Urea detection by ZnO-MWCNT nanocomposite sensor

Xiao

Front. Bioeng. Biotechnol.

et al. 2022

The H2S concentration in exhaled breath increases marginally with the progress of periodontal disease, and H2S is considered to be one of the most important gases related to meat and seafood decomposition; however, the concentration of H2S is low and difficult to detect in such scenarios. In this study, Au–PrFeO3 nanocrystalline powders with high specific surface areas and porosities were prepared using an electrospinning method. Our experimental results show that loading Au on the material provides an effective way to increase its gas sensitivity. Au doping can decrease the material’s resistance by adjusting its energy band, allowing more oxygen ions to be adsorbed onto the material’s surface due to a spillover effect. Compared with pure PrFeO3, the response of 3 wt% Au–PrFeO3 is improved by more than 10 times, and the response time is more than 10 s shorter. In addition, the concentration of H2S due to the decomposition of shrimp was detected using the designed gas sensor, where the error was less than 15%, compared with that obtained using a GC-MS method. This study fully demonstrates the potential of Au–PrFeO3 for H2S concentration detection.

Section: Resultsmentioning

confidence: 99%

Au modified PrFeO3 with hollow tubular structure can be efficient sensing material for H2S detection

Xiao

Front. Bioeng. Biotechnol.

et al. 2022

“…Later, as a result of their analysis to evaluate its electrochemical performance, they showed that glucose biosensor has a broad linear range (0.1–9 mM), high sensitivity (2701 μA mM −1 cm −2 ), and fast response time (< 2.5 s) [ 141 ]. Barthwal and Singh [ 142 ] designed a ZnO/MWCNTs nanocomposite biosensor to detect urea in their study. They indicated that the ZnO/MWCNTs-based sensor has the highest detection characteristics compared to the ZnO and MWCNTs-based sensor.…”

Section: Carbon Nanotubes-based Biosensorsmentioning

confidence: 99%

“…They indicated that the ZnO/MWCNTs-based sensor has the highest detection characteristics compared to the ZnO and MWCNTs-based sensor. Also, they emphasized that the nanocomposite's sensitivity containing 2% MWCNTs is less than 10 s, and the detection limit is 10 ppm [ 142 ]. In the same year, Guan et al successfully developed a CNTs-based hybrid nanocomposite as an electrochemical biosensor for simultaneous high-sensitivity detection of DA and UA.…”

Section: Carbon Nanotubes-based Biosensorsmentioning

confidence: 99%

An Overview on Recent Progress of Metal Oxide/Graphene/CNTs-Based Nanobiosensors

et al. 2021

Nanobiosensors are convenient, practical, and sensitive analyzers that detect chemical and biological agents and convert the results into meaningful data between a biologically active molecule and a recognition element immobilized on the surface of the signal transducer by a physicochemical detector. Due to their fast, accurate and reliable operating characteristics, nanobiosensors are widely used in clinical and nonclinical applications, bedside testing, medical textile industry, environmental monitoring, food safety, etc. They play an important role in such critical applications. Therefore, the design of the biosensing interface is essential in determining the performance of the nanobiosensor. The unique chemical and physical properties of nanomaterials have paved the way for new and improved sensing devices in biosensors. The growing demand for devices with improved sensing and selectivity capability, short response time, lower limit of detection, and low cost causes novel investigations on nanobiomaterials to be used as biosensor scaffolds. Among all other nanomaterials, studies on developing nanobiosensors based on metal oxide nanostructures, graphene and its derivatives, carbon nanotubes, and the widespread use of these nanomaterials as a hybrid structure have recently attracted attention. Nanohybrid structures created by combining these nanostructures will directly meet the future biosensors’ needs with their high electrocatalytic activities. This review addressed the recent developments on these nanomaterials and their derivatives, and their use as biosensor scaffolds. We reviewed these popular nanomaterials by evaluating them with comparative studies, tables, and charts.

Biotech and App Biochem

“…ZnO‐multiwalled carbon nanotube (MWCNT) nanocomposite was prepared by sol–gel technique and used to fabricate potentiometric urea sensor. The developed sensor reveals the sensing response for the concentration range of 0–200 ppm by varying temperatures of 0–300°C 70 …”

Section: Development Of Urea Biosensor Based On Immobilization Matrixmentioning

confidence: 99%

“…ZnO-multiwalled carbon nanotube (MWCNT) nanocomposite was prepared by sol-gel technique and used to fabricate potentiometric urea sensor. The developed sensor reveals the sensing response for the concentration range of 0-200 ppm by varying temperatures of 0-300 • C. 70 A novel screen-printed electrode containing a nonplasticized poly (n-butyl acrylate) (PnBA) membrane entrapped with a hydrogen ionophore was modified with fullereneimmobilized enzyme Urs (C60-Urs) bioconjugate. Fabricated potentiometric urea biosensor shows the sensitivity of 59.67 ± 0.91 mV/decade in the range from 2.31 × 10 −3 to 8.28 × 10 −5 M at pH (7.0).…”

Section: Urea Biosensors Based On the Nanoparticles-carbon Materials ...mentioning

confidence: 99%

Urea biosensors: A comprehensive review

Botewad

Gaikwad²,

Girhe

et al. 2021

Present study is specially designed for the recent advances in biosensors to detect and quantify urea concentration. Urea (carbamide) is an organic compound made up of the carbonyl (C=O) functional group with two −NH2 groups having chemical formula CO (NH2)2. In nature, urea is found everywhere as the result of various processes, and in the human body, urea is an end product of nitrogen metabolism. An excessive concentration of urea in the human body is responsible for different critical diseases such as indigestion, acidity, ulcers, cancer, malfunctioning of kidneys, renal failure, urinary tract obstruction, dehydration, shock, burns, gastrointestinal bleeding, and so on. Moreover, below the normal level may cause hepatic failure, nephritic syndrome, cachexia, and so on. As well as in various fields such as fishery, dairy, food preservation, agriculture, and so on, urea is normally found and its detection is necessary. In urea biosensors, enzyme urease (Urs) is used as a bioreceptor element and retains its long last activity is the critical issue in front of the researcher. During recent decades, different nanoparticles (zinc oxide, nickel oxide, iron oxide, titanium dioxide, tin(IV) oxide, etc.), conducting polymer (polyaniline, polypyrrole, etc.), conducting polymer–nanoparticles composites, carbon materials (carbon nanotubes, graphene oxide, reduced graphene oxide graphene), and so on are used in urea biosensors. The main emphasis of the present study is to provide cumulative and comprehensive information about the sensing parameters of urea biosensors based on the materials used for enzyme immobilization. Besides this special task, this review provides a fruitful discussion on the basics of biosensors briefly for new and upcoming researchers. Thus, the present study may act as a gift for a large audience that come from different fields and are working in biosensors research.