A Sensitive Glucose Sensor Based on Active Metamaterial With Programmable States

Abstract

This paper provides an active metamaterial (MTM) glucose sensor with programmable functionalities to sensitively detect a large scale of glucose solution concentration up to 7000 mg/dL. The active sensor consists of periodical units that can be individually actuated by PIN diodes via Micro-Control-Unit for obtaining four tunable states presented as digital coding sequences 00/01/10/11. Hence, for the MTM with ${n}$ units, it possesses as many as $4^{n}$ programable resonances, which can be taken advantage of to enhance the sensitivity and expand the detecting range of concentration. Specifically, by investigating different programmable modes for different concentration ranges, it can obtain high sensitivity of 10−3-10−2 dB/(mg/dL) for detecting concentration up to 7000 mg/dL: for concentration of 0–200 mg/dL, the programmable state 1111 is utilized with obtaining the sensitivity of $3.243\times 10^{-3}{-}1.839\times 10^{-2}$ dB/(mg/dL); for concentration of 200–3000 mg/dL, the programmable state 1011 is selected to realize the sensitivity of $2.116\times 10^{-3}{-}1.124\times 10^{-2}$ dB/(mg/dL); for more higher concentration of 3000–7000 mg/dL, another programmable state 0010 is used for obtaining sensitivity of $2.611\times 10^{-4}{-}1.149\times 10^{-3}$ dB/(mg/dL). Particularly, the programmable state 0000 is chosen as the sensing map, so that the measured S11 magnitude in the mapping state can tell the glucose concentration range of the material under test and guide the active MTM sensor go to the appropriate programmable state. This work aims to study the advantage of active sensor with programmable functionalities and motivate the use of sensors with programmable modes to identify, classify, and characterize biochemical and chemical analytes.