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Electrochemical biosensors have been widely used as advanced methods for virus detection. Ongoing efforts are being made to improve their performance by investigating novel materials as electrode modifiers. In this regard, two‐dimensional (2D) materials, such as graphene, transition metal dichalcogenides (TMDs), and transition metal carbides/nitrides (MXenes), have been extensively explored due to their exceptional structural and electrical properties for electrochemical biosensors. This review investigates and summarizes the recently developed 2D materials employed in virus detection. Various strategies to enhance the critical properties of 2D materials, including conductivity, surface area, active sites, selectivity, and wettability, on electrochemical biosensing platforms, which impact their performance, are discussed. Different types of 2D materials (pristine, derivatives, and composites) are described and subsequently evaluated regarding their applications in electrochemical biosensing. This review serves as a valuable guide for designing next‐generation, high‐performance electrochemical biosensors based on 2D materials. [ABSTRACT FROM AUTHOR]

This study reports on the modification of surface plasmon resonance (SPR) chips with molybdenum disulfide–molybdenum trioxide (MoS2–MoO3) microflowers to detect the tuberculosis (TB) markers of CFP-10. The MoS2–MoO3 microflowers were prepared by hydrothermal methods with variations in the pH and amount of trisodium citrate (Na3Ct), which were projected to influence the shape and size of microflower particles. The analysis shows that optimum MoS2–MoO3 hybrid microflowers were obtained at neutral pH using 0.5 g Na3Ct. The modified SPR biosensor exhibits a ten times higher response than the bare Au. Moreover, increasing MoS2–MoO3 thickness results in a higher detection response, sensitivity, and a smaller limit of detection (LOD). Using the optimized material composition, the Au/MoS2–MoO3-integrated SPR sensor can demonstrate sensitivity and LOD of 1.005 and 3.45 ng mL−1, respectively. This biosensor also has good selectivity, stability, and reproducibility based on cross-sensitivity characterization with other analytes and repeated measurements on several chips with different storing times and fabrication batch. Therefore, this proposed SPR biosensor possesses high potential to be further developed and applied as a detection technology for CFP-10 in monitoring and diagnosing TB. [ABSTRACT FROM AUTHOR]

In this study, magnetite (Fe3O4) was composited with graphene (Gr) and used as a non-enzymatic glucose sensor material based of surface plasmon resonance (SPR). The Fe3O4 nanoparticles were succesfully synthesized by ultrasonic co-precipitation method while variation composition of composite samples was successfully prepared at room temperature by varying the concentration ratio of graphene and Fe3O4. The resulting composites have good crystallinity and purity with Fe3O4 nanoparticles attach on the graphene surface. The commercial gold (Au) chip with a thickness of 50 nm was modified with a composite by depositing the various compositions of the composite on the Au chip surface using a spin coater. The most optimal SPR response was shown by the Fe3O4-Gr (3:1) sample with a shift in resonance intensity of 18.2 r.u in detecting 5 mM of glucose. Moreover, the detection limit of the synthesized sensor reaches 0.1995 mM and has good stability at 20 measurement cycles. [ABSTRACT FROM AUTHOR]

A significant amount of pollutants is produced from factories and motor vehicles in the form of gas. Their negative impact on the environment is well known; therefore detection with effective gas sensors is important as part of pollution prevention efforts. Gas sensors use a metal oxide semiconductor, specifically SnO2 nanostructures. This semiconductor is interesting and worthy of further investigation because of its many uses, for example, as lithium battery electrode, energy storage, catalyst, and transistor, and has potential as a gas sensor. In addition, there has to be a discussion of the use of SnO2 as a pollutant gas sensor especially for waste products such as CO, CO2, SO2, and NOx. In this paper, the development of the fabrication of SnO2 nanostructures synthesis will be described as it relates to the performances as pollutant gas sensors. In addition, the functionalization of SnO2 as a gas sensor is extensively discussed with respect to the theory of gas adsorption, the surface features of SnO2, the band gap theory, and electron transfer. [ABSTRACT FROM AUTHOR]

This study reports on the modification of surface plasmon resonance (SPR) chips with molybdenum disulfide-molybdenum trioxide (MoS 2 -MoO 3 ) microflowers to detect the tuberculosis (TB) markers of CFP-10. The MoS 2 -MoO 3 microflowers were prepared by hydrothermal methods with variations in the pH and amount of trisodium citrate (Na 3 Ct), which were projected to influence the shape and size of microflower particles. The analysis shows that optimum MoS 2 -MoO 3 hybrid microflowers were obtained at neutral pH using 0.5 g Na 3 Ct. The modified SPR biosensor exhibits a ten times higher response than the bare Au. Moreover, increasing MoS 2 -MoO 3 thickness results in a higher detection response, sensitivity, and a smaller limit of detection (LOD). Using the optimized material composition, the Au/MoS 2 -MoO 3 -integrated SPR sensor can demonstrate sensitivity and LOD of 1.005 and 3.45 ng mL -1 , respectively. This biosensor also has good selectivity, stability, and reproducibility based on cross-sensitivity characterization with other analytes and repeated measurements on several chips with different storing times and fabrication batch. Therefore, this proposed SPR biosensor possesses high potential to be further developed and applied as a detection technology for CFP-10 in monitoring and diagnosing TB.