Gold‐Iron Bimetallic Nanoparticles Impregnated Reduced Graphene Oxide Based Nanosensor for Label‐free Detection of Biomarker Related to Non‐alcoholic Fatty Liver Disease

We report for the first time a microwave assisted, one pot, direct, and facile synthesis of monodispersed iron‐gold bimetallic nanoparticles (BNP_Au‐Fe) using glucose as a reducing agent in merely 90 s. The as such synthesized BNP_Au‐Fe were thoroughly characterized using UV‐Vis, XRD, TEM, EDX, elemental mapping, and raman spectroscopy. These BNP_Au‐Fe were further impregnated with reduced graphene oxide (rGO) and coated onto glassy carbon electrode (GCE) to develop a sensor probe for label free electrochemical detection of acetaminophen, which is considered to be a most potent biomarker related to non‐alcoholic fatty liver disease. The sensor probe was systematically characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The BNP_Au‐Fe‐rGO nanocomposite matrix showed the sensing of acetaminophen with a wide dynamic range between 50 and 800 nM with detection limit (DL) of 0.14 nM (±0.05) nM (RSD<4.12 %) that was lower compared to previously reported acetaminophen sensors. To show the practical application of the sensor probe, acetaminophen was detected in human urine samples, which showed the percentage recovery between 86.65 % and 91.32 %. To the best of our knowledge, this is the first report where BNP_Au‐Fe impregnated rGO was used to detect acetaminophen. Interferences due to various molecules such as glucose, serum albumin, glycine, glutamic acid, alanine, citric acid, and ascorbic acid were tested individually and in mixed sample. Long‐term stability of sensor probe was examined which was found to be stable up to 12 weeks. The sensor fabricated using BNP_Au‐Fe‐rGO nanocomposite has many attractive features such as; simplicity, rapidity, and label free detection, hence it could be a method of choice for acetaminophen detection in clinical settings.     

Synthesis of Ferrosoferric Oxide‐graphene Oxide Nanocomposite by Isoelectric Point Method for the Detection of Catechol

Ferrosoferric oxide functionalized graphene oxide nanocomposite with layer by layer structure was synthesized by isoelectric point method in this work. The prepared material was characterized by Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, transmission electron microscopy and Raman spectroscopy. Then the material was used to modify a glassy carbon electrode to fabricate an electrochemical sensor for the detection of catechol. The electrochemical sensor exhibited excellent electrochemical performance towards the detection of catechol with a linear response in the range of 5–205 μM and a detection limit of 2.32 μM. Furthermore, the electrochemical sensor showed excellent selectivity, stability and repeatability. These results revealed ferrosoferric oxide functionalized graphene oxide nanocomposite has potential applications in the fabrication of electrochemical sensors.     

Electrochemical Sensor Based on a Novel Pt−Au Bimetallic Nanoclusters Decorated on Reduced Graphene Oxide for Sensitive Detection of Ofloxacin

Pt−Au nanoclusters decorated on the surface of reduced graphene oxide (rGO/Pt−Au) was facilely prepared by one‐pot electrochemical reduction. The morphology and composition of rGO/Pt−Au composites had been characterized by scanning electron microscopy (SEM) coupled with energy‐dispersive X‐ray spectrometry (EDX), fourier transform‐infrared spectroscopy (FT‐IR) and electrochemical methods. Ofloxacin is a member of synthetic quinolones which has been widely used for the treatment of common diseases in humans and animals. The performance of the rGO/Pt−Au nanocomposite toward the oxidation of ofloxacin was compared with the other similar nanostructures like rGO/Pt and rGO/Au. In the optimized conditions, two linear calibration curves were obtained, from 0.08 to 10 μM and 10 to 100 μM ofloxacin. A detection limit of 0.05 μM ofloxacin was observed at pH 5.7 for the GCE/rGO/Pt−Au. The proposed sensor was successfully applied to determine ofloxacin in tablets and human urine samples and the results were satisfactory.     

Electrochemical Sensor for Sensitive Determination of Capsaicin Using Pd Decorated Reduced Graphene Oxide

In this work, the reduced graphene oxide functionalized with poly dimethyl diallyl ammonium chloride (PDDA) modified palladium nanoparticles (PDDA‐rGO/Pd) had been facile synthesized and used as the sensing layer for sensitive determination of capsaicin. The prepared composite was characterized by transmission electron microscopy, UV‐visible absorption spectroscopy. The image demonstrated that Pd nanoparticles were uniformly distributed on the graphene surface. The electrochemical properties of the prepared sensor were investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The results showed that the nanocomposite exhibits attractive electrocatalytic activity towards the oxidation of capsaicin. This attributed to the synergistic action of the excellent properties of Pd nanoparticles and graphene nanosheets. Under optimized conditions, the electrochemical sensor possessed a dynamic linear range from 0.32 μM to 64 μM with a detection limit of 0.10 μM (S/N=3) for capsaicin detection. Moreover, the cost‐effective and simple fabrication procedure, good reproducibility and stability as well as acceptable accuracy for capsaicin determination in actual samples are also the main advantages of this method, which might have broad application in other amide alkaloid detection.     

Highly Sensitive Electrochemical Hydrogen Peroxide Sensor Based on Iron Oxide‐Reduced Graphene Oxide‐Chitosan Modified with DNA‐Celestine Blue

The present study describes a novel and very sensitive electrochemical assay for determination of hydrogen peroxide (H₂O₂) based on synergistic effects of reduced graphene oxide‐ magnetic iron oxide nanocomposite (rGO‐Fe₃O₄) and celestine blue (CB) for electrochemical reduction of H₂O₂. rGO‐Fe₃O₄ nanocomposite was synthesized and characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X‐ray diffraction (XRD), electrochemical impedance spectroscopy and cyclic voltammetry. Chitosan (Chit) was used for immobilization of amino‐terminated single‐stranded DNA (ss‐DNA) molecules via a glutaraldehyde (GA) to the surface of rGO‐Fe₃O₄. The MTT (3‐(4,5‐Dim ethylt hiazol‐2‐yl)‐2,5‐diphenylt etrazolium bromide) results confirmed the biocompatibility of nanocomposite. Experimental parameters affecting the ss‐DNA molecules immobilization were optimized. Finally, by accumulation of the CB on the surface of the rGO‐Fe₃O₄‐Chit/ssDNA, very sensitive amperometric H₂O₂ sensor was fabricated. The electrocatalytic activity of the rGO‐Fe₃O₄‐Chit/DNA‐CB electrode toward H₂O₂ reduction was found to be very efficient, yielding very low detection limit (DL) of 42 nM and a sensitivity of 8.51 μA/μM. Result shows that complex matrices of the human serum samples did not interfere with the fabricated sensor. The developed sensor provided significant advantages in terms of low detection limit, high stability and good reproducibility for detection of H₂O₂ in comparison with recently reported electrochemical H₂O₂ sensors.     

Synthesis and Electrochemical Investigation of Tetra Amino Cobalt (II) Phthalocyanine Functionalized Polyaniline Nanofiber for the Selective Detection of Dopamine

A new electrochemical sensing platform based on tetra‐amino cobalt (II) phthalocyanine (TACoPc) ingrained polyaniline (PANI) nanofiber composite (TACoPc/PANI hybrid) has been developed for the selective detection of dopamine. The uniform fibrous network of PANI/TACoPc hybrid was synthesized by a one‐step oxidative polymerization at room temperature. The synthesized nanocomposite was characterized using field emission scanning electron microscopy (FESEM), energy dispersive X‐ray (EDX), fourier transmission infrared spectroscopy (FTIR), raman spectroscopy, X‐ray diffraction (XRD) and UV‐Visible spectroscopy. The electrochemical behavior of the TACoPc/PANI hybrid material was studied by using different electrochemical techniques, including cyclic voltammetry (CV) and chronoamperometry in 0.1 M phosphate buffer solution (PBS) of pH 7 by modifying the glassy carbon electrode (GCE). Due to the synergistic impact of PANI and TACoPc, the suggested altered electrode provided superior catalytic performance for dopamine even in the presence of ascorbic acid. It exhibited a linear reaction with a high sensitivity of 1.212 μA/μM cm^?2 and a low detection limit of 0.064 μM over the 20–200 μM concentration range in 0.1 M PBS. One of the commonly faced problems of interference of ascorbic acid and uric acid in the electrochemical detection of dopamine was completely excluded from this modified electrode which led to an increase in the catalytic activity of the material for the detection of dopamine in the presence of ascorbic acid.     

Electrochemical and Photoelectrochemical Sensing of Dihydronicotinamide Adenine Dinucleotide and Glucose Based on Noncovalently Functionalized Reduced Graphene Oxide‐Cadmium Sulfide Quantum Dots/Poly‐Nile Blue Nanocomposite

Reduced graphene oxide‐CdS quantum dots (rGO‐CdS QDs) nanocomposite was synthesized with a one‐pot and facile solvothermal strategy and characterized with X‐ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscopy. The nanocomposite modified with electropolymerized Nile blue (NB) had high electrocatalytic and photoelectrocatalytic activity toward NADH oxidation with lowering 700 mV of overvoltage compared to bare GCE. The linear response up to 200 µM was obtained for photoamperometric determination of NADH and the detection limit was 1 µM (S/N=3). Furthermore, with covalence immobilizing of glucose dehydrogenase onto the nanocomposite, the electrochemical and photoelectrochemical ability of the proposed system toward glucose biosensing was also investigated.     

Electrochemical Detection of Artemisinin Using Cobalt Sulphide/Reduced Graphene Oxide Nanocomposite

Solvothermally synthesized cobalt sulphide/reduced graphene oxide (CoS/rGO) was used to fabricate an electrochemical sensor for detection of artemisinin. Microscopic techniques were used to characterize CoS/rGO nanocomposite. The electrochemical sensor was fabricated by modifying the surface of glassy carbon electrode with CoS/rGO nanocomposite. [Fe(CN)6]^3−/4− was used as a mediator to aid oxidation of artemisinin. Differential pulse voltammetric technique was used for the detection of artemisinin. A linear range of 30–100 μM was used. Experimentally, a detection limit of 0.5 μM was obtained. Therefore, the developed sensor can be used for quality control of artemisinin.     

Silver nanoparticles-decorated reduced graphene oxide: A novel peroxidase-like activity nanomaterial for development of a colorimetric glucose biosensor

In this study, we present a novel approach to prepare of a colorimetric chemical sensor for H₂O₂ and a glucose biosensor basing on the use of peroxidase-like activity of silver nanoparticles decorated on reduced graphene oxide sheets (AgNPs@rGO) nanocomposite. Herein, AgNPs@rGO nanocomposite was synthesized by a one-step hydrothermal reducing method and its physico-chemical properties were characterized by X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), Ultraviolet–visible spectroscopy (UV–Vis), Fourier-Transform Infrared spectroscopy (FT-IR) and Energy Dispersive X-ray spectroscopy (EDX). Obtained evaluation results shown that the synthesized AgNPs/rGO nanocomposite has performed an efficient peroxidase-like activity for the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB_red) by H₂O₂, leading to the oxidized form (TMB_ox) which presents a typical blue color (maximum of absorbance at λ_max = 655 nm). A colorimetric assay for H₂O₂ detection was designed and fabricated with a limit of detection of 20 μM. Moreover, we have used of AgNPs/rGO nanocomposite combining with glucose oxidase (GOx) to develop of a colorimetric glucose biosensor with a low limit of detection of 40 μM and a linear dynamic range from 125 μM to 1 mM. This glucose test was applied to the detection of glucose in human serum samples.     

Cobalt nanoparticles anchored to porous silicon as a novel modifier for the construction of enzyme‐free hydrogen peroxide screen‐printed sensor

In this work, a screen‐printed carbon electrode (SPCE) was modified with a cobalt/porous silicon (Co@PSi) nanocomposite powder to develop a nonenzymatic sensor for the detection of hydrogen peroxide. The Co@PSi nanocomposite was synthesized through the chemical reaction between silicon powder in a HF/HNO₃ solution and cobalt cations. In this process, cobalt nanoparticles were anchored on the porous silicon. The structure and morphology of the synthesized nanocomposite were investigated by X‐ray diffraction, Fourier transform infrared spectroscopy, X‐ray photoemission spectroscopy, energy dispersive X‐ray spectroscopy, and field‐emission scanning electron microscopy. The constructed nonenzymatic, screen‐printed sensors based on the Co@PSi nanocomposite showed perfect electrocatalytic oxidation response to hydrogen peroxide over the range 1–170 and 170–3,770 μmol/L with the limit of detection of 0.8 μmol/L. In addition, the Co@PSi‐SPCE sensor exhibited good selectivity for the determination of H₂O₂ in the presence of common interfering species including glucose, ascorbic acid, uric acid, dopamine, nitrate, and nitrite ions. The constructed electrochemical sensor was successfully used for the determination of H₂O₂ in real samples.     

Fabrication of Electrochemical Sensor Based on CeO2−SnO2 Nanocomposite Loaded on Pd Support for Determination of Nitrite at Trace Levels

Here, an electrochemical sensor based on CeO₂‐SnO₂/Pd was prepared and used for highly selective and sensitive determination of nitrite in some real samples. This nanocomposite was characterized by various methods like X‐ray photoelectron spectroscopy, X‐ray diffraction, energy dispersive spectroscopy, Fourier‐transform infrared spectroscopy, field emission scanning electron microscopy, and transmission electron microscopy. The electrochemical behavior of the sensor was evaluated by cyclic voltammetry. The results showed excellent catalytic property of the nanocomposite as a an electrocatalyst for nitrite oxidation. In the following, the experimental parameters affecting the analytical signal for nitrite were optimized. Under the optimal conditions, the limit of detection and sensitivity of the sensor were calculated as 0.10 μM and 652.95 μA.mM^?1.cm^?2, respectively. Also, the response of the sensor was linear in the range of 0.36 to 2200 μM of nitrite. Finally, some of the inherent features of the sensor such as repeatability, reproducibility and stability were examined after evaluation of the sensor selectivity in the presence of several interfering species.     

Magnetite Nanorods Stabilized by Polyaniline/Reduced Graphene Oxide as a Sensing Platform for Selective and Sensitive Non‐enzymatic Hydrogen Peroxide Detection

In this study, magnetite nanorods stabilized on polyaniline/reduced graphene oxide (Fe₃O₄@PANI/rGO) was synthesized via a wet‐reflux strategy. The possible formation of Fe₃O₄@PANI/rGO was morphologically and structurally verified by field emission scanning electron microscopy (FE‐SEM), Fourier transform infrared (FT‐IR) spectroscopy, Raman spectroscopy, X‐ray diffraction (XRD) and X‐ray photoelectron spectroscopy (XPS). Furthermore, the thermal stability of Fe₃O₄@PANI/rGO was measured by a thermogravimetric analyzer (TGA); the composite had good thermal stability owing to the ceramic nature of Fe₃O₄. The Fe₃O₄@PANI/rGO has been applied as a potential sensing platform for electrochemical detection of hydrogen peroxide (H₂O₂). By the combined efforts of extended active surface area, active carbon support, more catalytic active sites and high electrical conductivity, the Fe₃O₄@PANI/rGO exhibited an improved performance toward the non‐enzymatic detection of H₂O₂ in 0.5 M KOH with a fast response time (5 s), high sensitivity (223.7 μA mM^?1 cm^?2), low limit of detection (4.45 μM) and wide linear range (100 μM–1.5 mM). Furthermore, the fabricated sensor exhibited excellent recovery rates (94.2–104.0 %) during real sample analysis.     

Nickel and Tungsten Bimetallic Nanoparticles Modified Pencil Graphite Electrode: A High-performance Electrochemical Sensor for Detection of Endocrine Disruptor Bisphenol A

In this work, an economically viable, very low cost, indigenous, ubiquitously available electrochemical sensor based on bimetallic nickel and tungsten nanoparticles modified pencil graphite electrode (NiNP-WNP@PGE) was fabricated for the sensitive and selective detection of bisphenol A (BPA). The NiNP-WNP@PGE sensor was prepared by a facile electrochemical one step co-deposition method. The prepared nanocomposite was morphologically characterized by scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD), electrochemically by cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The proposed sensor displayed high electrocatalytic activity towards electro-oxidation of BPA with one irreversible peak. The fabricated sensor displayed a wide detection window between 0.025 μM and 250 μM with a limit of detection of 0.012 μM. PGE sensor was successfully engaged for the detection of BPA in bottled water, biological, and baby glass samples.     

Synthesis of Cysteine Modified MoS2 Nanocomposite: A Biocompatible Electrochemical Sensor Material and its Application to the Determination of Antidiabetic Dapagliflozin

Herein, for the first time, a new generation cysteine modified MoS₂ (Cys@MoS₂) based electrochemical sensor was reported. The electrochemical behaviour of dapagliflozin (DAP) was investigated through differential pulse voltammetry (DPV) on the developed sensor (Cys@MoS₂/GCE). The transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FTIR), x‐ray diffraction spectroscopy (XRD) and x‐ray photoelectron spectroscopy (XPS) methods were performed for structural and morphological characterizations of Cys@MoS₂ nanocomposite. On the surface of Cys@MoS₂/GCE, an irreversible anodic peak was observed at 1324 mV. Under the optimal conditions, linear calibration curve with two working ranges between 2.0–60.0 μM and 60.0–110.0 μM were obtained and limit of detection was found to be 1.6 μM. The developed sensor was successfully applied to determine the content of DAP in pharmaceutical sample with satisfying recovery results. It is concluded that Cys@MoS₂/GCE is a reliable, easy to apply and cost‐effective sensor for the routine DAP analysis in pharmaceutical samples.     

A novel nitrite sensor based on graphene/polypyrrole/chitosan nanocomposite modified glassy carbon electrode

A novel nitrite sensor was fabricated based on a graphene/polypyrrole/chitosan nanocomposite film modified glassy carbon electrode. The nanocomposite film was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy and Raman spectroscopy. The electron transfer behaviour of the modified electrodes was investigated in [Fe(CN)(6)](3-)/(4-) redox probe using cyclic voltammetry and electrochemical impedance spectroscopy. Differential pulse voltammetry and amperometry were used to study the electrochemical properties of the proposed sensor. Under optimum conditions, the sensor exhibited good reproducibility and stability for nitrite determination. Linear response was obtained in the range of 0.5-722 μM with a detection limit of 0.1 μM (S/N = 3) for nitrite determination.     

Functionalization of Reduced Graphene Oxide with β‐cyclodextrin Modified Palladium Nanoparticles for the Detection of Hydrazine in Environmental Water Samples

A sensitive and selective hydrazine sensor was developed by β‐cyclodextrin modified palladium nanoparticles decorated reduced graphene oxide (PdNPs‐β‐CD/rGO) nanocomposite. The PdNPs‐β‐CD/rGO hybrid material was prepared by simple electrochemical method. The hydrophobic cavity of β‐CD ineracts with palladium nanoparticles by hydrophobic interaction and further it is uniformly assembled on the rGO surface through hydrogen bond formation, which is clearly confirmed by FT‐IR, FESEM and TEM. The high electrocatalytic activity of hydrazine oxidation was observed at −0.05 V (vs. Ag/AgCl) on PdNPs‐β‐CD/rGO modified electrode; due to the excellent stabilization, high catalytic activity and large surface area of the PdNPs‐β‐CD/rGO composite. The PdNPs‐β‐CD/rGO fabricated hydrazine sensor exhibited an excellent analytical performance, including high sensitivity (1.95 μA μM⁻¹ cm⁻²), lower detection limit (28 nM) and a wide linear range (0.05 to 1600 μM). We also demonstrated that the PdNPs‐β‐CD/rGO nanocomposite modified electrode is a highly selective and sensitive sensor towards detection of hydrazine among the various interfering species. Hence, the proposed hydrazine sensor is able to determine hydrazine in different water samples.     

A Novel Enzymatic Glucose Biosensor and Nonenzymatic Hydrogen Peroxide Sensor Based on (3‐Aminopropyl) Triethoxysilane Functionalized Reduced Graphene Oxide

In the present study, a novel enzymatic glucose biosensor using glucose oxidase (GOx) immobilized into (3‐aminopropyl) triethoxysilane (APTES) functionalized reduced graphene oxide (rGO‐APTES) and hydrogen peroxide sensor based on rGO‐APTES modified glassy carbon (GC) electrode were fabricated. Nafion (Nf) was used as a protective membrane. For the characterization of the composites, Fourier transform infrared spectroscopy (FTIR), X‐ray powder diffractometer (XRD), and transmission electron microscopy (TEM) were used. The electrochemical properties of the modified electrodes were investigated using electrochemical impedance spectroscopy, cyclic voltammetry, and amperometry. The resulting Nf/rGO‐APTES/GOx/GC and Nf/rGO‐APTES/GC composites showed good electrocatalytical activity toward glucose and H₂O₂, respectively. The Nf/rGO‐APTES/GC electrode exhibited a linear range of H₂O₂ concentration from 0.05 to 15.25 mM with a detection limit (LOD) of 0.017 mM and sensitivity of 124.87 μA mM⁻¹ cm⁻². The Nf/rGO‐APTES/GOx/GC electrode showed a linear range of glucose from 0.02 to 4.340 mM with a LOD of 9 μM and sensitivity of 75.26 μA mM⁻¹ cm⁻². Also, the sensor and biosensor had notable selectivity, repeatability, reproducibility, and storage stability.     

Electrochemical Detection of 2-Nitrophenol Using a Glassy Carbon Electrode Modified with BaO Nanorods

Here, an electrochemical detection approach (differential pulse voltammetry) was employed to develop a 2-nitrophenol (2-NP) sensor probe using a glassy carbon electrode (GCE) coated by wet-chemically synthesized nanorods (NRs) of BaO. The prepared BaO NRs were characterized by field-emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS) and powder X-ray diffraction (XRD) analysis. The peak currents by differential pulse voltammetric (DPV) analysis of 2-NP are plotted against the concentration to obtain the calibration curve of the 2-NP detection. It was found to be linear from 1.5 to 9.0 μM, defined as the dynamic range (LDR) for 2-NP detection in phosphate buffer solution. The sensor sensitivity was calculated from the slope of LDR by considering the active surface area of NRs coated on GCE (0.0316 cm²) and found as 17.6 μAμM⁻¹ cm⁻². The limit of detection (LOD) was calculated as 0.50±0.025 μM from the signal/noise (S/N) ratio of 3. Moreover, the sensor analytical parameters such as reproducibility, long-term performing ability (stability), response time and validity in real environmental samples were found acceptable and to give satisfactory results. The development of a nanomaterial-based electrochemical chemical sensor might be an effective approach to sensor technology to detect carcinogenic and hazardous toxins for environmental safety and healthcare fields in a broad scale.     

Designing and fabrication of a novel gold nanocomposite structure: application in electrochemical sensing of bisphenol A

In this article, a highly sensitive electrochemical sensor is introduced for direct electro-oxidation of bisphenol A (BPA). The novel nanocomposite was prepared based on multi-walled carbon nanotube/thiol functionalised magnetic nanoparticles (Fe₃O₄-SH) as an immobilisation platform and gold nanoparticles (AuNPs) as an amplifying electrochemical signal. The chemisorbed AuNPs exhibited excellent electrochemical activity for the detection of BPA. Some analysing techniques such as Fourier transform infrared spectroscopy, field emission scanning electron microscopy, transmission electron microscopy and energy-dispersive x-ray diffraction exposed the formation of nanocomposite. Under optimum conditions (pH 9), the sensor showed a linear range between 0.002–240 μM, with high sensitivity (0.25 μA μM^?1) along with low detection limit (6.73 × 10^?10 M). Moreover, nanocomposites could efficiently decrease the effect of interfering agents and remarkably enhance the utility of sensor at detection of BPA in some real samples.     

A Sensitive and Selective Nitrite Detection in Water Using Graphene/Platinum Nanocomposite

A glassy carbon electrode modified with reduced graphene oxide and platinum nanocomposite film was developed simply by electrochemical method for the sensitive and selective detection of nitrite in water. The electrochemical reduction of graphene oxide (GO) efficiently eliminates oxygen‐containing functional groups. Pt nanoparticles were electrochemically and homogeneously deposited on the ErGO surface. Field emission scanning electron microscopy (FE‐SEM), Raman spectroscopy, attenuated total reflectance‐fourier transform infrared spectroscopy (ATR‐FTIR), electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV) were used to examine the surface morphology and electrocatalytic properties of the Pt‐ErGO nanocomposite film‐modified electrode surface. The fabricated nitrite sensor showed good electrochemical performance with two linear ranges; one from 5 to 100 µM (R²=0.9995) and the other from 100 to 1000 µM (R²=0.9972) and a detection limit of 0.22 µM. The proposed sensor was successfully applied for the detection of nitrite in tap water samples which proves performance of the Pt‐ErGO nanocomposite films.