# Hypersentized Metamaterials Based on a Corona-Shaped Resonator for Efficient Detection of Glucose
###### Abstract  
In this work, a new design for a real-time noninvasive metamaterial sensor, based on a corona-shaped resonator, is proposed. The sensor was designed numerically and fabricated experimentally in order to be utilized for efficient detection of glucose in aqueous solutions such as water and blood. The sensor was inspired by a corona in-plane-shaped design with the presumption that its circular structure might produce a broader interaction of the electromagnetic waves with the glucose samples. A clear shift in the resonance frequency was observed for various glucose samples, which implies that the proposed sensor has a good sensitivity and can be easily utilized to distinguish any glucose concentration, even though their dielectric coefficients are close. Results showed a superior performance in terms of resonance frequency shift (1.51 GHz) and quality factor (246) compared to those reported in the literature. The transmission variation level \(\Delta|\)S\({}_{21}|\) was investigated for glucose concentration in both water and blood. The sensing mechanism was elaborated through the surface current, electric field and magnetic field distributions on the corona resonator. The proposed metamaterials sensor is considered to be a promising candidate for biosensor and medicine applications in human glycaemia monitoring. c 20  
showed that continuous detection of glucose was possible by using an (LC) inductor-capacitor tank resonator [21]. An open-ended spiral resonator was also presented [22]. This resonator is basically a spiral-shaped microstrip transmission line and has two ports. This study focused on a glucose tolerance test and tracked the transmission coefficient parameter (S21). [PERSON] et al. designed a patch resonator operating in the 2.45 GHz (ISM) industrial, scientific and medical band [23]. In that study, the input impedance of the resonator was tracked at the operating frequency to quantify the blood glucose change, which was approximately 0.04%. Consequently, three different frequencies were proposed [24] to test water and glucose solutions in the range from 0% to 10% and to track the change in glucose solutions by the Q factor. A ring resonator sensor proposed in [25] was used to calibrate the sensor for temperature changes in the sensing environment. An interface test system was proposed for both glucose and vitamins as well as other sugars present in the blood. Another resonator was designed by combining a spiral inductor and interdigital capacitor [26]. When blood plasma was placed on the resonator, the resonance frequency was shifted up if the glucose level was increased in the blood plasma. As such, a sensitivity of 199 MHz per mg/mL was reported in the study. Some other designed antennas have also been proposed by scientists for glucose quantification. For instance, [PERSON] and [PERSON] proposed an antenna through which reflection coefficient S\({}_{11}\) parameters are monitored in order to detect glucose in the operating frequencies of 1 GHz and 6 GHz [27]. Patch antennas operating at 2.45 GHz and 5.8 GHz were proposed in [28], in which deionized water and glucose solutions were analyzed. Results showed that the change was nonlinear and the antenna operating at a higher frequency was more responsive to the change in glucose levels. Another study proposed in [29] showed that using a pig blood digital phantom, the predicted shifts can range between 200 MHz to 300 MHz according to different volumes. A serpentine-shaped antenna with passive coupling was proposed in [30] to monitor the change in S11 response. This study showed that the designed antenna had a narrow bandwidth in air, while the bandwidth was increased to 2.6 GHz for simulation when a finger was used. When a glucose phantom was used, 32 MHz resonance frequency shifts were observed in the concentration range from 0 mg/dL to 200 mg/dL. Since glucose content and the dielectric constant are directly correlated, a metamaterial sensor must satisfy the quality factor (Q) requirements for sensitivity reasons [31; 32; 33].