NH3 Plasma-Treated Magnesium Doped Zinc Oxide in Biomedical Sensors with Electrolyte–Insulator–Semiconductor (EIS) Structure for Urea and Glucose Applications

Electrolyte-insulator-semiconductor (EIS) field-effect sensors belong to a new generation of electronic chips for biochemical sensing, enabling a direct electronic readout. The review gives an overview on recent advances and current trends in the research and development of chemical sensors and biosensors based on the capacitive field-effect EIS structure—the simplest field-effect device, which represents a biochemically sensitive capacitor. Fundamental concepts, physicochemical phenomena underlying the transduction mechanism and application of capacitive EIS sensors for the detection of pH, ion concentrations, and enzymatic reactions, as well as the label-free detection of charged molecules (nucleic acids, proteins, and polyelectrolytes) and nanoparticles, are presented and discussed.

Section: Enzyme-modified Eis Biosensorsmentioning

confidence: 99%

Capacitive Field-Effect EIS Chemical Sensors and Biosensors: A Status Report

Poghossian¹,

Schöning

2020

“…However, Mg ions can easily form because Mg has a low electronegativity (X = 1.31). Zn ions were substituted for Mg ions through the doping process, likely modifying the Zn-O bonds and increasing the surface density [ 71 ]. Several groups reported using EIS-based ZnO thin films as sensors to detect pH in various ranges, as shown in Table 3 .…”

Section: Resultsmentioning

confidence: 99%

“…As a result, trinsic ions could neutralize the dangling bonds and compensate for the defects l underneath the insulator membrane for performance improvement [74]. The highe rate might be due to the high number of crystal defects [71]. Drift is defined as the gradual change in the response of the sensors over time, while the pH value remains constant.…”

Section: The Undoped Zno and Mg-doped Zno Nanorod Sensing Performancementioning

confidence: 99%

Highly Sensitive Magnesium-Doped ZnO Nanorod pH Sensors Based on Electrolyte–Insulator–Semiconductor (EIS) Sensors

Al-Khalqi

Hamid

Al-Hardan

et al. 2021

For highly sensitive pH sensing, an electrolyte insulator semiconductor (EIS) device, based on ZnO nanorod-sensing membrane layers doped with magnesium, was proposed. ZnO nanorod samples prepared via a hydrothermal process with different Mg molar ratios (0–5%) were characterized to explore the impact of magnesium content on the structural and optical characteristics and sensing performance by X-ray diffraction analysis (XRD), atomic force microscopy (AFM), and photoluminescence (PL). The results indicated that the ZnO nanorods doped with 3% Mg had a high hydrogen ion sensitivity (83.77 mV/pH), linearity (96.06%), hysteresis (3 mV), and drift (0.218 mV/h) due to the improved crystalline quality and the surface hydroxyl group role of ZnO. In addition, the detection characteristics varied with the doping concentration and were suitable for developing biomedical detection applications with different detection elements.

“…At the same time, the results achieved with EISCAPs are fully transferable to other EG-FEDs, thereby circumventing the need for fabrication of complicated transistor structures. At present, a lot of single EISCAP sensors modified with particular recognition elements have been developed and successfully proved for the detection of pH [16], concentration of ions [17], enzyme-substrate reactions [18][19][20][21], charged biomolecules (nucleic acids, proteins, biomarkers, nanoparticle/molecule hybrids) [22][23][24][25][26][27][28][29], plant virus particles [30], as well as for realizing biomolecular logic gates [31][32][33]. For recent progress in research and development of chemical sensors and biosensors based on EISCAPs, see [15].…”

Section: Introductionmentioning

confidence: 99%

An Array of On-Chip Integrated, Individually Addressable Capacitive Field-Effect Sensors with Control Gate: Design and Modelling

Poghossian¹,

Welden

Buniatyan

et al. 2021

The on-chip integration of multiple biochemical sensors based on field-effect electrolyte-insulator-semiconductor capacitors (EISCAP) is challenging due to technological difficulties in realization of electrically isolated EISCAPs on the same Si chip. In this work, we present a new simple design for an array of on-chip integrated, individually electrically addressable EISCAPs with an additional control gate (CG-EISCAP). The existence of the CG enables an addressable activation or deactivation of on-chip integrated individual CG-EISCAPs by simple electrical switching the CG of each sensor in various setups, and makes the new design capable for multianalyte detection without cross-talk effects between the sensors in the array. The new designed CG-EISCAP chip was modelled in so-called floating/short-circuited and floating/capacitively-coupled setups, and the corresponding electrical equivalent circuits were developed. In addition, the capacitance-voltage curves of the CG-EISCAP chip in different setups were simulated and compared with that of a single EISCAP sensor. Moreover, the sensitivity of the CG-EISCAP chip to surface potential changes induced by biochemical reactions was simulated and an impact of different parameters, such as gate voltage, insulator thickness and doping concentration in Si, on the sensitivity has been discussed.