field-effect transistor to detect ionic concentrations in electrolytes, with particular emphasis to pH. Measured results indicate a chemical sensitivity of 36.5 mV/pH, while the device exhibits low-leakage currents (in picoamperes) and a drift of 9 mV/h. The proposed technique has a great potential for disposable implementations, while the sensing selectivity of the device can be easily altered, resulting into a versatile platform.