In this study we developed a low cost sensor for measuring the concentration of hydrogen peroxide (H₂O₂) in liquids utilizing a spectrometric method. The sensor was tested using various concentrations of a peroxidase enzyme immobilized on a glass substrate. H₂O₂ can be catalyzed by peroxidase and converted into water and oxygen. The reagent 4-amino-phenazone takes up oxygen together with phenol...

A spectroscopic trace gas sensor using a distributed feedback diode laser at λ=1.53 μm and based on quartz enhanced photoacoustic spectroscopy technique is described. The sensor is capable of quasi-simultaneous quantification of trace ammonia, hydrogen cyanide, and acetylene (NH3, HCN, and C2H2, respectively) concentrations at ~100 ppbv levels with a 4s integration time. The sensor design, resp...

In the present work, nanostructures of zeolitic imidazolate frameworks (ZIF-8 and ZIF-67) were combined to obtain a novel chemoresistive sensor, improving the sensitivity of ZIF-67 and facilitating measurement of ZIF-8 by decreasing the resistivity. The sensor detected concentrations as low as 10 ppm of hydrogen increasing its resistivity about 4.5 times. The response of the sensor was compared...

Sterilization of packages prior to product filling is a key step in aseptic filling machines. Chemical sterilization is one of the main conventional techniques in many packaging industries. To monitor the effect of sterilization on test microorganisms (Bacillus atrophaeus spores), an impedimetric sensor approach was developed based on a planar interdigitated electrode (IDE) design. In this work...

We report the application of palladium nanoparticles and thin films for hydrogen sensor. Electrochemically grown palladium particles with spherical shapes deposited on Si substrate and sputter deposited Pd thin films were used to detect hydrogen at room temperature. Grain size dependence of H(2) sensing behavior has been discussed for both types of Pd films. The electrochemically grown Pd nanop...

We developed a hydrogen sensor of reduced graphene oxide-loaded ZnO nanofibers. An extremely high response of about 866 at a low concentration of 100 ppb was obtained. The combined effect of the presence of rGO nanosheets and hydrogen-induced metallization of ZnO played a crucial role in enhancing the detection behavior.

In this paper, a visible light excitable ESIPT probe was developed, which was found to be a very promising colorimetric and fluorescent sensor for rapid and selective detection of hydrogen sulfide in aqueous solution. The sensing mechanism and the application of this probe for hydrogen sulfide detection in biological serum and in simulated wastewater samples were investigated.

A methacrylic-acrylic polymer was synthesised for use as a non-plasticised membrane for hydrogen ion-selective sensor incorporating tridodecylamine as an ionophore. The copolymer consisted of methyl methacrylate and n-butyl acrylate monomers in a ratio of 2:8. Characterisation of the copolymer using FTNMR demonstrated that the amount of each monomer incorporated during solution polymerisation w...

This paper describes the detection principle of a hydrogen peroxide sensor based on the electrolyte metal oxide semiconductor field effect transistor (MOSFET) and possibilities of using different types of redox materials as the gate material for the sensor with respect to the sensitivity and detection limit. After discussing the fundamentals of hydrogen peroxide detection and a short descriptio...

The synthesis parameters and results of investigation of gas sensing properties of tin oxide nanoparticles produced by spark ablation are presented. The nanoparticles have sizes below 30 nm and their specific surface area is about 40 m2/g. In order to study the gas sensing properties, a special structure comprising heater, barrier layers and contact pads was utilized. The resistance of the sens...