A Highly Sensitive Non-Enzymatic Urea Sensor Based on Ni(OH)₂/Mn₃O₄/rGO/PANi Nanocomposites Using Screen-Printed Electrodes

Abstract

Herein, we have developed a highly sensitive non-enzymatic biosensor for the detection of the urea using nickel-manganese oxo/hydroxo metal nanoparticles on reduced graphene oxide, and these nanocomposites were made using the hydrothermal reduction method. Then, the characteristics of these nanocomposites were examined using Fourier transform infrared spectroscopy (FT-IR spectroscopy), energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), inductive coupled plasma (ICP), XRD surface mapping, X-ray Diffraction (XRD) and transmission electron microscopy (TEM). Next, a working electrode modification process was conducted via the electro-polymerization of nanocomposites with aniline on the surface of a screen-printed electrode. We realized that reduction and blocking of all graphene oxide functional groups is important in increasing of sensitivity and prevent protonation of aniline by graphene. Finally, the sensitivity of the modified electrode to urea was evaluated by the cyclic voltammetry method. The results indicate that the sensor works within an acceptable linear range 30 μM to 3.3 mM, (R2 = 0.995, n = 3). Highly sensitivity and the limit of detection are roughly 5139.2 μA mM−1 cm−2 and 16.3 μM, respectively. The sensor demonstrated impressive stability and significant anti-interference properties. Based on these features, it can be concluded that the fabricated sensor is reliable for the non-enzymatic detection of urea.

Advanced Urea Precursors Driven NiCo2O4 Nanostructures Based Non-Enzymatic Urea Sensor for Milk and Urine Real Sample Applications

“…A regression coefficient of 0.99 indicates the NiCo 2 O 4 nanomaterial could play a role in the quantification of urea from practical samples. In Table 1 [ 36 , 37 , 38 , 39 , 40 , 41 ], the proposed non-enzymatic urea sensor configuration is found to perform better than or as well as many of the recently published urea sensors/biosensors in terms of wide linear range, especially for the non-enzymatic urea sensors. The LOD of the presented is also superior to many of the reported works’ enzymatic and non-enzymatic sensors, as given in Table 1 .…”

A Review of Electroactive Nanomaterials in the Detection of Nitrogen-Containing Organic Compounds and Future Applications

“…The obtained Ni(OH) 2 /Mn 3 O 4 /rGO/PANi nanocomposites were used to modify the screen-printed electrodes for the highly sensitive enzyme-less detection of urea. These studies demonstrated that the prepared nanocomposite has the potential to decrease GO functionalities to enhance sensitivity and inhibit the protonation of aniline via graphene structure [68]. Two-dimensional free-standing NiO nanosheets were synthesized using GO paper as a sacrificial template in another study.…”

Electrochemical non-enzymatic urea sensing using polyvinylpyrrolidine derived highly electrocatalytic NiCo2O4 nanowires

“…In addition, Table 3 compares the electrochemical urea sensor with recently reported nonenzymatic urea sensors. As shown in Table 3, the proposed urea configuration is associated with a wide linear range, a limited detection limit, and simple and scalable synthesis of sensing material [71][72][73][74][75]. Consequently, the presented non-enzymatic urea sensor can be used for detecting urea in a variety of real-life samples as an alternative and efficient method.…”